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The subject matter has been discussed for years and all diesel enthusiasts/owners know how important it is to maintain proper levels of fuel pressure via the "transfer pump" or Lift Pump for reliable operation. There are many requirements that each owner/operator may wish to achieve in replacing the OE Carter or perhaps making an aftermarket selection. Notably, most have  had the rude awakening of a failed VP44 following the failure of the Lift Pump in a too late scenario. The cost of a VP44 compared to the Factory (Carter) Lift Pump is considerable and many of us have learned the hard way.

 

The general consensus among the vast majority is to eliminate the factory OE Carter pump and invest in a robust Class 8 aftermarket system. There are several companies that offer such devices with different performance levels and packaging. Many, come complete with new 1/2" fuel lines, mounting structures, fuel fittings and electrical control harnesses. Some companies offer more modest devices with a budgetary aspect at minimum level. All of this becomes apparent when a conscientious owner/operator begins the research to purchase a new device or system. I for one have stopped reading "Lift Pump" threads because it's so very painful...and I've already seen so many stories of the same old blah blah blah! No, I am not being insensitive to a fellow CTD owner's plight...after all, this is most likely a "new to Diesels" type person. The post is reaching out to the "experienced" diesel enthusiasts for suggestions and perhaps constructive feed-back, prior to making that large investment. Confidence from fellow CTD owners in what they may have purchased or installed goes a long way with the new guy or lady looking for an answer.

 

For just a moment allow me a little latitude...Oh God! Not another Lift Pump story :rolleyes:...Yes but, not what you might think. This will drill-down in a different manor so, please bare with me. :neutral:

 

The factory OE "Carter" is such a little peanut-whistle why did Dodge do this? The fact is, as many know quite well, the decision was Daimler Chrysler who dictated to Cummins to provide the complete CTD engine package as a drop-in module. Carter's specifications states that, "this pump is to be located within 18 inches of the fuel supply"...it's sad to know these details greatly after the fact. This detail was covered 20 years ago on nearly every diesel website worldwide. This led to the unfortunate degradation of the Carter transfer pumps reputation.

 

In actuality, the Carter LP (lift pump) has excellent design characteristics!

 

s-l640.jpg.bce971601899ab61ba1a6c8913871ab5.jpg

    At first glance the appearance seems a bit "puny" but, let's look at some of the "not so apparent features"... First of all, Carter is a very large world-wide company who provide a vast selection of produced articles. They also provide excellent technical documentation regarding the application of their products in numerous industrial devices, automotive, marine and aeronautical systems or platforms. Electro-mechanical pumps of this nature, are just a single product that they produce... In our application, CTD's are at first, supplied copious amounts of diesel fuel at acceptable levels to operate the engine and provide flow-through for critical cooling of the VP44 in return to the fuel tank. This is "how" the designed system was to perform. :rolleyes:

 

We know as experienced CTD owners that this was not always the case. Many of us know the error of mounting this little well designed pump nearly 10 feet forward of the fuel supply (not to specification of Carter Inc.) and ask this little pump to draw fuel through a small 1/4" line and....force the liquid through "banjo-bolt" fittings as delivery to the VP44? Wow...it's an unreasonable expectation for an electro mechanical pump, that most likely, costs less than $20 to produce in the Philippines. :duh: None the less, how many of us have had the occasional chat with a CTD owner (who knows nothing) that tells you they purchased the 2nd Gen new, he has 187K miles and has NEVER replaced the VP44 (he doesn't know what a VP44 is...you just taught him the word) and NO...he has never put a fuel pump into his truck! Yeah ! You know what I'm talking about ! How can this be ? Well...I guess some folks are a lot more lucky than I am... heck...this guy doesn't even know about 2 Stroke for lubricity,... credit our GodFather @Mopar1973Man 

 

 

This photo is well known as a starting point. Also, a depiction of what Cummins had to do to appease Daimler Chrysler's request of a "drop in module" CTD

878-f3.jpg.3ace9c273bb6242ed5e2f8dc00efa60a.jpg

 

Okay...what is "a well designed pump"... even if it is not mounted correctly?

 

At Carter, where they have been doing this longer than any of our familiar after-market LP suppliers... please note:

 

1... A fully enclosed hermetically sealed electro-machanical  device that allows the liquid fuel to act as a cooling medium and fully immerses the active armature of the 12 volt DC motor to never exceed the temperature of the supplied liquid (diesel fuel)...because it is "airless" (hermetically sealed) there is no ignition to cause flammability. It's liquid cooled !

 

2... The entire body or "encapsulation" as hermetic, provides absolute closure or isolation of the motor-brushes as they kiss the surface of the armature in run condition. This is very important as a DC (direct current) motor with carbon pile brushes act as a wild uncontrolled sparking noise source generator !!! 

This is a normal phenomena of any analog DC brushed motor. A given manufacturer of brushed DC motors, depending on purpose, will take steps to "silence" the electrical (RF noise generation)...the term "purpose" needs clarification... "if the motor is a "CCS" continuous commercial service (runs all the time) then, additional electronic filtering or "shunting" of the armature must be provided.

 

3... Carter Inc. employs RF Engineers (BSEE graduates minimum) to accomplish technical requirements when contracted specifications are to be adhered to for final product production. An expensive platform in any industrial production would have a string of engineers along with design engineers specking' components or assemblies that will be encapsulated within the finalized product. This occurred in "our" beloved CTD's with electro mechanical LP's....the Carter is "RF quiet" for continuous run condition. 

 

Let's examine the electronic terminals of the Carter LP

 

1050224.jpg.ae2ca33a3733fb423d14c83563d3032c.jpgNote: The plastic weather-guard assembly directly attached to the full metal housing that contains the + & - 12 volt DC !

4... This connection point provides the direct current to power this LP. I wish you to fully understand what you're looking at. As viewed you'll note "both Plus+ and -minus" is provided at this connection point. You must also NOTE, the + and - are arriving directly from a single "pair" connection of both + & - .... I know you'll think I'm stating things "twice" and I want you to know this is an attempt to be a "balanced" feed. The housing of the pump is fully DC grounded when it is attached to the mounting bracket. In a "balanced" feed the "minus" or "negative" is NOT directly at chassis ground...it is merely + and - of the source (12 volts DC in our case) the body of the pump IS directly grounded but, the "source" is isolated from the pump body. Put your Ohm meter on either terminal and touch the pump body....there is NO direct DC continuity in a "balanced" source. This is a sexy way of making things very "quiet" electronically. Professional audio studios are fully balanced systems using "Cannon" connectors with three terminals. One is "plus" Two is "minus" and Three is "shield ground"....hence, balanced and NO Hum or Static noise. (Hey...those guys at Carter make a quiet pump...it's wimpy but, damn quiet)

 

Okay...now let us examine what is going on internally on the back side of the connection point.

 

430880121_CTD007.jpg.b56089c2cb56672d7d6675e5b696c778.jpg

    A careful surgery, with hack-saw in hand, to remove the hermetically sealed body cover and expose the multi-octave filter or "shunting" design of this Carter LP. The double sided epoxy circuit board with modern surface-mount chip capacitors is excellent. This board is located directly at the input of the 12 volt source with virtually zero component lead length (surface mount) to provide shunting of the make and break contact that the brushes are doing directly at the armature when in "run" condition. This DC motor is virtually by-passed or shunted for any RF noise or "spiking" all the way passed 450 MHz!  NOTE ! I did say "spiking" or should I say... "ripple"... this is a source of nasty "ripple" directly connected to the entire 12 volt DC rail of our beloved CTD's

Quality engineering of analog DC motors remove such garbage before it is introduced to devices such as aircraft, fighter jets, military assault platforms, nuclear submarines and civilian automobiles.

 

There are many preferred after market suppliers of fuel pumps or systems available and many are quite note worthy when it applies to providing solid reliable fuel flow.

 

maxresdefault.jpg.26252839fca770e5a09305c22d942fa4.jpgMany of these platforms exceed the requirements in "fuel flow" for the average diesel enthusiast. Sometimes choices are made because the owner has future plans of building enhanced performance characteristics. Some choose additional GPM for the insurance of added cooling by the "return flow" system design. All of the after market manufacturers of the upper end platforms do this with ease and price the devices accordingly.

 

Caution in selecting any device that may cause unknown after effects in any mobile platform. The CTD 2nd Gen, is something I've looked at carefully for many years and I've made concerted efforts to correct some electrical over sites for the betterment of these noble platforms. I too have made large investments and the after market LP selections are not cheap. I was exceptionally disturbed when I successfully installed an after market LP system. The extreme effort to correctly and cleanly install the system along with all the cool JIC fittings and complete the project with pride that someone may examine my work was all accomplished. Then I shortly discovered the absolute short comings of my nearly $900 investment. I blamed myself for not test operating the device on a test bench and viewing the horrendous RF interference HASH that took out everything from 500 KHz (just below the commercial broadcast band) to well above 500 MHz.

 

Is this important to you?... It is and perhaps it has not become apparent by the way such broadband RF interference manifests itself within a closed stand alone 12 volt system. To make these statements to you, the reader, let me be clear, I use and own a Hewlett Packard 8921A Digital RF test device, at $24,000.00 ...one must be "a fully certifiable crazy idiot" to have this along with a Tektronix  200 MHz 4 channel scope...and someone asked..."Do you need such instruments to look at $25.00 DC motors"...no but, I'm fully confident in my findings.:wink:

 

Let's take a look at the much enhanced DC motor of an after market LP...it is irrelevant as to the manufacturer...they are all the same.a864e95f.jpg.da7040b1197f92ae0a81860f58fc7ea5.jpg

This is an initial basic disassembly procedure that needs to be performed. It's very easy to accomplish.

 

f3c533a1.jpg.39e49e1d946308efe60dbd41f3285f31.jpg

Once you have the cookie opened you'll be able to view the end-plate where the carbon brushes reside in their respective holders. Many of these devices and earlier models vary by design in physical form but, they are all the same in regard to an end-plate with brush tube holders.

 

Here is the end-plate removed from a different LP unit and we can see the very minimal by-pass engineering of a single .47 Mfd mylar capacitor directly across the two brushes. Note, the lead length.

IMAG0110.jpg.69efc37b93118642e6debfbf8810fa02.jpg

     This is typical of an inexpensive analog DC motor...I'll estimate the average wholesale cost of this to be somewhere around $10 to $15 US dollars. It would vary greatly, according to quantity buying levels. The only capacitor seen here is barley a by-pass or shunt...I'd prefer to call this a carbon brush protector. As the armature spins in normal operation, the "make" and "break" of the brushes riding against the armature where "flame" occurs...this cap is merely removing or dampening the "spark" and aiding brush-life longevity. At .47 Mfd it's really only helping at the lowest frequencies to roll off the RF spiking, also with long leads, transversing the distance between the two brushes does not help with the higher frequencies of this wild free-running spark-gap transmitter. This is a far cry from the excellent by-passing techniques incorporated into the wimpy little Carter device. :cry:

 

Let us take a look at the fix procedure to begin " RF silencing" one of these very substantial LP platforms. We can't be as effective as the fully closed hermetically sealed package but, with careful effort you can knock this "ripple hash" down by 40db or better in just this simple step.

 

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The procedure above depicts a simple "drill and tap" technique using small machine thread hardware. 6/32 or 10/32 should suffice. You can use what ever hardware is available in your junk box as long as it is small enough to fit into the limited working space. Purchasing a small tap and companion drill at your local hardware store to match your "screw-thread pitch" is very low in cost. The skill required to do this is modest, just take your time and carefully hand-cut your threads gently. The cast aluminum end-caps are very easy to drill and tap. NO 9% IPA's should be consumed prior to drilling! Keep your hole straight :stuned: and pay attention to the "depth" of your drill. With the armature removed you can "eye-in" an approximate location for the mounting hole to accommodate the miniature "lug"...this is where you make an accurate decision of the "angle" for the lug's contact arm to avoid contact with a spinning armature in "run-mode". You must also consider component "lead length"...keep this EXTREMELY short...it will be like working on a Swiss watch in confined space.

NOTE: You must loctite your threads! This procedure is introducing component count within a very critical area...errors in loose components will be catastrophic !!! You will make NO errors here! :smart:

 

Sorry...my photo is fuzzy. The photo below is zoomed-out for examination of component placement within the end-cap structure. It is tight but, it is precise and highly efficient.

This depicts component selection: two each .1 Mfd silver Mica 100 volt dipped packages. I happened to have these in my junk box and standard miniature ceramic caps would also suffice.

1859163608_CTD003-CopyAa2.jpg.fc3237a507c140a1e68d30062ba2ce8a.jpg

This completes the "critical" internal modification to initially "RF silence" the armature brush contact event point.

 

1118445152_CTD004a3.jpg.0a2dfb40fe014dd9ce900ea0b1bf8e93.jpg

I buy electronic components/parts from DigiKey or Mouser...these two capacitors will set you back about 30 cents each...your shipping cost will be ten bucks! Boy...I miss those cheesy little Radio Shacks. It was so convenient to buy little things like this for little money within my own community. Times have certainly changed. :(

Now, carefully reassemble your enhanced LP device and mount it into it's operational nest on the vehicle.

 

The photo below is the final step in this procedure. Again, this shunt capacitor is a .1 Mfd Orange drop package rated at 100 volts. I do prefer this package  over standard Ceramic disks under the hood within engine compartments due to heat stress. These maintain tolerance over an extremely wide temperature range.

 2012578118_IMG_0243aa4.jpg.6b29cb8d446c12296eb3b0209a211fe3.jpg

The shortest leads possible, again, is the goal...the lead is directly connected to the relay socket where the 12 volts DC is connected through the relay contacts, that when "closed", provides DC excitation to the LP. I could have made these leads shorter but, I utilized the present ground on the firewall for convenience.

 

Insert the relay back into the socket.

 1892742296_IMG_0240aaa4.jpg.da678cbd50f7e527533adbeacaf023d6.jpg

This now completes the entire procedure. The monetary expenditure amounts to less than $1.00 for the capacitors. The time involved is substantial.

 

The $689.00 plus dollar, advanced LP platforms available should have arrived fully prepared for trouble free installation and operation. The design engineering staff at Dailmer Chrysler would have never introduced an uncontrolled CCS constant run DC motor device into their platforms at any level. Cummins also, would have never allowed a DC pump without qualification standards to be specified for any production platform. The factory OE Lift Pump from Carter is a very under powered volumetric unit and their is no debating that short coming however: electronically it's design is superior in every aspect. The entire hermetically sealed housing acts as a complete Faraday Shield to fully encapsulate all electromagnetic static fields of force. It is a "dead silent" RF void device!

 

 

This is just an example...all of the after market companies tout their prowess in delivering liquid fuel at astounding levels of performance, be it a stock engine or perhaps an extremely high horse powered competition street killing monster. None of them provide a civilized RF silenced DC motor to prevent "other" electronic automotive control elements from being harmed when operated within the confined structure of the vehicle. Note: not one bit of verbiage regarding the actual DC motor that powers the device! But, it pumps fluid like heck!

airdog_I_edit4.11-1.jpg.4176478014f6fc37731f8354c5b3dc01.jpg 

 

 I so dearly appreciate the flow factors, the filter systems, the mounting structures and comprehensive packages to alleviate all the short comings of my dismal factory transfer pump issues. Knowing well, that I'll never allow my one thousand dollar plus VP44 from ever being fuel starved again, by selecting an aftermarket LP system...only to realize afterwards, that the introduction of this major investment into my vehicle is now causing electronic issues, else where, within the vehicle!

 

The expensive sound systems, vehicle speed sensing systems, erratic operation of TC lock-unlock, cruse control abnormalities, and radio communications equipment. All of these things at one time operated without error, you enjoyed the accurate trouble free aspects of your prized motor vehicle, then...something happened!

 

Being cautious about adding any electronic implement into a trusted vehicle is always prudent. Asking the right questions before hand is always best practice. This information applies to ALL Vehicles regardless of manufacturer Ford, Chevy or Dodge.

 

This article is following additional postings on this web-site...Mike Nelson @Mopar1973Man and Nick @Me78569are struggling to keep this small and independent site operational. I am not affiliated with any supplier or manufacturer...I am a contributing customer who appreciates the time proven and solid information/guidance these two men  provide to the diesel community.

 

I humbly share this knowledge with the CTD fraternity with enthusiasm, for the improvement of our platforms...may I ask a very small favor...if you find the information on this site of value could you please consider making a one dollar donation to the site to keep the lights on :pray:  

 

Thank you, Respectfully,

W-T 

 

 

 

 

 

 

 

Edited by W-T
photo in wrong location

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  • @Rotax3006Thank you Sir, I am a fellow Montanan, originally from Butte, and I share this kind of information for the CTD enthusiasts who diligently search for answers. I receive personal satisfaction

  • I would have to read some more to see if me and the heard have been personally insulted or not. I will have my machine call you rmachine at a later date.

  • @Dieselfuture...I believe your effort in looking at this subject matter will reveal positive results. I would never create projects just to make "busy work" for my fellow CTD enthusiasts.   

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Welcome back. I hope things are better for you now out that way. Though what I read sounds like it will be a while before anything is even close to normal. 

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@dripley thank you Sir, yes, this situation is very long term...the clean up is commencing between rain however; it will be years before this area is even close to being normal again. I'm also limited with internet...I'm using my iPhone HotSpot to be able to participate here.

Cheers

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I found the iron ring that came out of an old computer charging system. Could I use that as a simpler way to reduce AC noise from the lift pump? I think you told me that one could wrap the iron ring with quality wire (sort of like a winding), grounding it to the frame and run the lift pump harness through it. Also ground the lift pump housing. Would this be a alternative, not as good of course, but perhaps somewhat effective?

      Thank you in advance.

Thank you for article. 

 My airdog lift pump is mounted closest to fuel tank as possible.  Pump is mounted next to where the pick up bed meets truck cab.  Reason is was told these pump designs “push” fuel better than “suck” fuel.  But unknown if that is a proven fact or not.  

At the resent time, my wire relay connection is mounted on the firewall.  I could shorten the wire run approx. 8 1/2 feet by extending the relay connection closer to the lift pump. The new wire run from the DC pump to the "shunt capacitor"  would then be a length of 1 foot to 18 inches,  as opposed to 8 1/2 feet, and not exposed to weather best I can see. Of course it would not be as easy to check fuse, but would be a lot closed to pump motor.  

If I were to extend the relay connection and fuse, the relay connection would be at lot closer to lift pump,  would there be any real benefit?  

Thank you for your insight 

  • Author
4 hours ago, JAG1 said:

I found the iron ring that came out of an old computer charging system. Could I use that as a simpler way to reduce AC noise from the lift pump? I think you told me that one could wrap the iron ring with quality wire (sort of like a winding), grounding it to the frame and run the lift pump harness through it. Also ground the lift pump housing. Would this be a alternative, not as good of course, but perhaps somewhat effective?

      Thank you in advance.

 

Mike @JAG1 excellent incite...the use of a toroid core with multiple winding's to build maximum lumped inductance is an additional way of blocking undesired or extraneous signal on a DC supply line. Many computer monitor manufacturers will have an "egg" on the multi-conductor cable running to the computer mainframe. Much of the high speed switching data on the line can and certainly does radiate undesired digital-hash. Just as an analog DC motor does in run-mode.

 

Here is an example of a home-brew AC line filter constructed around a  2 1/2" toriod core. The properties of the core's "mix" elements (iron,nickle,cadmium) vary and is chosen for the frequencies or band of frequencies targeted for suppression.  

index.jpg.78e598052760fbdbe220a228dfdaf343.jpg  The amount of "windings" present in this example (core value unknown) generally indicates higher frequencies are to be attenuated and the amount of inductance is nominal but, not enough for our needs in suppressing the trash of aftermarket Lift Pumps drawing 5 to 8 Amps of current. Some of the larger aftermarket Lift Pumps may sink as much as 10+ Amps of current and now we're talking about some real power factors.

 

images.jpg.faafb7afb6137bfdc19dd00a675a7dc6.jpgHere we have an improved choke wound with #10 enameled solid copper that would be capable of conducting larger current demands with very little loss because the wire size has less resistance. This is important to us because we want the maximum voltage to be supplied to the DC motor and not dissipated in the form of heat due to the series resistance of the line or wire making up the choke itself.

 

124713100_images2.jpg.50f2e692c417c58ab45e17cf6fd14e2c.jpgHere we have a bulk choke constructed on a larger toroid doughnut with tightly packed turns and NO overlapping. This is approaching "real" levels of inductance to virtually "choke" the heck out of the chicken..... @dripleyis not included here.:lmao2:

 

The goal of a bulk DC choke is to build it as large and  with as many turns as possible to increase Inductance. The larger the inductance the better it is for low to mid range frequencies of suppression interest. 

 

This home-brew choke needs to be packaged to prevent damage and water/snow contamination.

 

This home-brew choke must be located directly at the "noise source" (LP motor input leads) and secured for physical integrity.

 

The use of "Fair-Rite" beads placed onto the DC leads will be of little assistance in our goal of high current DC choking.

 

In a "two wire" run from the power source (plus and minus) you would build chokes for both lines.

 

Yes again @JAG1 Mike...extreme attention to the way a LP mount structure is physically attached to the frame is critical ! The flat surfaces mating together should have NO paint insulating the two flat structures. Put "NoLox" grease between the two surfaces and tighten the mounting bolts to "squish" the grease and protrude outward so as to not allow moisture to collect between the two mating surfaces. Never expect a "bolt" or "screw" to act as a proper ground when you're trying to suppress RF hash. The larger the surfaces are in mating together will provide the best integrity of noise suppression. The noise "is" RF...it does NOT FLOW within a conducting element (wire) it FLOWS on the SURFACE of the conducting element (wire)... it is called SKIN EFFECT... the paint/powder-coating must be removed on ANY MATING SURFACES of a "noise generating" device (DC motor).

 

All the aftermarket Lift Pumps are packaged beautifully. NONE of them have CONTINUITY between their own body elements. During the initial by-passing procedure earlier in this thread I NEGLECTED to highlight a VERY IMPORTANT issue ! @JAG1 has brought this to the forefront. I apologize for this oversight...

 

You must disassemble the entire aftermarket LP unit and clean all mating surfaces to remove ALL ANODIZING and PAINT at EVERY contacting/mating point. NO continuity means NO suppression. I am so very sorry for having left this out of the initial documentation. Please note: the Original Carter LP HAS NO PAINT IN THE ENTIRE CONSTRUCTION of THE DEVICE. 

 

I used a Dremel Tool with small bits to "scarify" every hole where an assembly screw/bolt passes through to join another piece of the modular body construction. The beautiful "Anodized" surfaces of the fluid pump body as it mates to the lower fully "Anodized" water separator and fuel filter housing is FULLY NON-CONDUCTIVE !

 

I'm so very embarrassed to have NOT provided this imperative aspect. Sorry for my major error...there is no way around this...you must completely disassemble the LP platforms to restore full body continuity and then because of the full disassembly procedure, it lends well, to perform the "by-passing" procedure at the motor armature end-cap assembly. :duh:

 

I am just mortified by this omission !

 

@JAG1 Mike...I am sorry... it was my original observation so long ago that drove me into this comprehensive refurbishment of this $700 pain in the A... if I could regain my composure with just a bit of saving grace on my behalf...NOTHING WORTH WHILE IS EASY...this aspect is ONE OF THEM.

 

Indeed, our conversation has come to light in my cluttered mind and I now fully recall my primary reason for this entire thread. MY pump was a pile of junk electronically the day it arrived at my home. It was so bad, I called the manufacturer and spoke directly with the owner of the company. He was a very kind and gracious man. Our conversation continued for 3 hours that day. He openly informed me that his pursuit was into the US Military diesel vehicle contract part procurement program. When the subject matter was fully understood and how the fix would be incorporated into the package the task became daunting. The exchange was professional and enlightening for this gentleman . The aspect of having this product pass the "specification" hurdle for demanding US military standards for electronic compatibility... he then admitted to me that this concept had not been considered.

The next day I was offered employment on the Engineering staff of the company...I was honored however: I did not wish to relocate.

 

Again...I am sorry for dragging all my fellow CTD enthusiasts through the mud...credit goes to @JAG1 for surreptitiously stirring the pot of a failing biological hard drive. :doh: ...in the future I will have my notes compiled prior to annoying everyone. :rolleyes:

 

With humility

W-T

 

 

 

 

  • Author
6 hours ago, 015point9 said:

Thank you for article. 

 

 My airdog lift pump is mounted closest to fuel tank as possible.  Pump is mounted next to where the pick up bed meets truck cab.  Reason is was told these pump designs “push” fuel better than “suck” fuel.  But unknown if that is a proven fact or not.  

At the resent time, my wire relay connection is mounted on the firewall.  I could shorten the wire run approx. 8 1/2 feet by extending the relay connection closer to the lift pump. The new wire run from the DC pump to the "shunt capacitor"  would then be a length of 1 foot to 18 inches,  as opposed to 8 1/2 feet, and not exposed to weather best I can see. Of course it would not be as easy to check fuse, but would be a lot closed to pump motor.  

If I were to extend the relay connection and fuse, the relay connection would be at lot closer to lift pump,  would there be any real benefit?  

Thank you for your insight 

@015point9 ...

 

Your set up mirrors mine almost exactly and you wouldn't benefit in redesigning the present DC supply for the LP. Having the slave DC relay on the firewall is the most favorable location because it's a quasi protected environment and also some convenient serviceability advantages. I like being able to power the relay without the ECU connection to power purge a new filter install and burp all the air from the system. The firewall location allows that rare function when needed with only a couple of jumper-leads equipped with small alligator clips...extracting 12 DC to trigger the slave relay from the PDC is right there in the work area and you can hard run the LP without starting the engine.

 

The shunt cap at the slave relay socket was placed to remove the last bit of RF trash emanating up the DC line from the LP. Observing this on the panoramic spectrum analyzer was a final step I took after fixing the continuity of the entire LP's package and by-passing the armature. Yes, a lot of work to accomplish when the little Carter pump's design required no electrical correction to begin with.

 

Your estimation of DC cable length is very accurate and interesting.

 

The length of 8 and one half feet is notable in this subject. Using a RF constant formula of 468/F in MHz lets look at this

 

468/27.085 MHz (channel 11 citizens band) equals 17.27 feet as a resonant 1/2 wave antenna for 11 meters. Now, divide that in half and we get 8.6 feet or a perfect 1/4 wave resonant length of wire at that frequency. The 1/4 wave directly attached to the wide-band noise generator (aftermarket LP) is now spewing RF trash with a "tuned 1/4 wave" antenna with surprising efficiency.

 

The wide-band trash from these aftermarket LP's extends from just below the commercial Broadcast Band all the way into the UHF spectrum of 500 MHz plus...it is interesting to note that when one unknowingly attaches a convenient length of wire to power up and operate a DC motor of this type, you may very well be enhancing the dirty aspects of these LP's to be even more harmful due to their poorly designed package. So, if you wish... you could use your CB transceiver as a poor man's spectrum analyzer(sniffer) with just a short piece of coax connected to the rig...strip off the other end with a two inch pig-tail and with a length of say 12 feet you could walk around your truck as it is running, turn up your volume and "sniff" around. You can find and hear lot's of things....the problem is "if the aftermarket LP" is already trashing your receiver than you must correct the big trash first. If your CB is quiet and receiving correctly, you start your truck and the noise becomes unbelievable....that same broadband trash is effectively permeating all the electronics in your vehicle.

 

How bad is this? well...if you know it's there... could there be an issue in an emergency such as a faulty operating ABS system, speed sensing system, TC Lock/Unlock, cruise control, ect, ect. Fact is...it wasn't there when the truck arrived new. Introducing an electronic implement into the vehicle changed something. If your CB can't hear when your driving...something is wrong.

 

@JAG1 is onto something to even further quiet these aftermarket LP's...a quality designed high current bulk DC choke mounted directly at the DC input of the offending device is another way of making our CTD's even harder. I must caution all who venture down this path...be comprehensive...no single procedure will correct everything. The largest improvement will be to correct the non-continuity of the entire platform...it doesn't conduct between the individual modular body parts and with extraneous capacitive coupling between elements makes it even worse. Yeah...they look pretty but, these are the trashiest DC motor assemblies I have ever seen for automotive application.

 

Cheers,

W-T 

3 hours ago, W-T said:

.. @dripleyis not included here.:lmao2:

I would have to read some more to see if me and the heard have been personally insulted or not.:think: I will have my machine call you rmachine at a later date.:tongue:

Wondering if this has anything to do with quadzilla Bluetooth connection as its in the same general area where most have their lift pump wireing and relay. 

I'm also wondering if my intermittent abs/brake light has anything to do with it, even though I put brand new Timpken wheel bearings with sensors in, and when scanned with Snap-on it's the left driver side sensor that drops out, possible RF interference? 

This is very interesting, thank you for the write-up. I'll be moving a few things around to see if anything changes.

 

You'll be a good salesman for a fuel boss all mechanical pump, or any good quality mechanical lift pump for that matter :whistle2:

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Thanks for mentioning me giving me much credit W-T, but all I did was ask something about a 'donut dealy bob' that you originally educated me on about a year ago. After that, I began looking for that iron ring to show up somewhere in my shop anytime I was out there. Now that I found it.......is indeed the right size to help choke off that damn loud squawking chicken.

  • Author
2 hours ago, Dieselfuture said:

Wondering if this has anything to do with quadzilla Bluetooth connection as its in the same general area where most have their lift pump wireing and relay. 

I'm also wondering if my intermittent abs/brake light has anything to do with it, even though I put brand new Timpken wheel bearings with sensors in, and when scanned with Snap-on it's the left driver side sensor that drops out, possible RF interference? 

This is very interesting, thank you for the write-up. I'll be moving a few things around to see if anything changes.

 

You'll be a good salesman for a fuel boss all mechanical pump, or any good quality mechanical lift pump for that matter :whistle2:

@Dieselfuture...I believe your effort in looking at this subject matter will reveal positive results. I would never create projects just to make "busy work" for my fellow CTD enthusiasts. 

 

Again, the factory LP was a fine "electrically sound" unit...however; volumetric efficiency and original mounting location with fittings (banjo type) was a poor decision on Daimler Chrysler's behalf.

 

Also...I wish to remain "neutral" in respect to the many companies who produce quality aftermarket electro-mechanical transfer-pumps. The performance aspect of these aftermarket pumps is not being questioned...I'm scrutinizing the lack of built in electronic silencing I expected after shelling out hundreds of dollars to correct one issue and inheriting another problem or side effect.

 

I admit the procedure to clean-up or shall I coin "electronically  blue-print" an analog DC motor is a bit involved but, the results are impressive in silencing the wide-band RF trash.

 

The ONLY DC motor in almost every automobile that is NOT fully silenced to the "point of perfection" is the windshield wiper motor. The fact that the operation is intermittent and used on occasions when required  deems this as less important but, an analog DC motor that runs continuously should not be allowed to emit "wide-band" RF hash to the detriment of the surrounding electrical environment.  

 

I would hope that eventually, the aftermarket manufacturers would correct this issue and clean-up their expensive alternative products. At a production level this is quite easy and affordable to accomplish.

 

I would be interested in your observations and results as you move forward in this matter.  

 

W-T   

I have nothing of value to add but wanted to say that was one hell of a good write up.  My old roommate from college was an EE major and always talked about this stuff.  Way over my head, I just build roads but if anybody wants to talk about super elevations I'm your guy... :thumb1:

15 minutes ago, Rotax3006 said:

I have nothing of value to add but wanted to say that was one hell of a good write up.  My old roommate from college was an EE major and always talked about this stuff.  Way over my head, I just build roads but if anybody wants to talk about super elevations I'm your guy... :thumb1:

I concur.  Super elevations are easier to understand for me also.

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@Rotax3006Thank you Sir, I am a fellow Montanan, originally from Butte, and I share this kind of information for the CTD enthusiasts who diligently search for answers. I receive personal satisfaction knowing I've been able to assist others in matters of electronic issues. This web site has some excellent individuals contributing solid information and I consider it an honor to participate.

 

Cheers :cool:     

44 minutes ago, W-T said:

@Rotax3006Thank you Sir, I am a fellow Montanan, originally from Butte, and I share this kind of information for the CTD enthusiasts who diligently search for answers. I receive personal satisfaction knowing I've been able to assist others in matters of electronic issues. This web site has some excellent individuals contributing solid information and I consider it an honor to participate.

 

Cheers :cool:     

We honored to have you. Many thanks.

  • Owner
1 hour ago, W-T said:

@Rotax3006Thank you Sir, I am a fellow Montanan, originally from Butte, and I share this kind of information for the CTD enthusiasts who diligently search for answers. I receive personal satisfaction knowing I've been able to assist others in matters of electronic issues. This web site has some excellent individuals contributing solid information and I consider it an honor to participate.

 

Cheers :cool:     

 

46 minutes ago, dripley said:

We honored to have you. Many thanks.

 

:iagree::thanks:

  • 4 weeks later...

being in ham radio this is all fact, the "ripples" are called harmonics and any open electrical spar/arc can, does, and will create unwanted RF and the harmonics can go up and down the radio spectrum for ages.... that unwanted rf can be inducted into other resonant circuits and cause problems.

 

its why i have a mechanical lift pump :lol2:

  • Author
16 hours ago, CUMMINSDIESELPWR said:

being in ham radio this is all fact, the "ripples" are called harmonics 

 

 

Specifically "harmonics" are ODD and EVEN multiples of a fundamental frequency of interest. An example would be 27 MHz x 2= 54 MHz or simply the second harmonic of the fundamental. In a practice most EVEN order harmonics are self cancelling in a tuned circuit...the ODD harmonic multiples are removed by the filtering design of the coupled circuit or following tuned circuit. The Q factor will determine the depth of acceptance or REJECT of the unwanted extraneous RF energy in it's inherent design.

 

This thread is specifically referring to the WIDE BAND white noise or HASH being produced by the DC motor armature in a normal run-mode operation. This observation is only pointing out the "non-bypassed" production of common DC motors being utilized to power these gear-driven transfer pumps. 

 

Earlier in the thread I made reference to the "wild uncontrolled SPARK-GAP transmitter" which is the result of any analog brushed DC motor's armature in spinning motion. With little attention or engineering being applied to filter or suppress the results of "wide band hash" across the entire frequency spectrum we can expect to possibly have issues elsewhere in a closed 12 volt automotive electrical system. Again the shining example of correct DC suppression is the Carter Pump that all of us have decided to eliminate from our platforms due to the poor performance characteristics of fluid handling capabilities. 

 

The aspect of "ripple" is customarily a term applied to an extraneous AC waveform being imposed upon a DC rail or a pure DC 12 volt power supply having filter or rectification issues. This is observed in several threads where @Mopar1973Man has enlightened all of us to the health of the 135 Amp Alternators and their demise in clean operation.

 

I appreciate your observation and your choice of a mechanical transfer pump in order to avoid some of the pitfalls we all face when choosing an aftermarket electro-mechanical transfer pump. Perhaps the attention to this unfortunate over site on behalf of the leading manufacturers may lead to an improvement in the near future.

 

With respect,

W-T

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