DTT Assassin not pumping!

[rancherman]

Please refresh  my memory here:   Is  the fuel  that  leaves the vp  (through the  overflow valve)   fuel that  has been  THROUGH the internal vane pump..  which means  the vane pump is boosting the internal pressures..   Or is it fuel that   only subject to the lp pressure?   Meaning,    if the lp  is  supplying enough volume,  then the internal  vane pump  takes it  the rest of the way.  (increases it   enough to pop the  overflow valve)    This  would only work if  there is  enough volume, and all needs  are met.  On the  otherhand,  is the  overflow there to guarantee the internal vane pump is  not subjects to anymore than it's  preset  level?   iirc  14 psi?

[Mopar1973Man]

Overflow valve is the fuel leaving the rotor as far as what I can figure out on the body ports.

[Wild and Free]

I am talking about reliability and durability and simplicity and wonder why aftermarket never jumped on a design of pump that was higher flow that mounts in the same spot and driven off the cam.

[rancherman]

Overflow valve is the fuel leaving the rotor as far as what I can figure out on the body ports.

so,   all fuel entering the  vp  MUSt GO   straight to the  vane pump.. and  what isn't  needed  by the  HP part   is  then  directed to the overflow?

[rancherman]

I am talking about reliability and durability and simplicity and wonder why aftermarket never jumped on a design of pump that was higher flow that mounts in the same spot and driven off the cam.

another thing  i've never  understood is  IF  the  main thing that is  'cooked'  in the  VP is the circuit board,   why  hasn't it ever been relocated?..   Is  the  servo motor that   changes the timing  intregal to this   piece?    Is it  a  moveable   part that  changes  timing,  or is there a  piezioelectric  gizmo  that  does the work?...  

 

Most vp  pump 'failures'  are  electronic,  correct?

[Mopar1973Man]

I am talking about reliability and durability and simplicity and wonder why aftermarket never jumped on a design of pump that was higher flow that mounts in the same spot and driven off the cam.

 

Because on the 1998.5 and forward there is no cam lobe to drive pump. You'd have to change cams.

[Mopar1973Man]

another thing  i've never  understood is  IF  the  main thing that is  'cooked'  in the  VP is the circuit board,   why  hasn't it ever been relocated?..   Is  the  servo motor that   changes the timing  intregal to this   piece?    Is it  a  moveable   part that  changes  timing,  or is there a  piezioelectric  gizmo  that  does the work?...  

 

Most vp  pump 'failures'  are  electronic,  correct?

 

The cooking of the PSG is mostly the alternator noise. I've only found a very small handful of people that actually seen the overheat code on the VP44.

[Yankneck696]

I have looked into relocating the PSG computer with a spare pump. It would be very difficult, to say the least.

 

Ed

[rancherman]

The cooking of the PSG is mostly the alternator noise. I've only found a very small handful of people that actually seen the overheat code on the VP44.

 

 

I have looked into relocating the PSG computer with a spare pump. It would be very difficult, to say the least.

 

Ed

   This is exactly what drives me nuts  on  ANY  forum!    Wasn't it  just   a few months ago...   we all sat  behind our computers,  and  watched a thread  unfold before our very eyes  on   the  exact  transistor that    burns out?   Theories on   why it burns out..   etc. 

  I  took away from that    experience,   was    THAT  little  transistor was  responible  for   a  majority of      pump  'failures'... 

Now,  Mike  throws   the fact out  that   'AC noise'  is  what is  killing the   PSG.     

So,    exactly  what  are we  trying to prevent from  'overheating'   inside the VP  with   multiple   thousands of dollars of aftermarket   fuel pumps  that have a half life  of   a  'fart in a whirlwind' ???

[Wild and Free]

Because on the 1998.5 and forward there is no cam lobe to drive pump. You'd have to change cams.

I know that but as things go there wasn't enough trouble with the old system and they didn't sell enough parts and service so lets see how we can make more money off the masses.........................

[MnTom]

I know that but as things go there wasn't enough trouble with the old system and they didn't sell enough parts and service so lets see how we can make more money off the masses.........................

Exactly. My 12 valve with 289K miles is still on the original lift pump and original injection pump. I have concidered upgrading to a 24 valve, but with all the fueling issues....... My 12 valve keeps looking better and better!

[JAG1]

   This is exactly what drives me nuts  on  ANY  forum!    Wasn't it  just   a few months ago...   we all sat  behind our computers,  and  watched a thread  unfold before our very eyes  on   the  exact  transistor that    burns out?   Theories on   why it burns out..   etc. 

  I  took away from that    experience,   was    THAT  little  transistor was  responible  for   a  majority of      pump  'failures'... 

Now,  Mike  throws   the fact out  that   'AC noise'  is  what is  killing the   PSG.     

So,    exactly  what  are we  trying to prevent from  'overheating'   inside the VP  with   multiple   thousands of dollars of aftermarket   fuel pumps  that have a half life  of   a  'fart in a whirlwind' ???

Way I understand it is there are such tight tolarences (SP.) inside the VP that excessive heat will affect it. Plus I don't know how cheap bean countin' company executives can be that decide to not use silver in the solder like they are supposed to do. So the connections go bad is what I'm hearing.

Yes... and it pisses me off to see people getting wealthy off of doing a disservice to Americans and their families, in reference to not using silver. Some have fought and gave it all.

Bible says to cast your bread upon the water because God knows that incorporating generosity toward others comes back many fold.

Edited January 4, 2015 by JAG1

[rancherman]

well, NEXT time my vp goes south.. it'll be converted over to P pump. Already have an extra one on the shelf. Conversion kits 'on sale' are about 1300.

 

*throwing in towel*

[JAG1]

Robert let me know when your on vacation.... I need one too

[CSM]

Pretty sure the 250GPH versions will supply enough for anything you wanted on a street driven machine. I know the 150's will get you to well over 600 hp easily.

 

I agree with the cam lobe pump idea completely... A cam lobe pump and a small accumulator would have worked just fine.  

 

The modern pumps are 250gph and whatever... Yet, how many PSI is that rated at?  I don't recall seeing that pressure, and as they aren't positive displacement pumps, that gph number is a function of suction head and pressure head.  

 

In a perfect world, the trucks would be setup like a business jets fuel system at work...  Mechanical pump at the engine pushing fuel back to a motive flow jet pump in the tank (no moving parts!) which pushes fuel to the engine.  There is also a boost pump in the tank used for initial starts, "stuff," and emergencies that supplies fuel to the engine and jet pump. However, trucks are expensive enough.  

[rancherman]

I like the idea of  a small accumulator..   for 2 reasons!   

First would be the  smoothing out of the  impulses,  with the added benefit of  a small  reservoir always  'on demand'... and  well,  it'd  be  the perfect  isolator  for the  fp  gauge! 

 

'spose   a    air-over  type   or   would  a  spring/piston type  used  here?    

Edited January 5, 2015 by rancherman

[hex0rz]

....hmmm, at the rate you fella's are going, you'd almost think we ought to come together collectively and do some R&D on it and get someone to start doing the maching work on it! I'm sure someone here has a CAD program for CNC, etc...

[ISX]

Is there any reason twin screw pumps aren't used? I saw one company making them for gassers. Just little 100gph ones but still. They are positive displacement and I would think it would be better. I'm talking the ones that look like superchargers.. I don't like gerotor pumps. They just don't trip my trigger.

[rancherman]

Is there any reason twin screw pumps aren't used? I saw one company making them for gassers. Just little 100gph ones but still. They are positive displacement and I would think it would be better. I'm talking the ones that look like superchargers.. I don't like gerotor pumps. They just don't trip my trigger.

is this what you mean?

Walbro High Pressure Twin Screw Fuel Pump

Walbro High Pressure Twin Screw Fuel Pump

Click image for larger view

Quantity in Basket: none

Part Number: L710020000

List Price: $314.95

Your Price: $289.95

Quantity in stock: 6

Estimated shipping date: Today

Free Shipping:W/$250.00+ Order

Shipping Weight: 3.00 pounds

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The Walbro high pressure twin screw fuel pump can be used as an in-tank fuel pump or external pump & works especially well in high pressure applications. Lingenfelter's fuel pump flow testing results showed flow rates of almost 340 LPH.

Walbro's twin screw design sets a new standard in high-flow fuel pumps with minimal pressure drop-off and heating while operating at high pressures. The twin screw pump is compatible with gas, E15 or diesel.

Inlet: 15 mm barb

Outlet: 8 mm barb

Length: 226 mm

Diameter: 43 mm

Terminals: (-) 5 mm, (+) 4 mm

Old Pierburg / TI part number: 7.00228.510

New TI Walbro part number: 7.00228.51

[ISX]

Yes that.  

 

http://www.lingenfelter.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LPE&Product_Code=L710020000&Category_Code=C75#.VKyrBMZ--1s