Mechanical lift pump

[Welcometmnm]

Probably not a bad idea for a strainer. When I cut into the fuel fill hose, the inside was like it delaminated. 

[IBMobile]

On 6/20/2019 at 11:08 AM, Gregturley said:

Its not a filter its a strainer.

It's like running the fuel through a window screen, keeps the big bugs out but lets the gnats through. 

[Welcometmnm]

We got bigger fish to fryHome 2.m4a

recording of my brand new Cummins lift pump. 

My other two never made this stuttering sound. Well that didn’t work out well. 

The pump sounds like it’s cutting out. 

The electrical connection is inserted till it clicks. 

Truck was run about ten minutes after new lift pump install. 

 

Just got off the phone with glacier diesel  (Richard). Sounds like the fuel is going by the Hobbs switch. All I have to do is increase pressure. Whew! 

Edited June 21, 2019 by Welcometmnm

[Dieselfuture]

5 hours ago, IBMobile said:

It's like running the fuel through a window screen, keeps the big bugs out but lets the gnats through. 

Them things are bad this year, angry. 

[Mopar1973Man]

On 6/20/2019 at 11:56 AM, Welcometmnm said:

Only question I have is I thought Glacier didn’t recommend a pre-filter. Puts to much strain on the unit. 

 

Strange that FASS and AirDog both put pre-filters on and causes no strain on the pump. Is the might mechanical pump that weak because it nearly double the distance from the fuel tank now at the very front bumper? Hmmm... Pumps are not design to suck or pull fuel long distance they are designed to PUSH fuel. This is where the weakness is being the pump must be located at the crank and adding huge distance from the fuel tank and forcing the pump to pull fuel longer distances and add a prefilter would impact the pump performance. Yeah this is basic pumps 101. The suction side of the pump should be as short as possible.

Edited June 23, 2019 by Mopar1973Man

[IBMobile]

The old cars had little diaphragm fuel pumps attached to the side of the engineblock powered by a lever ridding on a camshaft lobe sucking fuel all the way from the tank.  The 12 valve diesel engine had the same set up.  Now a mechanical straight cut gear fuel pump at the front of engine being driven by hundreds of horse power from front crankshaft pully sucks my fuel just fine with no electrical problems of any kind. 

Edited June 23, 2019 by IBMobile

[Gregturley]

It's true most electric pumps are designed to push. Mechanical pumps don't seem to have that weakness as they have been used for decades in push and pull applications with far less problems than electric pumps, with the mechanical pumps flowing more volume in many cases. I crewed on a 2300 hp twin turbo drag car that had 2 massive electric fuel pumps mounted less than 1 foot from the rear of the fuel cell. We had fuel starvation issues when the car launched. We changed to a mechanical belt drive with the pump mounted to the motor plate, fuel cell still in the trunk, and solved all the fuel issues. This car pulled 1.15-1.18 60 foot times consistently after the change.

[Welcometmnm]

Good to know Gregturley, that speaks volumes!  There is plus and minus’s in all decisions. So having a better than stock filter system might be more important to one person. I would have purchased a FASS for that reason seems like a good choice. I personally like the idea of a back up lift pump. 

Some people carried around a spare lift pump. What’s better than carrying around a spare lift than one that’s already tied into the system. Also  I searched high and low for FB failures. In the pump they seem to be nonexistent. Problems have accrued in the bypass valve.  Another consideration that played a factor in my choice of the Fuel Boss mechanical pump was an article done up by a member here. That was the RF factor. Something a guy doesn’t see but can play havoc on this generation Dodge. 

[Gregturley]

From my research there is nothing stopping you from putting almost any filtration system that you want after the FB pump. Right now I'm running a Baldwin PF7977 filter in the stock filter housing. Better than stock 01 filter, not as good as FASS filtration, but easy and  what i can afford. 

[Mopar1973Man]

On 6/23/2019 at 10:35 AM, IBMobile said:

The old cars had little diaphragm fuel pumps attached to the side of the engineblock powered by a lever ridding on a camshaft lobe sucking fuel all the way from the tank.  The 12 valve diesel engine had the same set up.

 

Also had it problems back in the day called vapor locking for gasoline engines and on the 12V engine were known for not able to keep the VE pump supplied only if left stock. Even the 12 P-pump trucks most had to ditch the mechanical pump for a AirDog or FASS because that mechanical pump could keep up on the high RPM's the flow efficiency was way low. 

[Gregturley]

Thats the nice thing about the aftermarket. There's something for everyone if you look hard enough. The hard part is figuring out what you want to spend your money on.

[Mopar1973Man]

Come to think of it there hasn't been a mechanical fuel pump in many years in either gasoline engine or diesel engines. Every one moved the fuel pump to the fuel tank or near the fuel tank. 

[IBMobile]

 

5 hours ago, Mopar1973Man said:

Every one moved the fuel pump to the fuel tank or near the fuel tank. 

One reason the fuel pumps are in or near the fuel tank is not because its pushing the fuel but rather it's pressurizing the fuel in the lines to keep the fuel from boiling and causing vapor lock.   Gasoline, depending on the blend, will start to boil at a temp as low as 104°F (#2 diesel 540°F)  and produce vapor bubbles in the fuel line this will cause engine misfire and stalling.   Also, when the engine is turned off a check valve keeps pressure in the fuel lines; this is called rest pressure.  The rest pressure keeps the fuel from boiling and vapor locking when the car is parked for a short time with a hot engine.  The rest pressure bleeds off at a slow rate as the engine cools.  

 

Another reason for the fuel pump to be in the fuel tank is to keep it cool.   With the pump immures in fuel and cool running the pump does not have to be built as robust as one mounted on the out side of the tank.  The vehicle manufacturer also benefits when the pump mounted with the fuel sender unit making for a quick install and is less expensive than a pump and fuel sender mounted separately.

 

10 hours ago, Mopar1973Man said:

not able to keep the VE pump supplied only if left stock.

This is a design problem that Chrysler inflected on the Cummins engine.  Even the VP44 suffers from this and leads us back to this point... mechanical or electric fuel pump...pull or push.   

 

[wil440]

It will be mechanical for me when I get around to it

[JAG1]

The diaphragm style lift pumps for the 12 valve riding on a cam lobe have reliability problems too. There is a new style attachment point where the diaphragm linkage rod attached to the arm riding on the cam is built cheaper and does not stay attached. I discovered this when comparing the original 1992 lift pump, still operational with 250,000 miles on it was built so much better. Even going to Cummins parts I wasn't able to get the original style lift pump. The newer cheaply built ones kept failing and required a fuel pressure gauge be installed. I loved that old truck for almost 22 yrs.

Edited June 25, 2019 by JAG1

[Mopar1973Man]

On 6/24/2019 at 9:10 PM, IBMobile said:

One reason the fuel pumps are in or near the fuel tank is not because its pushing the fuel but rather it's pressurizing the fuel in the lines to keep the fuel from boiling and causing vapor lock.

 

Correct. When you place a liquid or fuel in a vacuum state then the boiling point goes down even lower. This is why long suction lines for either diesel or gasoline is a bad idea. When a fuel is place into a pressure state then the boiling point rises. Hence why vapor locking no longer happens with gasoline engine at 40 to 60 PSI of injector pressure from the fuel tank to the rail.  Compared to fuel pump on a the side of block and the entire run of the steel line is in mild vacuum state and the boiling point is reduced too low and the vapor locking start early. 

 

Just remember vacuum is what we use to remove water from A/C system because it will cause water to boil at a very low temperature like 70*F. Just like the coolant system a 16 PSI cap help to raise the boiling point of water up above 212*F with coolant it rises even more.

[Gregturley]

Serious question.. Has anyone here ever had vapor lock on a diesel? I'm not talking about "I ran my diesel dry now it wont start" situations. I haven't but I've only owned 2. I've been a mechanic 28 years and never ran across it. Don't know anyone that has. I have come across bad and weak pumps on diesels but most my career has been working on gas engine vehicles. 

[Mopar1973Man]

I've seen where conditions were right and reduced power and kind not are strong. Hard telling if its a suction air leak or was it the steel lines next to the hot exhaust. Never has a hard start. Only occurred when it was hot out and pushing the fire truck hard up hill to the fire. Fine on cooler day and not pushing hard.

Edited June 30, 2019 by Mopar1973Man

[24Vdodge]

On 6/23/2019 at 8:31 AM, Mopar1973Man said:

 

Strange that FASS and AirDog both put pre-filters on and causes no strain on the pump. Is the might mechanical pump that weak because it nearly double the distance from the fuel tank now at the very front bumper? Hmmm... Pumps are not design to suck or pull fuel long distance they are designed to PUSH fuel. This is where the weakness is being the pump must be located at the crank and adding huge distance from the fuel tank and forcing the pump to pull fuel longer distances and add a prefilter would impact the pump performance. Yeah this is basic pumps 101. The suction side of the pump should be as short as possible.

 

And yet FASS and AirDog still have a pretty high failure rate (from my reading on the diesel forums) Haven't they both been redesigned a few times now in the last 10 years? Different motors, and revisions, etc. Hmmmmm, not as reliable as they once were. 

 

I had a old school FP100 air dog on one of my trucks back in 2006 to 2012, put 200k on that truck with the FP100, never one issue. I almost put a FP100 on my current truck, but after reading all the problems people were having with the air dogs back in 2012-ish on the forums, and after reading some revisions that air dog went through, I decided I didn't want to rely on a electric pump anymore, and I went with a fuel boss. I have zero regrets.  

 

My current truck has had a glacier diesel fuel boss, on it for 230k. It's hardly what I would call weak. It's simple and it flat works. It does not matter that it's mounted at the front of the truck. Fuel boss moves plenty of fuel. The bypass can be shimmed if you want it to pop off at different pressures.  I'm positive it will be on the truck for as long as the truck is alive. 

 

2nd gen trucks don't need the over filtered fuel like the 3rd gen common rail trucks do. Nothing wrong with a strainer between the tank and the fuel boss, and filter between the fuel boss and VP44. IMHO air dogs and FASS are over kill for filtering on a 2nd gen truck.  

 

 

On 6/20/2019 at 5:23 PM, Welcometmnm said:

Probably not a bad idea for a strainer. When I cut into the fuel fill hose, the inside was like it delaminated. 

 

Cut the fuel hose with a brand new sharp utility knife blade, or a set of shears. Then blow the hose out with compressed air afterwards, to make sure no chunks are left in the hose. 

 

This is bug catcher I run on my truck. 

 

https://www.glacierdieselpower.com/i-1140-fleetguard-ff5079-3-8-inline-strainer.html?ref=category:169

 

I have it mounted on the frame near the t-case. So it is between the fuel boss and the tank. 

 

Then I have one of these, between the fuel boss and the VP44.

 

https://www.glacierdieselpower.com/i-1224-98-5-02-dodge-ram-gdp-mk-10-big-line-kit-non-heated.html

 

It's simple and it works. 

 

 

On 6/23/2019 at 8:31 AM, Mopar1973Man said:

 

Strange that FASS and AirDog both put pre-filters on and causes no strain on the pump. Is the might mechanical pump that weak because it nearly double the distance from the fuel tank now at the very front bumper? Hmmm... Pumps are not design to suck or pull fuel long distance they are designed to PUSH fuel. This is where the weakness is being the pump must be located at the crank and adding huge distance from the fuel tank and forcing the pump to pull fuel longer distances and add a prefilter would impact the pump performance. Yeah this is basic pumps 101. The suction side of the pump should be as short as possible.

 

Further more, 1989-1998 12 valve trucks have mechanical lift pumps mounted on the block far away from the tank, PULLING fuel. Not but 30 inches of difference between the side of the block and front of the bumper. How often do we here about those pumps failing on 1989 to 1998 trucks? Almost never. 

 

I've owned five 1989-1998 12 valve trucks, I've logged well over million miles on those trucks combined. Never replaced a lift pump on any of them. Pulling fuel far away from the tank. 

 

IMHO if dodge/cummins would have kept the mechanical lift pumps on the 1998.5 to 2002 trucks, pumping, PULLING fuel to the VP44, instead of going to the problematic electric lift pumps like they did, all of these aftermarket companies like, FASS, Air dog, and yes fuel boss, would never of had the need to reinvent the wheel. 

Edited June 30, 2019 by 24Vdodge

[Mopar1973Man]

3 hours ago, 24Vdodge said:

 

And yet FASS and AirDog still have a pretty high failure rate (from my reading on the diesel forums) Haven't they both been redesigned a few times now in the last 10 years?

 

4G AirDog is a good pump. Just don't want anything to do with the 3G pumps those are the ones with serious issues. My old 2G pump ran for a very long time before failure. 

 

3 hours ago, 24Vdodge said:

Further more, 1989-1998 12 valve trucks have mechanical lift pumps mounted on the block far away from the tank, PULLING fuel. Not but 30 inches of difference between the side of the block and front of the bumper. How often do we here about those pumps failing on 1989 to 1998 trucks? Almost never.

 

I've replaced plenty. Diaphragm fails and the fuel starts pumping fuel into the crankcase. Another common is person changes a fuel filter or runs out of fuel and the primer lever is broken change the fuel pump to get it started. Not to mention the VE didn't require much pressure (about 6 PSI) or volume. (no high volume return). 

 

Edited June 30, 2019 by Mopar1973Man