PE Pumps being investigated

[Ncostello]

After emailing PE about their pump line and asking a couple of tech questions regarding the bypass systems... they responded with this statement.



"Please excuse our long delay in getting back to you. We have been experiencing some problems with 4100, 4200 & 4300 pumps when used on the Dodge diesel. For the time being we are suspending sales of these pumps for this application until we have solved the problem. Please contact us in future (30-45 days) for an update. "



Not cutting the pump down at all... in fact I think its the best thing going as far as aftermarket pumps. Who else is attempting to solve any issues for the Dodge diesel application? This should be considered a credit to their dedication to our needs. When was the last time DC, Cummins, or Carter wrote anyone back and said "we are solving the problem".

 

[Ncostello]

Moderators... I mistakenly posted this in the wrong forum. Could you please move it to the Products/Accessories Engine Transmission. Sorry about that.

 

[15w40]

When I purchased my PE4200 from Product Engineering, I was warned about how there have been some failures due to water entering the motor, and PE suggested mounting the pump on the firewall to keep it dry. Being one who never follows directions, I chose to mount the pump in front of the tank after sealing it with silicon RTV. Then I read that there have been problems with the pump over heating and the RTV may make it worse. After seeing Ncostello’s photos of the fuel pick-up assembly I decided not to install a pre-filter. The pickup already has a fine mesh filter on it.



I have been playing with the 4200 for about 3 months on my test bench before installing it in my truck. It will draw almost 9 amps when fully loaded, like when the truck is at idle and the pressure goes to 20 psi. That is about 125 watts of power and the motor gets hot. At WOT when the VP-44 is drawing fuel, the pressure drops some and the motor current also is reduced, but it still gets hot.



A while back I posted in my reader’s rig section about a circuit that slows the lift pump down so it is not running at full speed all the time. This circuit uses a PWM technique that controls the pump speed based on a pressure sensor added to the fuel filter. At idle the pump is drawing 3. 5 amps and the pressure is set to 7. 5 psi. At WOT the pump draws about 6. 5 amps and the pressure stays at 7. 5 psi. I have not yet used the full fuel flow capabilities of the PE4200. I am only mildly bombed making about 400 HP with RV 275 injectors, an original VA box and Blue Chip’s APB box. What I have discovered is that the only time I cause the PE to rev up is when I am making smoke. 90% of the time is running at about 1/3 of its capability and stays cool to the touch. It is too soon to tell but I am hoping the pump will last for a couple of hundred thousand miles.



PS.

If anyone has trouble reading the info in my reader’s rig section, I can send a higher res. JPEG

 

[Ncostello]

15W40...



I've began to notice that my truck will now remain in the 14psi range most all the time. At idle I'll go past 15. Under load I'll get in the 13's. I've also noticed that most of my loss comes after letting the clutch out and taking off from stop lights. During that acceleration, I'll see down to 13. 4 or so. But I have also noticed that I'll go from say 13. 8 back up to around 15. 2 under a 5th gear pedal to the metal run up a long steep grade... which is about as close as I can get to loaded up. Funny that it will recover under these conditions but wont "recover" so easy around town. And by recover I mean the pressure will actually go back up during the event rather quickly. I cant get it in the 12's no matter what I do. Maybe a trailer would help that... I'll have to try that out. All in all its as close to a constant 14psi as I could have hoped for. And its not all over the place either... its very predictable as to what the gauge will be reading based on my conditions.



Anyway your setup is looking great too. Your diagrams are very good.

 

[15w40]

I think the pressure fluxuation you are seeing in around town driving is caused by the dynamics of the fuel system. When stopped the velocity of the fuel in the fuel lines is slow. The pressure may be at 15 psi but the flow is low and most of the pump output is being recirculated through the spillback valve. As you floor the smoke pedal, the flow tries to increase quickly causing the partial vacuum on the inlet of the lift pump to increase. This vacuum increase will cause pressure to drop on the output side of the pump until the fuel speeds up. The spillback valve will not close immediately because it acts to keep a delta pressure of about 15 psi between the suction and discharge side of the pump. If the vacuum increases by 1 or 2 psi on the inlet side, the output will follow by decreasing 1 or 2 psi. As soon as the vacuum is relieved by the fuel flow catching up to the demand, the pressure recovers. At high speed when the fuel flow is higher, flooring the pedal only calls for a smaller increase in flow. This will show up on the pressure gauge as a smaller dip before recovering. What you want to watch for is when your pressure does not recover quickly. This may indicate a pump problem. Last winter in the cold, I could easily pull the pressure down with the Carter pump in the stock location. It took seconds to recover because of the viscous fuel. It was not easy to increase the fuel velocity in the cold.

 

[jjohn]

Originally posted by Ncostello

Who else is attempting to solve any issues for the Dodge diesel application?

Who else? < Read the coming soon part at the bottom of the page.

 

[Ncostello]

I guessed there was a fluid dynamics situation occuring inside there and the recovery process was part of the systems nature. But I had no idea to what extent. I realized it was normal as the pump is in one location, the VP in another, and the sending unit in the middle (post final filter). Guess I really wanted to stress that the line size and lack of high friction loss fittings probably allows it the ability to recover and keep up near the high end of what the pump can do. Seems on stock systems the VP is able to pull enough out of the banjo equipped lines that pressure will fall and stay at lower levels until the pedal comes back up. No big deal as all positive pressure is good anyway.



I also notice that fillling up the tank now makes no noticable difference in pressure as it used to. In fact some of my highest idle readings come at around 1/2 tank. And I'm only talking maybe 0. 5 psi difference if thats really measureable anyway with accuracy. But all is good and I'm convinced if my Carter pump is gonna live its now or never.