2nd Gen Non-Engine/Transmission My Truck Hates The New Ulsd Fuel!!!!

[WestTN]

Several pages back JoeG posted his fuel pressure readings. Joe, I would be VERY concerned that if the filter did begin to clog that so much pressure would just collapse the element and deliver unfiltered fuel to the VP. I think a good pressure regulator would be a great addition to your system.

 

[Joe G.]

I disagree. The P7100 fuel system and filters will take a lot more pressure than what I have. From what I have read some of the competition trucks are running quite a bit more pressure. So far I have never read that one of these systems experienced such a failure. There have been clogged filters from bad fuel. If the lift pump is in good shape it will make a lot more that 40 PSI in that situation. Remember, the overflow valve is AFTER the fuel filter on a P7100 system. The overflow valve is what regulates fuel pressure in these systems. The other limiting factor is the strength of the big spring in the lift pump. The fuel is NOT driven by the lift pump push rod. The push rod compresses the spring. The spring is what pushes the fuel. So the max pressure the lift pump can make is determined by the strength of the spring. I'm sure that the max pressure situation has occured many times because of a clogged filters on these trucks. I suspect that the way the lift pump is designed is to prevent damage in the case of some sort of stoppage in the fuel system.

 

[VHolloway]

well put it sounds rite to me

check out diesel power magazine read and learn

if you know of some other good diesel magazines let me know I love to read

what ever I can get my hands on about diesel engines fuel ect

but that filter can being loose was a trip

that was just luck I found that new filter back on tight and she runs smooth as silk

 

[Katmandu]

I don't know if it would be a breach of company policy to post them here. I will check and get back with you, it might be awhile, we have been hit with quite a snow. It will take me a day to dig out of my house, I am off on vacation, and glad of it. .

Hope your digging out is going well. WATCH your BACK!! I've had enough snow shoveling to last me a lifetime!

Anyways, you could just xxxx out your Company's name etc... I'm curious as to ULSDs lubricity factors over LSD to be specific.

Is it really necessary to run additives in a 12 Valve P7100 equipped engine ?

 

[Champane Flight]

Not really....

Hope your digging out is going well. WATCH your BACK!! I've had enough snow shoveling to last me a lifetime!



Anyways, you could just xxxx out your Company's name etc... I'm curious as to ULSDs lubricity factors over LSD to be specific.



Is it really necessary to run additives in a 12 Valve P7100 equipped engine ?

Lubricity on LSD was running around 300, our ULSD is around 380. The LSD was getting some lubricity additive also, just not as high a dose. I would not think you would need a thing in the old twelve valves, the only thing lubricated by fuel are the injector faces themselves. The pump is being lubed by engine oil. I can only speak for our diesel fuels lubricity levels, I still think the cetane is low for a ultra clean fuel of the future :-laf . I would like to see 50... That and cold weather is the only reason I add cetane booster, and diesel modifier.