Engine/Transmission (1994 - 1998) Stock truck specs

[EBramwell]

OK, I've got a (new to me) 97, 3500, 4x4, auto, with 160,000 miles. Everything is stock, except for the following things I have done.

The first things I did are:
1. KDP done
2. Overhead ran
3. Timing set
4. Gauges, pryo, boost, fuel pressure, trans
5. Overflow valve replaced (still had the original with 160,000 miles)
6. Fuel filter changed, and pre filter cleaned
7. Changed oil + filter
8. Replaced air filter with Nano air filter from Amsoil
9. Removed the CAT

Now that I have the gauges in and working I am seeing my fuel pressure running at 16 PSI at idle and 22 at 2500 rpm, while driving fuel pressure doesn't move from 16 PSI.
My Boost doesn't go above 20 PSI, and only hit's 20 PSI if I run it hard.
EGT's run around 600 under normal driving.
My lift pump ticks very loud, and I have wondered if it is starting to fail? The previous owner had the fuel lines replaced under warranty.
Also does my boost numbers sound right for a stock truck?
The previous owner never did any mods to this truck at all, all that was done was oil changes + filters.

 

[JFaughn]

Fuel pressure low , should be about 26 idle , high about 36 psi
boost about right
EGT under what conditions ?
replace lift pump .

 

[EBramwell]

That's what I assumed with the lift pump.
EGT's at 600 under normal driving conditions.
Thanks.

 

[JFaughn]

It would seem that something isn't right there , too much heat , with out seeing a lot of other trucks .
Mine runs about even with speed , if just maintaining / no load - 50 mph = 500* , 60 mph=600* , 70 mph=650* .
Usually high temps is either too much fuel , but your pressure is low , so next is exhaust restriction , turbo , cat , muff .

 

[tgordon]

Just an idea, but could it be an air restriction on the intake side, or even the waste gate being stuck open such that he would not get enough air. Or a injection nozzle being stuck open and leaking some fuel into the cylinder and it getting burned on th eway out?



I am just brain storming as I write.



Troy

 

[EBramwell]

I'm in the process of replacing the lift pump right now. I noticed that after removing the old one, that the springs are different. The new lift pump has a conical shaped spring while the old one is the same shape from end to end. The new one is a brand new one from Cummins. Has anyone seen this? Also does anyone no which end of the spring goes in toward the engine, the small end or larger end? Like a DUMB A** I removed it and didn't pay attention, I assumed it was like my old one, NOT.

Also I read here on TDR that it was easier to remove the spring and install the pump? Anyone confirm that? Wouldn't be hard to screw the top on with an inch of spring sticking out?

Oh and thanks for the good advice from you all.

 

[johnls]

My liftpump has ticked for 15,000 miles I have owned it. My fuel pressure was low when I bought it and installed a guage. I replaced the overflow valve and it solved the problem.

 

[EBramwell]

My liftpump has ticked for 15,000 miles I have owned it. My fuel pressure was low when I bought it and installed a guage. I replaced the overflow valve and it solved the problem.

johnls, the overflow valve was one of the first things I replaced.

 

[bmoeller]

Also I read here on TDR that it was easier to remove the spring and install the pump? Anyone confirm that? Wouldn't be hard to screw the top on with an inch of spring sticking out?

Main thing is to make sure the cam lobe is on the low side. If the lobe is facing you, you have to fight the spring. When facing away, there isn't as much pressure to push against.



The bolts are longer than the threads on the pump cap.

 

[bmoeller]

96-98 engine specs

 

[EBramwell]

Changed the lift pump, and now things are looking good.
Fuel Pressure is now 26 psi at idle, 36 at 2500 rpm with no load. :-laf