'95 Cheyenne

[MrPink]

I'm glad to be here, lots of knowledge, helpful friendly members who watch out for each other, minimal nonsense.

Same here, but there is tons of shenanigan's lmao

 

[Cheyenne95]

A couple weeks back the oil pressure sensor failed, no lift pump; 6.5TD. Happy to get home, but hate that the injector pump had to pull its own fuel.

With that fixed, I'm wonder if the lift pump is getting weak. I attached a new, cheap fuel pressure gauge to the fuel drain line, and at idle it reports just a little above 5 psi. I expected closer to 7 psi. I read that running as high as 10 psi (some claim 15!) won't bother the injector pump and in fact is of benefit. I know it is not just psi but volume, but when the pressure drops way off, volume is too. Being a '95, my truck is ODB1, so if I was to feed it too much pressure, there is no ODB2 computer to alert me. For the 6.5TD guys, is 5~6 psi at idle too low? Especially since it will definitely fall off while cruising and accelerating? I was looking for a $200 good, dependable replacement for the notorious factory style lift pump. After a lot of reading and looking around, looks like there is no such solution. Have to spend $450 for a good, dependable solution. Ouch. Saving pennies and dimes now.

Next step is to pickup a few clamps and more fuel line so I can tape the cheap fuel pressure gauge to the outside of the windshield and take it around the block. Just long enough to see how badly the fuel pressure is falling off while cruising and accelerating.

As a permanent addition, I'm eyeballing the matching AutoMeter fuel pressure gauge to add to my truck. I'd like to know what the fuel pressure is doing at all times as a diagnostic instrument. A lot of people add the pressure tap to the top of the fuel filter housing. I'm not a fan of that. Looking at options.

 

[Erik the Awful]

I would be less concerned about lift pump pressure than injection pump pressure. If the lift pump is producing any pressure, it's keeping the injection pump fed. I also wouldn't be too concerned about lift pump pressure at idle, so long as there's some pressure. I think you're correct in wanting to know what the lift pump pressure is on the road.

 

[Cheyenne95]

Thanks Eric, I appreciate your input.

By chance do you have a lot of experience with the 6.5TD?

Thanks again.

 

[Erik the Awful]

None, but I've done a lot of light work on a lot of other diesels. 71 and 92 series Detroit Diesels, Cummins, Duetz, Continental, Petter, Lister, Yanmar, etc. The 71 series Detroits are the only ones I've been in deep on. In the shop I work in if we have a diesel engine failure, it's a remove/replace item.

 

[Frank Enstein]

I used 2 MRG-12D pumps in a row on my 6.5TD and it never ran better. My fuel tank shed the inner lining of the tank and clogged the sock killing the original pump.

Mr. Gasket 12D Mr. Gasket Micro Electronic Fuel Pumps | Summit Racing

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www.summitracing.com

 

[Frank Enstein]

Thedieselplace.com was a great help to me. They said 3 to 9 psi is the happy zone. Above 9 psi can be a problem but I don't remember why.
The 2 pumps running together pegged my 7 psi gauge!

 

[94K3500PROJECT]

Thanks for the compliment, I appreciate it. I try to include all details on the chance it helps someone. Plus, I can look back on it later when I've forgotten what I've done. I know I get long-winded and I apologize for that. 8)

I purchased my OBS in 2007, took me a year to find it. I do not plan to replace it. We are hoping to build a house within the next year, and the plan is to have my own barn/shop/space for tinkering. Three or four years after moving I'm hoping to repower with a Duramax. Until then, I need my 6.5TD to keep on rolling. I have plans to rebuild the front suspension. I thought I'd have it done by now, hopefully this fall. I have a set of injectors and glow plugs waiting to go in also.

I'm appreciative for gmt400.com. I'm a member of a local FWD club. It's forum has pretty much gone to the wayside as everyone moved to FB. Long live the forum.

Did you iron out decisions on front end parts?
I’ve spent some time compiling a list of, and buying the best available for these trucks if interested

 

[jgreen16]

Wow, how long is this truck? My RC longbed only has about a foot of space behind it when bumped against the front wall of the garage. No way I could fit this.

 

[Cheyenne95]

Thanks 94K3500PROJECT. I foolishly thought I'd have the front end rebuilt with brake upgrade way before now. Haven't happened yet. Fall weather is rolling in, cold and short days. Looks like I'll be working on it in the cold and dark. Just what I was hoping to avoid. Just being busy with life. It happens.

If I ever get to it, I'll post back how it went and what tripping points I encountered.