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First Forum or thread

JoeyJacob

New Member
Messages
7
Reaction score
11
Location
Pike County Pa.
Well I just bought a 1995 GMC with the 6.5 turbo diesel. Only 100,000 miles. Truck in near perfect condition. It was a NYC truck used water down NYC diesel and rarely broke 45 mph. Was a real dog. Ran some good fuel and diesel conditioner. Now runs better but stalls occasionally right after I start it. I have to put pedal to the floor and it starts after about 30 seconds. Then it's fine but it occasionally spits an sputters at 50 mph or better.
I know nothing about diesels. Need to know what to do to get it so it does not stall and sputter. Then want to get a little more performance without spending a ton of money.
Thanks for any help.
 
Welcome to the forum.

Need to change fuel filter if you haven’t already and put 1/4” clear hose on the return coming off of the injection pump so you can see if you have any air in the system.

The drain T that AK is talking about should be a brass T unless someone has changed it to something else over the years. Now would be a good time to go to Leroy Diesels website and get it lift pump relay harness. It takes the load from the lift pump of of the OPS.
 
Welcome to the forum Joey.
First and easiest in diagnosis is as Jaryd suggested, install a section of clear fuel return hose off the injector pump, start the engine and then watch the clear hose for air bubbles. Bubbles in the fuel means a loose connection somewhere before the lift pump, if the lift pump is working as it should.
 
The clear line being mentioned: just clear tubing from any hardware store being sold in the plumbing department (sold for about $3 per foot at Ace in my town). All you need is a 6” piece of 1/4” id tubing. Get 2 new screw style hose clamps, the spring loaded ones doesn’t hold the tubing good sometimes.

There is some special things to learn about this engine - it has a bad reputation because most people dont know how to treat it different.
They misdiagnose it ALL the time- DONT go buying parts till you check here with proper tests. Right away shops will say new injector pump when it is rarely needed.

Keep temps at 210 or below. Never use starting fluid. Lots of parts show up as correct, but are the wrong ones to use like glowplugs for instance- again- check here before buying.

At 100,000 miles you need a new harmonic balancer- that is a major engine killing failure point- another part where lots are available- but many are a mistake. The best is fluidampr but expensive. The other choice is AC Delco. Many of us tried cheaper options that failed in under 30,000 miles. Learn from our (sometimes expensive) mistakes. Don’t put this off- crank and/or block breaker. Not part of any planned maintenance, so they wont do it in a shop by manual. Something learned from experience in a large fleet.

Let us know after you check out the lift pump pressure and clear line to watch for bubbles. -A small trapped bubble in the clear line is ok. A trail of bubbles is what you are watching for as problem indicator.

If you do better on the phone, lmk I will pm my cell.
And welcome btw
 
Welcome to the forum.

Need to change fuel filter if you haven’t already and put 1/4” clear hose on the return coming off of the injection pump so you can see if you have any air in the system.

The drain T that AK is talking about should be a brass T unless someone has changed it to something else over the years. Now would be a good time to go to Leroy Diesels website and get it lift pump relay harness. It takes the load from the lift pump of of the OPS.
Thanks go there and check it out. I don't know anything about diesels but everyone seems to agree on the problem. Once I get it running good want to look at someupgrades to give the truck a little more detail up and go
 
The clear line being mentioned: just clear tubing from any hardware store being sold in the plumbing department (sold for about $3 per foot at Ace in my town). All you need is a 6” piece of 1/4” id tubing. Get 2 new screw style hose clamps, the spring loaded ones doesn’t hold the tubing good sometimes.

There is some special things to learn about this engine - it has a bad reputation because most people dont know how to treat it different.
They misdiagnose it ALL the time- DONT go buying parts till you check here with proper tests. Right away shops will say new injector pump when it is rarely needed.

Keep temps at 210 or below. Never use starting fluid. Lots of parts show up as correct, but are the wrong ones to use like glowplugs for instance- again- check here before buying.

At 100,000 miles you need a new harmonic balancer- that is a major engine killing failure point- another part where lots are available- but many are a mistake. The best is fluidampr but expensive. The other choice is AC Delco. Many of us tried cheaper options that failed in under 30,000 miles. Learn from our (sometimes expensive) mistakes. Don’t put this off- crank and/or block breaker. Not part of any planned maintenance, so they wont do it in a shop by manual. Something learned from experience in a large fleet.

Let us know after you check out the lift pump pressure and clear line to watch for bubbles. -A small trapped bubble in the clear line is ok. A trail of bubbles is what you are watching for as problem indicator.

If you do better on the phone, lmk I will pm my cell.
And welcome btw
Thank you. Will not have time till next week to work on it but I will let you know what I find. This is first Forum I have ever been. Thanks to all of you. Its great to have a place to get good info.I really like this truck. Want to get it running s0. Change the harmonic balancer then do some performance mods if there are options that are not to expensive.
Thanks again will reach after I do the tests.
 
Hello I have been away for the better part of the last 2 weeks. Lots of great info. Did a lot of computer research. My big problem is health. I am all busted up and just cannot do most of my work anymore. How do you find a good diesel mechanic and especially one for this mot
 
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