I'm now in the diesel club w a 99 6.5L HO engine - help

[DeadheadNM]

Just completed a deal for a 1999 K2500 GMC Suburban w a 6.5L HO engine that has 42k total miles. It's a rig that I 'm getting directly from a fire department and it's been well maintained.

I've read these 6.5s can benefit from relocation of the pump mounted driver (whatever that is) and are prone to harmonic balancer failures. Any advice on what steps to follow or aftermarket items to purchase in order to keep the engine running reliably for many miles?

[Dieselwrencher]

Nice Pete! 42k is pretty low miles. Luckily, I haven't worked on one of these for years. The biggest problem these used to have was the fuel pump drive module would always fail. The originally were mounted on the side of the injection pump. They would get hot, over heat and fail. The fix was to install a heat sink plate and relocate the module to another location to help keep it cool. Here is a good description of the mod.

https://www.dieselhub.com/maintenanc...elocation.html

I'm not sure which ones are the best to purchase these days. I can check into that. These are decent engines just don't expect a lot of power from them with a long life. I know guys, and have read online a lot about it, that turn the boost up or put a bigger turbo on them, and it's a matter of time before the magic smoke and parts come out.

You probably want to run a fuel system lubricant in it every few tanks of fuel to help keep the injection pump alive. These were designed when sulfer was still in the fuel and I know the ulsd doesn't help those injection pumps. I like to use stanadyne fuel system treatment. You can usually get it at local parts stores or it is available online.

https://www.google.com/search?q=stan...client=gws-wiz

On the harmonic balancer issue, I'm pretty sure you will have to remove the crank pulley and inspect the rubber to determine the condition. Otherwise if you feel/hear any vibrations or bird chirping sounds while it is running, it is probably okay. Usually front main seals leak and saturate the rubber which breaks it down and starts the separation.

[DeadheadNM]

Awesome Ryan thanks so much. I also read something about oil lines that can separate at a C clamp and that aftermarket replacements with compression fittings are available. I’ll address all the issues you raise. I was hoping to run a Diesel engine free of any additives/fluid but the lubricant won’t be too onerous. Apparently Hummers used this same Diesel engine.

[Killer Bee]

congrats! no pics?

fun to to tinker on but after a few hmmwv water pumps I'd rather have a root canal

but seriously good luck and folks like Ryan know the tricks the factory left out..

[Dieselwrencher]

Originally Posted by DeadheadNM

Awesome Ryan thanks so much. I also read something about oil lines that can separate at a C clamp and that aftermarket replacements with compression fittings are available. I’ll address all the issues you raise. I was hoping to run a Diesel engine free of any additives/fluid but the lubricant won’t be too onerous. Apparently Hummers used this same Diesel engine.

Speaking of additives, you will want to run anti gel when it gets cold up there. I'd start when it gets around 25* or 30*. Make sure it is bio fuel compatible especially if Wisconsin is anything like Iowa. Bio fuel will gel sooner than conventional. It wouldn't be a bad idea to drain the water drain on the filter housing and replace the fuel filter before winter as well. You'll usually know soon if the glow plugs aren't working and locate the block heater cord. Even if it starts good in the cold, it is nice to have warm heat sooner. Some of them take a long while to warm up when its cold out.

[DeadheadNM]

Thank guys. Here's a link to a few photos: https://67-72chevytrucks.com/vboard/...7&postcount=30. I'll get a thread going on the truck soon. It should be arriving today. Ryan I'll definitely be picking your brain as I go forward and eally appreciate the advice. I'm totally clueless with diesel engines but eager to learn.

[DeadheadNM]

Looks like the PMD/FSD was relocated. I think that’s what this module is anyway

I started a project thread that I’ll add to as I go: http://67-72chevytrucks.com/vboard/s...d.php?t=821683

[Dieselwrencher]

Yes sir, it looks like it has been done already. One less thing for you to have to do.