93 K3500 6.5 Question

[weazel]

Going to pick up a 93 model 6.5 K3500 in the next couple weeks. Would like to get the 6.5 running decent enough to use the truck for a little while while I get my spare cummins out together.

Problem is, it is kind of a pain to get it started, when it does, it hazes white smoke and idles really rough. Previous owner says it'll clear up just a little bit but not much more and will continue to idle rough. They have replaced the lift pump, and their mechanic is thinking it's the mechanical injector pump. Any ideas?

Here is a video of it.

http://s625.photobucket.com/user/we...73-4E07-A064-5C95F1F88E61.mp4.html?sort=3&o=0

 

[zf>allison]

Did u try cracking each injector? Might be a miss on one cylinder

 

[weazel]

Not yet. I went to look at it to see if it's a project is want to do, and didn't really do any troubleshooting while I was there. As soon as I get it here to my house, I can start looking into it further.

But for now, you're thinking it could be a problem injector related?

 

[zf>allison]

The rough idle could be a bad injector, or a few other things, that's just where I would start. Easy to check, if u crack one loose and it doesn't change the idle then it could be a bad or stuck injector. Luckily everything for the old Idi is way cheaper than a dmax.

 

[weazel]

Ok, when I get the truck, I'll start there. Thanks for the help!
And yeah, that's very true lol

 

[THEFERMANATOR]

I would start with a compression test, but if I had to guess I would say injectors. Most dont do them, but they should be done at least every 100k miles. Problem is when they get worn and dribble, it allows fuel to drip out when the engines off, that fuel drops down and sits on the piston crown down into the ring land, and when you fire it up, you get the heavy smoke, and that puddled fuel acts like a blow torch to the piston crown when it does it. I have my old 6.5l with 5 torched pistons from bad injectors, had 153k miles on it.

 

[Chevy1925]

I would start with a compression test, but if I had to guess I would say injectors. Most dont do them, but they should be done at least every 100k miles. Problem is when they get worn and dribble, it allows fuel to drip out when the engines off, that fuel drops down and sits on the piston crown down into the ring land, and when you fire it up, you get the heavy smoke, and that puddled fuel acts like a blow torch to the piston crown when it does it. I have my old 6.5l with 5 torched pistons from bad injectors, had 153k miles on it.

wow, my dads old 93 must have been lucky. he had 280k on it before he sold it due to the original trans finally giving up the ghost. most he did was glow plugs and the awesome oil pressure sensor that cuts the fuel out cause it was known to go bad.

 

[weazel]

I've got my fingers crossed it hasn't gotten that far and melted Pistons lol.
The truck has 193k miles on it, and they said they've never had the injectors done, so I'm betting you guys may be right. Just hoping they haven't taken out any Pistons yet so I can get some use out of it until I get all the cummins stuff together and done...

Thanks for the info so far guys, now I know which troubleshooting step to try first instead of the good ole, just throw parts at it method lol

 

[weazel]

Finally got the truck home and messed with it a little. Cracked all injectors on the drivers side, had immediate response from the engine. I could only get to the front injector on the passenger side, but the idle changed after messing with it too. There's a heat shield above the two injectors under the turbo, and I couldn't really get to the injector to the rear due to the ac lines, and the wrench I was using..

I saw a couple of videos on YouTube the other day, and the guy found a broken valve spring. I'm beginning to wonder if that's really the problem? The valve cover gaskets leak anyway, so I may attempt to pull them and have a look and see what it looks like in there.

 

[THEFERMANATOR]

The rocker arma are held in place with nylon buttons, and they are notorious for breaking and making all kinds of racket.

 

[weazel]

Well, a week or so back I went to change out the 4wd actuator on the differential. I heard dripping under the truck, so I looked and saw diesel dripping off the rear of the engine.

Fast forward to today, took time to pull the intake off and see what's leaking. Found the bottom of the filter housing to be leaking, and also the drivers side of the injector pump. Could the pump leaking like this be the initial issue I had with this thing idling bad and white smoking?

 

[zf>allison]

Could be maybe of its sucking in air, there's a small access plate on the drivers side of the pump. That's what the fuel screw hides behind.

 

[weazel]

I found a good used pump that I'll pick up and install.

I checked the oil, and it felt a little diesely.. So I think I'm going to find some injectors and swap them out too