Sick 6.2 diagnosis
 

Hi all, I've got an 83 K5 Blazer 6.2 diesel. I'm working on getting her fixed up and back up to speed. Having some engine issues at the moment. Curious what you all's diagnosis is.

Here's what's going on with it.

I got a rebuilt fuel injector put into it recently since the old one was seeping or apparently going bad. That didn't really help things and in fact it idles pretty rough now.

It has and always has since I bought it (2,000 miles ago) pretty bad blow by. I imagine the engine has 250,000 + miles on it by the odometer. No way to tell though for sure.

It smokes upon start a lot worse since the new injector pump. I ran some kerosene mix through it and that seems to help some.

Either way it's really doggy and was with the previous injector pump too. To the point of dangerous getting on the interstate. I'd say 0-60 mph in about 35 seconds.

At speed though I don't really have any complaints, engine sounds fine to my greenhorn ears.

The diesel mechanic I took it too after the injector install said he's been working on diesel engines for 2 decades and this one has him 'stumped'.

He wasn't too confident with the O'reilly rebuilt injector pump and thinks that could be it, or it could be installed wrong, although he mentioned it would have to be installed waaaay wrong to get it to run the way it is.

Other people think it's the injectors (hence the kerosene to try and burn stuff out). The previous mechanic did note some seepage around the lift pump too but it's working at the moment.

Anyway, would love to hear any comments on what you all think the problem could be. Just looking to get another 50,000 miles out of this engine. Then it might be time to get a different engine.

I would do a compression test on each of the cylinders, if its a high mileage, check all of the cylinders have even compression, at least 170 lbs psi, if you have a low one try adding some engine oil and if the pressure goes up its the piston rings.

Another thing to check is the injector pump timing, make sure the line on the pump and the casing are opposite each other if they are not this will cause a lot of smoke, in all ranges. Sounds like you don't have any power if its taking 35 seconds to get up to speed. Another thing to check is the EGR valve this will cause a lack of power also below 2000 rpms......one last thought check the PCV make sure its not blocked, or damaged. Let us know how you get on.