My brother got a lemon on craigslist and wants me to help him. 2002 Blazer, 4.3 Vortec, 2wd. After a week the check engine light came on and it says its running rich. An engine pulley started squealing and oil pressure reads 0 at idle when the thing is warmed up. Never overheats. I told him its probably either his oil pump or his engine bearings. Did an oil change and it was dark and sludgy. I don't know if they did something to it to hide the problems or if a bunch of metal shavings came out but there was a lot of it that came out. I mean like it seemed like a handful. I am wondering if the front end took a shot and they covered it up and sold it real quick.


Anyways. We wanted to try to change the main bearings and oil pump ourselves but it seems like you have to pull or lift the motor to get the pan off. My question is can you release the motor mounts and lift the motor 3-4 inches to get the pan off or do you have to completely remove the motor out of it. Also, if we get the pan off do I have to remove anything inside the motor to get the oil pump off and bearing replaced.


I have looked all over youtube and forums and haven't found a lot of detailed information on this. I told my brother that this is just to fix the oil pressure and I don't know if this is going to fix the engine running rich or not. After reading a lot of posts, watching videos, and looking at all the problems, I don't know if we might be better off just replacing the motor because I don't want to waste his time and money.

 

Even replacing the motor wont cure the rich mixture issue. I do now that on 4x4 models the engine needs to be raised and half the differential assembly needs to be removed to make clearance for pan removal but I'm not sure on a 2 wheel drive model. The fact that you have metal shavings in the oil does nt bode well for that engine. It usually meens bearings are gone. If that is the case you need to find out which bearings, could be mains could be rods. In any case sounds like the engine need to come out any way so you may need to consider that. Me personally, If i ever saw that in the oil i would do a rebuild with out even considering going through all the work just to change the pump. 0 oil pressure is a pretty good indicator that the bearings are gone. Not just a pump issue.

 

If u lift that motor for any reason, make sure it's to scrap it!!!I wouldn't bother with that motor...U are far better off trying to find a low mile engine from a bone yard!!! Of course the rich running condition, could very well related to the spider inj assy. As these are a known issue with these motors.

 

I went into the upper intake and checked the spider injector out for the running rich problem. Took all the plugs out while it had pressure and non of them were leaking. The thing that struck me odd was that it was pretty clean in there. I replaced the fuel pressure regulator just because they are known to have some problems. I haven't changed any O2 sensors but that's because I figured I would get a code for those if they were the problem and not just the running rich code alone.


But yeah dropping in a different motor or using it as a trade in might be his better options and it saves me a really big headache.

 

I personally would put a different engine in it. Especially if it has no oil pressure at idle and it had metal in the oil.

As far as the running rich goes the cleanliness inside the intake plenum is usually caused by a leaking injection unit. The gas will clean the carbon right off. This is a common problem with these engines.

I don't think that you will be able to change anything in the bottom end if the engine without pulling it out.


Just my .02. Hope it helps.