mtm1516

I've got a 98 grand 4.0. Anyone ever attempted an oil pump?? Anything special I need to do, or need to know??

Bustedback

Why are you wanting to replace the oil pump?

mtm1516

I've checked oil pressure with an external gauge. Its shot for sure. I have no desire to do the job for sure. Just don't want to pay someone to do what I can do..

Bustedback

The oil pump does not make oil pressure, it makes flow. It's the tight clearences between the cam, crank, and rod bearings that make oil pressure. If those clearences get to be too much then you will lose oil pressure, that means the bearings are worn out. But you could have a supply problem before the pump, like the oil pump pick up is clogged with sludge and junk. I would pull the pan off and take a look at the pick up and bearings, but only after checking the oil pressure with a mechanical gauge first.
Replacing the pump is pretty easy, getting the oil pan off is the hardest part. But I don't think the pump is the only problem.

mtm1516

So. I did the pump. Now, when I give it gas, it get a ticking sound. Almost like the pump isn't lined up right. Oh, and I got the drop in pressure again too.

Bustedback

Did you prime the pump before starting the engine? Did you make sure the shaft on the distributor and the shaft on the pump meshed? Did you happen the check the main bearings and rod bearings while you had the pan off? How many miles are on this engine?

mtm1516

it was a jyd engine that was in it whe i scored it. before i installed it(the pump) , i pre checked the pump, and just before starting, i bumped the starter over several times in an attempt to ensure something like this wouldnt happen. In your experience, will the pump just line right up? Or did i screw it up?