I removed my oil pan today and found the oil pump pick up screen half full of crap. It was black and hard and I was able to compress it so no problems there. I have to say it was also in the bottom of the pan. I believe that this is also why the oil pressure was reading low on the gauge.

I also found 3/8 of an inch slack in my timing chain, I think it is too much. What do you think. Not that much more to replace.

The pan gasket was a one piece. Came right off and minimal cleaning. Also got the main seal gasket out, slide right out with just a little tapping on it. I have a new pump and will pick up a new pick up screen along with timing gears tomorrow.............The project continues.

Mike
1991 Cherokee

 

What kind of oil you planning on using?
Seems that rotella might help clean it up a bit.

 

I paid 1200 for this jeep last month, runs great but has been neglected. I changed oil in it when I first got it then the rear main seal started leaking. I'm lucky I can do all the work.

Thanks for the Rotella idea, never have used it.

Mike

 

Flow doesn't create pressure, resistance does. All the engine bearings are probably due for replacement.

 

Wish I had a photo to show you, if oil cannot get drawn into the pump quickly it can't circulate. Ive seen this before, not my first time in an engine.

Mike

 

What's it look like under the valve cover?

If the engine is running fine and there's no chain noise, I wouldn't worry about the timing chain.

 

If you have the pan off, it would be a good idea to check some bearing clearances with plastigauge. As for the timing chain, I tend to like less slop so I would replace it.

 

Exactly lack of oil tears up bearing. Resulting in low oil pressure.

 

That's what the inside of the 175,000 mile engine I got from the junkyard looked like when I installed it in my wife's XJ over 50,000 miles ago. New oil pump and screen, Rotella T3 with Marvel Mystery Oil and it cleans right up.

 

Oil sludge! Not changing oil regularly. Almost every oil pan I have pulled there is sludge in the bottom. For some reason seems like more on Chrysler engines. Clean or get a new pick up tube and put back together.

 

Good News Update!!!!!!!! Got the new rear main seal in, New Melling oil pump with new pick up screen and a new timing chain and gears. All is well and I have twice as much oil pressure as I did before. The new oil pump is a standard one NOT a high volume one.

This was well worth the insane hassle of doing this. It's not really a hard job, just hard to get too. Made a mess of my garage but I cleaned it today with Simple Green. Floor is clean and the garage smells like new again.

Mike

 

Cool. Thanks for the update.

 

Glad to hear the good news, Good pressure = Good Job!

 

Victory was yours!

 

Awesome good to hear!