I have a 1985 Camaro 2.8L 5 speed. Basically stock. We rebuilt the engine because it spun a bearing. Put in an ARE crank kit, which came with bearings. Engine has all new bearings, lifters, standard volume/pressure oil pump, and rings. We didn't make any modifications...

The oil pressure is 10psi idling hot and about 25 psi at 2000 RPM hot. Oil is 15W-40. I consider this pressure to be adequate, but it seems kind of low. What do you good folks think? I kinda wonder if I left out a seal somewhere.

 

I'm gonna tell you something that you may not want to hear.

I used to sell engines and engine kits an auto parts store. The most troubling? The 2.8V6 GM. The reason? These engines were plagued by oiling problems from 1980 until mid year 1986. Every year has a different spec for the crank/rods/bearings setup and if it's not matched right, you get the condition you have. I would suspect a spun bearing to happen next.

For future reference only use a block from 1987 or newer when dealing with ANY 2.8, whether it be FWD or RWD. All 87 and up blocks and cranks are produced with the upgraded oiling passages and bearing sizes.

I don't know what to tell you about where you're at now. Maybe everything will be okay...

When it blows up, go to the wrecking yard and get an 87 or newer 2.8/3.1/3.4 from either a 3rd gen car or an S-10. Those engines frequently get over 200 thousand miles on them before they need to be torn down.

Good luck, man...

P.S. My oil pressure was 45psi+ hot AFTER 200k miles on my 90 3.1 bird and 88 2.8 S-10...

 

All I know is that when I primed my engine, it was 60 psi (attached the shaft of a distrib to a drill).

 

Yep.

That 3.1 is a great engine! It will serve you well for a long, long time.

 

KrisW,

Would a high volume pump help? The parts guy at A.Z. was very much opposed to it. He said it was too much oil for this engine.

My son has this car at college and is 1300 miles away. If I am going to make a trip to help him fix it, I need to make sure it is right the second time...

Funny, we didn't have the money to do it right the first time, but now we will have the money to do it again.

Thanks for all the replies. I really appreciate it.

Jim

 

Sorry, man, the stock oil pump is the best thing for these engines. They flow so well that a high volume pump is not necessary.

The problem you are having is that your crank and bearings are not fitting the block properly. You have an excessive clearance problem and that is what is causing your low oil pressure problem.

At over 200k miles, my oil pressure was higher at an idle than what you have.

15/40 is great oil. That's not the problem. Your problem is that you need to start with an 87-up engine block.

I told you that you wouldn't want to hear this. I just don't want you to get steered into the wrong direction. I know you've got a lot invested now, but trust me when I tell you that an 87-92 long block, even used with high miles, will probably last longer than a rebuilt pre-86 2.8 will. Your engine block is flawed in the oiling department from the time it was made. It's not a bad design; they just had to figure out the proper oiling and that involved engine block and crank mods every year until mid 1986.

Good luck man

 

Thanks for the response. I think I left out the o-ring between the rear main bearing cap and the block. It is still in the gasket kit I have in the garage. Hopefully, installing that will help. I guess I need to find a good 3.1 to put in its place. I was gonna do that initially and decided not to.

You were right...I didn't want to hear it. Sometimes the truth is not what we want to hear. I wish I had asked before we rebuilt it. thanks again.

 

No problem man. I hope your o-ring is the answer. Whether it is or not, keep posting because there are lots of new guys who will benefit from your experience. Even a few of us "veterans" will like to have that knowledge to save for future use.

Let us know how your project turns out!!

 

Here's where it stands now. He took the car to a local mechanic and told him the history. The mechanic put his oil pressure gauge on it and drove it around town. They observed 15psi hot idling and 20psi hot 2000 rpm. We are going to call this adequate until I can get down there to help him dig into the o-ring. I told my son not to let the oil level get down more than half a quart. If he sucks any air at all, the game is over.

Thanks again for all the help. It might actually be cheaper to just build the 3.1 than go down there to fix the 2.8... There's a thought.