nada

I had the engine down to the block and heads and redid the entire engine compartment on my 71. It looks great. However. despite having the oil pan off, and spending all the time and effort to stop and repair all the oil leaks, I screwed up and missed one. The rear main is leaking (like a seive) and now I have to: a) tear it apart and do it myself (with a little help) or b) take it to someone and pay to have it done. I just don't want to go through the nut roll of dropping the oil pan and all that mess that goes with it. I'm considering talking to a trusted mechanic in my town and having him do it and get it over with. I have a couple of questions. Do any of you have a link to a site that explains how to replace a rear main seal with out removing the engine? Also, what should I expect to pay to have it done? I just can stand the leak. It is leaking from the weap hole in the bottom of the bell housing and the back of the oil pan (some). Thanks guys!

Rick in Tennessee :cheers:

Surfer69

You should be able to replace rear main with no problems. Just get one piece oil pan gasket and seal kit from Felpro. Might have to loosen idler arm to get pan out.

zwede

Are you absolutely shure it's the rear main seal? I have a small leak that shows just like yours (drops from the bellhousing). Mine is actually the rear of the intake and then it runs down the block. It's small enough to where I haven't felt the need to fix it yet. What tipped me off on mine was I can see a tiny puddle on the top of the block right where the block and bellhousing meets (just behind distributor). Afte r looking really close I found the oil trail down the side of the block.

If it IS the rear main, it's not hard to replace. I unbolt the pitman arm from the steering box and then there's enough room to drop the pan.

Recommend you get the one-piece fel-pro oil pan seal if you don't have it already. When installing the new seal triple check that the lip faces the right way (otherwise it will pump oil out!). Offset the two halves about 20 degrees compared to the block/cap split.

Paul L

Rick,
The motor does not have to come out. And you do not have to worry about a front Y-pipe.





It is a split seal.




[Modified by paul79, 11:34 AM 6/3/2003]


[Modified by paul79, 11:36 AM 6/3/2003]

hudman

Mine was changed with the motor in the car as well. It looked easy if you have a lift, the proper tools, etc. I sure would not want to do it myself in the driveway.

I had been living with the puddle in the driveway putting off the $250-$300 I had been quoted to fix the problem. Mine was not leaking badly, more an annoyance than anything else. Then, the oil pump went out which necessitated dropping the pan anyway. On mine, they had to remove the steering arm and the starter (I think) to get the pan off. After checking all the bearings with a plasti gauge and receiving a clean bill of health on the bearings, a new oil pump, a new rear main, and new oil pan gasket, I had no leaks. It was great.

Then 6 months later I spun 2 bearings and the motor had to come out! My engine builder said those bearings had been bad for some time, maybe 1000 miles or so (which is about how many miles I had put on the car since the oil pump failed). HMMMM-that is another story.

It sure is nice though having a leak free engine. Wonder how long my "new" engine will be leak free?

mapman

Detailed procedure in the year specific GM Corvette Shop Manual. The one piece Felpro pan gasket is a good idea.

jrzvette

I think Corvette fever ran an article about a year ago on replacing the rear main seal with the engine in the car.

Paul L

I do not know why you spun the bearings but - in general - replace the oil pump while all is apart. Cheap insurance.

isosceles

while all that is apart, is it difficult to drop the crank and put new rods and mains in? I think if I get that far in mine, I'd do those along with a new oil pump (Like Paul79 said) for insurance

hudman

The oil pump went out when the car was going down the highway at 60 MPH in the possession of the mechanic. They thought they turned it off in time, but they were wrong.

I agree, while you are in there, go ahead and change the oil pump. It is cheap insurance. In my case, I had to change the oil pump and while we were in there, changed the rear main.

Crash Dummy

isosceles,

Forget about dropping the crank while the engine is still in the car. It can't be done unless the tranny is gone and it's the absolute wrong thing to think about. Pull the engine if you want to go as far as getting the crank out. It is a good time to pull the main caps one at a time & inspect the main bearings. The rear bearings usually wear faster as that's where all of the load is. There is nothing wrong with punching the pistons out and referbing them while the engine is in the car though. There's nothing to it and probably worth your time just knowing you have new rod bearings & rings.


[Modified by bgrice, 10:16 PM 6/3/2003]

isosceles

Rick Church: Didn't intend to hijack the thread, thought it might be relevant to those in the "while I'm at it" mode of thinking.

bgrice: thanks for the response! Hmm, might do rods and mains and punch pistons out when I pull the heads for some flow work! Uh-oh....too much "while I'm at it" thinking! :eek: