Avanti Rear Main Seals

[bonehead007]

Well discovered my Avanti is leaking oil from the rear main seals. How easy/hard is it to replace them ? Does it involve dropping the transmission or can it be replaced with the engine/trans intact?

[JDP]

Not easy, but can be done in the car by just dropping the pan a loosening the main caps. They make a "Sneaky Pete" tool to spin the old seal out

[Gunslinger]

The '63 R1 I owned years ago had a very bad leak from the rear main seals. I tried a can of "Bearin' Seal" in the oil. It didn't stop the leak but sure cut it down maybe 75% or more. While not a correct fix, it did the trick until I rebuilt the engine a couple of years later.

I don't know if the product is still on the market, but something that does the same thing probably is.

[Studerick64]

I have found that it is usually the cork gasket at the back of the oil pan. It shrinks enough to leave gaps for the oil to drip out. I remove the starter drop the starter plate and clean the area with brake cleaner. I then run a bead of RTV along the filler gasket between the rear main and the oil pan, reinstall the starter plate and let it set up for a few hours before I start the engine. It wont always work but I seldom change a rear main seal.

[jlmccuan]

I had to lift the engine a couple of inches to get the pan to clear. But doable with the engine in the car.

[Rerun]

I had to lift the engine a couple of inches to get the pan to clear. But doable with the engine in the car.

I did my '63 R1 without lifting the engine. The steering bell crank has to be removed from the shaft, the bracket removed, and the tie rods drooped and pushed to one side. It's not as bad as it sounds. See the shop manual for details. BTW, on an R motor, don't forget to remove the PCV vent tube from the right side of the pan.

[nels]

I would double check to make sure the problem is the rear main seal itself. I've been fooled before thinking the rear was leaking when actually the oil was coming from the front main felt seal and running back the bottom of the pan and eventually dripping from the rear of the pan. The pan may just need snugging up or the cork gasket at the rear main, as mentioned in a previous post, may need attention. The seal replacement with engine in the car can be done for sure, but it isn't fun, especially if you're not 25 yrs old any more.

[bonehead007]

Thanks everyone for your help. Went with nels advice . Not 25 and it didn't look like fun so had someone do that and replace the freeze plugs that he could get at as one of them were leaking too. When I saw the car up on the lift and what he had to go through theres no way it was a NJ driveway job. He did replace the seal. Said the seals around the old one was hard as a rock so thats why that was leaking. Also the freeze plkugs were all getting too various stages of rusting out so replaced them with brass plugs.

Just out of curiosity, when he had the oil pan off, he pointed out that the inside walls of the engine block were painted orange. Anyone ever seen that or know why ?

[GinettaG12P]

Orange paint on the inside of the block could be glyptal - usually red, rather than orange - which is an electrical insulator that I often used to paint the inside of my engine blocks. The glyptal increases oil return to the pan and seals any casting sand that may be left in the block.

[StudeNorm]

When I bought my car last summer I got it home to find one casting plug leaking, so I replaced it right away. I park the car on a hoist in my garage so a few weeks later I noticed another plug leaking. This prompted me to check all the plugs and it seems someone in a previous life had replaced the 3 "easy" plugs and left the 3 hard ones untouched. Thanks a whole bunch.

I replaced the last 2 plugs and cleaned the water jackets at the same time. That would have been a really bullish job without the hoist.

I have since found my rear main seal leaking and it shows by running down the bell housing plate. I am not budgeted for a rebuild for 2 years or so, so I found a bottle of "rear main seal repair" 'in a can'... at Canadian Tire. Yes, that is what it is called. I can let you know in a couple of weeks if it has affected the leak or was an 11 dollar donation.

I would recommend a rebuild kit in the bell crank if you are removing to effect repairs.

The "rear main seal repair" product is made and/or marketed by Rislone.

[DEEPNHOCK]

Kudo's to you for doing all the grunt work while it was up in the air!!!

Did your guy rod out and flush all the coolant passage crud while the plugs were out?
Did he clean the oil pump pickup screen while the pan was off?
Did you have him take a look-see at the rod and main bearings?

Not nitpicking... But that's the ideal time to look at stuff like that...When it's accessible.

Thanks everyone for your help. Went with nels advice . Not 25 and it didn't look like fun so had someone do that and replace the freeze plugs that he could get at as one of them were leaking too. When I saw the car up on the lift and what he had to go through theres no way it was a NJ driveway job. He did replace the seal. Said the seals around the old one was hard as a rock so thats why that was leaking. Also the freeze plkugs were all getting too various stages of rusting out so replaced them with brass plugs.

Just out of curiosity, when he had the oil pan off, he pointed out that the inside walls of the engine block were painted orange. Anyone ever seen that or know why ?