1957 Leaking rear seal

[bonneville]

Rear main seal leaking . I have read that this Is almost impossible to repair. Has anyone had luck with this issue? Any suggestions on the solution would be appreciated.

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[thessler]

I fixed mine doesn't leak a drop. Just put a new one in.
Tom

 

[1957Bird]

Engine in or out of the car? Can be done with engine in the car but certainly easier on a stand.
IMO. The only route to go is “ Prestigue Thunderbird “ kit.Quite spendy but in my experience, the only one that works. I personally did 2 before I bought their kit and that was the only one that did the trick.
comes with very detailed instructions.
patience will be your best virtue on this project. Good luck.

 

[doug7740]

Below is the article from the March/April 1996 Early Bird magazine will show you how to replace the rear main seal with the engine in the car.


doug7740
1955 Thunderbird Blue

 

[Tater Salad]

Isn't this problem mainly on the 312's? How much do they leak? Few drops a day, always dripping?

 

[bonneville]

This is a 312 engine. Leak is always dripping. Thanks for all the help.

 

[57tbird57]

Rear main seal leaking . I have read that this Is almost impossible to repair. Has anyone had luck with this issue? Any suggestions on the solution would be appreciated.

I have a 57 with a 312 in that was leaking all over the place. Heard about an oil adative called blue devil rear main sealer It had great reviews so i gave it a try. After driving it about a 100 miles, i went from several puddles down to a couple of drops. Also sealed power steering completely.

https://www.amazon.com/dp/B0079JX4JO/?tag=thunderbirdforum-20

 

[bonneville]

I have a 57 with a 312 in that was leaking all over the place. Heard about an oil adative called blue devil rear main sealer It had great reviews so i gave it a try. After driving it about a 100 miles, i went from several puddles down to a couple of drops. Also sealed power steering completely.

https://www.amazon.com/dp/B0079JX4JO/?tag=thunderbirdforum-20

Thank you. I will give it a try.

 

[Ward 57]

My rear engine seal has finally given up the ghost. Dripping like crazy. Have seen neoprene gaskets and CASCO sells them but they also offer an in-house designed rope journal seals like original and with elastomer side seals and also offer silicone seals supposedly designed specifically for the 312. I'll have my shop do the work but wondering if anybody has any experience with either?

 

[57tbird57]

You could try a bottle of Red Devil sealer. It did wonders for my Bird.

 

[Ward 57]

You could try a bottle of Red Devil sealer. It did wonders for my Bird.

I checked the ratings. Some were good, some said it did nothing and some even said it made their engine smoke like crazy. I guess it depends on the condition of the seal at the time.

 

[57tbird57]

I checked the ratings. Some were good, some said it did nothing and some even said it made their engine smoke like crazy. I guess it depends on the condition of the seal at the time.

My 57 312 was leaking like a seive,when i bought it from multiple locations. After adding a bottle and following sections, i am down to a couple of drops after driving for awhile. I was pleasantly surprised how good it worked. Saved me alot of grief and money. By the way, there is no smoke.

 

[Ward 57]

My 57 312 was leaking like a seive,when i bought it from multiple locations. After adding a bottle and following sections, i am down to a couple of drops after driving for awhile. I was pleasantly surprised how good it worked. Saved me alot of grief and money. By the way, there is no smoke.

I'm happy you had good results. I did a little more research and apparently it works on rubber and other neoprene seals and it softens them and apparently does a decent job but on the older 'Y' block engines with the rope rear seals it is ineffective as there is no rubber or other pliable material to recondition.

 

[paul5456]

Best Gaskets sells both a neophrene seal and a rope seal . Both have had good marks.

 

[Ward 57]

Best Gaskets sells both a neophrene seal and a rope seal . Both have had good marks.

So do several other parts suppliers. Apparently the new rope seals have advanced to be much more reliable and forgiving. The earlier neoprene seals were re jiggered from Chrysler seals but the new ones are much better and easier to install with the engine in place.
I'll let my tech decide which is the best way to go and if trying to replace with the engine installed or pull it to do the job on a jig and then if so, may as well replace the ancient mounts in the process. I think the end result will be better even though more expensive but better quality controls. Quality is the goal and not the cost.

 

[Frankie the Fink]

I put Blue Devil Oil Stop Leak in my 63 Corvette and the rear main seal leak stopped after about 150 miles;
These modern additives aren't like the ones from back in the day; they contain compounds to permanently swell seals and gaskets a bit and can often stop leaks for good.