Author Topic: Oil leak from alternator bracket to block securing studs - maybe  (Read 1454 times)

georgem

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Hi

I have a small but persistant oil leak from the area around the two studs that secure the alternator bracket to the lower(?) block.
I have the alternator off for repairs so was going to try and fix the leak. Are the holes drilled right through the wall of the block then tapped or are they only into the wall with no complete penetration

The oil is coming from above the  sump so I think the join/gasket is ok.

Thanks
George McDonald
Brisbane
230 Sl
1973 VW Kombi Single Cab Ute
2022 Volvo XC 40 Pure (100% electric)

ja17

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Re: Oil leak from alternator bracket to block securing studs - maybe
« Reply #1 on: January 25, 2022, 05:05:46 »
Yes, at least one of those hose is through drilled into the oil sump. You can get an oil leak if the threads are not sealed.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Benz Dr.

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Re: Oil leak from alternator bracket to block securing studs - maybe
« Reply #2 on: January 25, 2022, 05:11:18 »
I don't think they're blind holes. Use some thread sealer if you remove the studs. There are three holes in that area but only two are used on our cars. The back hole is pugged with a cap screw and I forgot to install it one time. Huge oil leak that prompted me to pull the engine thinking something serious had happened. When I saw what it really was, I was determined not to make that simple mistake ever again. So far, I never have.
1966 230SL 5 speed, LSD, header pipes, 300SE distributor, ported, polished and balanced, AKA  ''The Red Rocket ''
Dan Caron's SL Barn

1970  3.5 Coupe
1961  190SL
1985   300CD  Turbo Coupe
1981  300SD
2013  GMC  Sierra
1965  230SL
1967 250SL
1970 280SL
1988 560SEC

georgem

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Re: Oil leak from alternator bracket to block securing studs - maybe
« Reply #3 on: January 28, 2022, 20:45:57 »
Thanks Joe and Dan

Yesterday I removed the bracket and the two studs. A piece of wire told me that the front stud hole doesn`t go through the wall of the block but the rear hole does and I suspect that was where the oil was coming from as there was no trace of thread sealer. There will be when its replaced ;D

Thank for responding and helping.
George McDonald
Brisbane
230 Sl
1973 VW Kombi Single Cab Ute
2022 Volvo XC 40 Pure (100% electric)