Lotus Elan

Oil Leak at alternator bracket

PostPost by: William2 » Thu Jul 13, 2017 2:46 pm

I seem to have an oil leak that appears around the lower alternator bracket that bolts to the block. Does anyone know if these threaded block holes go all the way through the block? If this is the case should the two bolts be coated in Wellseal or similar to seal the thread and prevent oil seeping through?
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PostPost by: JimE » Thu Jul 13, 2017 8:19 pm

Not to my knowledge.
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PostPost by: NickD » Thu Jul 13, 2017 9:35 pm

The mounting bosses all have blind holes (or, at least, did originally). However, these engines can blow a small amount of oil out of the dip stick tube which then collects on the alternator bracket below the mounting bolts. This can be hard to trace as there probably will not be much oil around the tube. As least you can easily check if this is the cause by wrapping some tape around the tube / stick joint as a temporary seal.
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PostPost by: rgh0 » Fri Jul 14, 2017 9:17 am

Plenty of opportunity for leaks in the area from the front cover, sump and dip stick tube. Unlikely to be from the bolt holes but I have had a block crack at the threaded holes bosses and if these cracks go through then a leak could occur.

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PostPost by: nigelrbfurness » Mon Jul 17, 2017 8:53 am

I had a crack in the head in this area too, where the head screws to the timing chain case. Not easy to see from the outside but oil seeps down from there and along the joint so it looks like the gasket has failed. The alternator was permanently covered in a film of oil until I fixed it!

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PostPost by: KevJ+2 » Mon Jul 17, 2017 9:11 am

The only leak I had in that area was from one of the threads from the chain guide / damper screws. A very small weep but amazing how it collects down there.
I put a dab of araldite over it which cured it.
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PostPost by: prezoom » Mon Jul 17, 2017 3:34 pm

My dip stick tube was a problem leaker. I wound up slipping a thin washer over the stick and made a rubber disc seal between that and the tube. A spring now loops through the finger pull and pulls the stick down tight against the tube. Made a significant difference.
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