RTV sealant - give us a clue

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cheesebox
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Post Sat Aug 05, 2006 3:52 pm

I'm rebuilding my M42 engine. The Haynes manual mentions using a bit of RTV (room temp. vulcanising silicone sealant I think) on joints between eg timing case and crankcase before fitting the gasket. Not under the entire gasket, just on the points where the separate bits of metal meet.

Does anyone know of a suitable compound? I couldn't find anything in the local parts shop with RTV written on it. The guy said to use Hylomar Blue but I've just been reading a thread on another forum which says do NOT use Hylomar Blue - I think that is for applying to the whole gasket.

Please tell me what to think
ian332isport
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Post Sat Aug 05, 2006 4:01 pm

Pretty much any silicone gasket sealer will do. I don't think the RTV bit is all that important. Even bath sealing silicone would be fine, but you need the proper stuff that stinks of vinegar when it cures. It's fine with heat and actually works very well on exhaust system joints.

I personally use this:

http://proseal.supergluecorp.com/80044.html

Can't remember exactly where I got it, but think it was a local factors.

Ian.
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smithy318i
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Post Sat Aug 05, 2006 4:04 pm

any old clear silicone will do mate. its pretty much all the same stuff.

dont use white or black tho.
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ian332isport
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Post Sat Aug 05, 2006 4:09 pm

smithy318i wrote:dont use white or black tho.
What's wrong with black ?

Pukka BMW stuff is black. Agreed that white would look nasty 8O
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smithy318i
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Post Sat Aug 05, 2006 4:17 pm

black stuff i had started to crack and flake off (same as white)
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ian332isport
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Post Sat Aug 05, 2006 4:18 pm

Mine has been in there for over 4 years and is still dry as a bone :D
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Turbo-Brown
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Post Sat Aug 05, 2006 4:37 pm

Used Hylomar to seal a sump once.

Unfortunately it reacted with the oil and went rock hard and inevitably cracked causing much oil leakage!
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cheesebox
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Post Sat Aug 05, 2006 7:06 pm

Thanks guys, I've got myself some clear silicone sealant now.