Gasket Advice

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TGNelson
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Post Fri Jul 10, 2020 9:50 am

I'm planning on replacing the rocker and sump gaskets as I have a small leak coming from those locations. I've seen a lot of contradicting advice as to what type of gaskets to use. Some people suggest cork for the sump, others paper. Also, some places suggest using a loctite sealant first but others say this is the worst thing you can do.

I'm just wondering what methods and types of gaskets have you guys used for this and would recommend? Also, do you recommend replacing all the bolts and nuts while I'm there or could that introduce a new issue?

Cheers
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flybynite
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Post Fri Jul 10, 2020 10:11 am

Bolts for small things like that are fine, I only replace if damaged.

Gaskets, I use whatever Elring put in the pack, just looking at one I have on the shelf it is a fibre material for the rocker and cork for the sump. Never used anything else and had no problems to date.

Paper only works on well-fitting faces, sump and rocker need something more forgiving.

Loctite is a manufacturer and not a product. They make some things that are approved for gasket replacement and some that will either not seal at all or mean you won't get the rocker/sump off again with anything less than a 9" angle grinder. Which is where some of the problems you read come from!

Just make sure both surfaces are clean (including the bolt holes) and don't over-tighten.
TGNelson
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Post Fri Jul 10, 2020 10:46 am

Sounds good, I'll go with Elring and use what they give. For cleaning the surfaces, I've seen it done with both a metal razor and a plastic one. Is this because the metal could damage it or as its more forgiving will a metal razor be fine as long as I'm careful and get a good seal otherwise?
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flybynite
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Post Fri Jul 10, 2020 10:57 am

I use metal scraper to get worst off and scotchbrite pad or wet-and-dry to finish off
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Brianmoooore
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Post Fri Jul 10, 2020 11:26 am

flybynite wrote:
Fri Jul 10, 2020 10:11 am
and don't over-tighten.
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Ukhozi
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Post Fri Jul 10, 2020 11:45 am

flybynite wrote:
Fri Jul 10, 2020 10:57 am
I use metal scraper to get worst off and scotchbrite pad or wet-and-dry to finish off
Ditto, Spatula and then scotchbrite pad. Just don't 'dig', keep it flat and level.
Everyone has the right to reach the level of their own incompetence.
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HJ1981
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Post Mon Jul 13, 2020 8:20 am

I replaced the sump gasket twice and it still leaks, both times used the cork gasket and no sealant.

AJUSA brand sump gaskets are paper, which are more forgiving when using sealant, i shall be going down that route next oil change.

Scotch Brite pads are amazing, the only thing out there that would clean any mating surface without scratching.
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jmec
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Post Tue Jul 28, 2020 9:29 pm

Hylomar is a good gasket sealant if you're using a paper gasket. I've been using it for industrial applications for many years.
JungleGus
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Post Tue Jul 28, 2020 10:17 pm

I find making sure everything (bolts and gasket surfaces) goes a long long way to making sure gaskets seal right.

The problem with adding gasket sealant is that it's possible to add too much and have clumps come out into the oil supply system - not ideal. A thin bead only in the centre usually is fine (a lot of gaskets come with it pre-impregnated in a dry form). TBH have never had any issue using the BMW gaskets and no sealant