Author Topic: Cylinder base gasket 'blown out'.  (Read 2345 times)

Online bikerbob

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Re: Cylinder base gasket 'blown out'.
« Reply #15 on: 25.07. 2011 15:51 »
Hi there
With regard to gasket sealing I have for the past 15 years used household bathroom and kitchen silicone sealer not the sealer for sealing window frames as is not silicone based. I use a minimum amount on each side of the gasket and then tap it all round with my finger this gives it a textured effect then tighten up and I have used the same gasket sometimes up to 3 times without any problems. With cylinder head gaskets I never use anything they go on dry, I always make sure all surfaces are clean and flat beforehand.

Online olev

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Re: Cylinder base gasket 'blown out'.
« Reply #16 on: 26.07. 2011 12:57 »
Gday Adrian,
I think Yamabond is the same as Threebond 1104.
The stuff is brilliant. I'd be amazed if its the cause of your problems.
I use it metal to metal on crankcases and both sides on everything except head gaskets.
it sticks like sh*t to a blanket and its just as hard to get off.
Your idea about the studs sounds more likely.

Online RichardL

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Re: Cylinder base gasket 'blown out'.
« Reply #17 on: 26.07. 2011 15:08 »
May be wrong,  but looks to me like very spotty contact with gasket,  and that the sealer has hardened.  I think that it does not make sense to use metal-to-metal,  machine-fit sealer where a gasket is required. I use permatex #2 on both sides of gaskets to enhance the surety of a seal and to keep the gasket in place. I know that better men than I grease one side,  but I have trouble seeing that as having the same sealing power as the Permatex. There is also no good reason to try to reuse paper gaskets.  They're available an cheap.

Awaiting thrashing,  or,  even,  agreement.

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at for details.

Online chaterlea25

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Re: Cylinder base gasket 'blown out'.
« Reply #18 on: 26.07. 2011 20:06 »
Hi All,
A peculiar problem allright *conf* *conf*
There must have been some pressure in the crankcase OR for some reason the crankcase mouth or cylinder base are not flat???
Clean everything and fit on the barrels without any gasket or sealer, then try with a thin feeler gauge to see if there is a gap between the 2  ????
Or it maybe as T20 says and the studs are a fraction long??

Petrol will dissolve ""bathroom sealer" almost instantly and in my opinion should be left for the bathroom jobs
Its also famous for blocking oilways and causing other problems *eek* *eek*

John O R
1961 Super Rocket
1963 RGS (ongoing)