I'm replacing the crank seals on a 435 and using new rubber cylinder base gaskets as well. Should I use any RTV/sealant/grease or just put the gaskets and seals in as they are?
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fleethirte
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take out base gasket and just use three bond!
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Its a clamshell- uses a couple of small rubber seals in the rebates of the cylinder pan and should also have a smear of liquid gasket (should have been evident when pulled apart?) on all contact parts.
As a rule- standard RTV silicone has no place in the chainsaw workshop- use one of the trusted liquid gasket making offerings- like Yamabond, Hondabond, Three Bond (as suggested above), Permatex, Dirko or whatever one you can find.
As a rule- standard RTV silicone has no place in the chainsaw workshop- use one of the trusted liquid gasket making offerings- like Yamabond, Hondabond, Three Bond (as suggested above), Permatex, Dirko or whatever one you can find.
There was no sealant of any type on there when I took it apart. I saw another thread about this type of gasket where people suggested just using a light coat of grease. So that's what I did. Tested after assembly and it holds pressure and vacuum, so hopefully it stays that way!
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Why? There was no sealant or gasket maker on there from the factory. I put it back together the same way. Could I have added something for extra insurance? Sure. But I thought I'd give it a go as it was originally done.
seen some pretty bad information on some youtube wanabe's but also there is a lot of good info out there - ya just have to know the difference
huskydave
Addicted to ArboristSite
I would just use the gasket, you could ditch the gasket and use just permatex black RTV but then you would have to check your squish band because this would bump up compression and you would have less clearance between the combustion chamber and the piston. To do this you need a long piece of solder, stick that through the spark plug hole and pull the saw over slowly, remove solder and measure, you don't want anything less then about 20 thou clearance and you should run premium fuel if you do that.
Tomos770
ArboristSite Guru
DIY....
Yeah he used just some oil on the rubber gasket - similar to the light coat of grease that I did.
Welp.... by golly the service manual does not say anything aboot using any sealant. I stand corrected.
However... in my and maybe others experience, always use a thin layer of some kind of high temp sealant. Especially at the corners of seals and mounting points of all clamshell design small engines. Even around the OD of some crank seals.
However... in my and maybe others experience, always use a thin layer of some kind of high temp sealant. Especially at the corners of seals and mounting points of all clamshell design small engines. Even around the OD of some crank seals.
