Scooterotica

Do people use sealer on the joint between downpipe and cylinder or does it get too hot?

never use a sealant- relied on the copper gasket and properly tightened nuts

Chris

I've always used a heat resistant silicone sealant with copper gasket so a bit belt and braces. Don't need to use a lot, just a smear on each side.

Never had a gasket go since using it.

Also, I always recheck the tightness of the nuts after taking it for it's first run due to expansion / heating / cooling cycle of the cylinder, studs, nuts and gasket.

Donnie wrote:I've always used a heat resistant silicone sealant with copper gasket so a bit belt and braces. Don't need to use a lot, just a smear on each side.

Never had a gasket go since using it.

Also, I always recheck the tightness of the nuts after taking it for it's first run due to expansion / heating / cooling cycle of the cylinder, studs, nuts and gasket.

^all whs

byron wrote:

Donnie wrote:I've always used a heat resistant silicone sealant with copper gasket so a bit belt and braces. Don't need to use a lot, just a smear on each side.

Never had a gasket go since using it.

Also, I always recheck the tightness of the nuts after taking it for it's first run due to expansion / heating / cooling cycle of the cylinder, studs, nuts and gasket.

^all whs

+1
Why bother going belt and braces with the head and base and inlet and then not bother with the exhaust?
The slip joint connections on any exhaust should be sealed as well in my opinion.
You'll need a high temp sealer which can be hard to find.
Cam lam do a good one.

How hot does the Cylinder / downpipe join get? Most sealers are only good for 250 degrees Centigrade and I'd have thought that burning exhaust gases were hotter than that.

Hi
Yes the gases are hotter but the pipe or barrell does not get as hot as the gases. That's why when you get an EGT reading of 560 degrees celsius, your cylinder, head and exhaust is not melting because the metal is not that hot just the gas.
The sealer i use goes up to 232 degrees celsius and is more than adequate.
Hope this helps.

nelson pk wrote:

byron wrote:

Donnie wrote:I've always used a heat resistant silicone sealant with copper gasket so a bit belt and braces. Don't need to use a lot, just a smear on each side.

Never had a gasket go since using it.

Also, I always recheck the tightness of the nuts after taking it for it's first run due to expansion / heating / cooling cycle of the cylinder, studs, nuts and gasket.

^all whs

+1
Why bother going belt and braces with the head and base and inlet and then not bother with the exhaust?
The slip joint connections on any exhaust should be sealed as well in my opinion.
You'll need a high temp sealer which can be hard to find.
Cam lam do a good one.

+2

I've got a tube of blue Hylomar indoors. That's rated for 250 degrees so I guess that'll do.

I always use basic clear silicon for cylinder head (no gasket), base ally packer (no gasket) and exhaust flange. Also used for exhaust slip joints, not had a problem with it