Hitchcocks Forum

Hi all. I think I know the answer to this already, because I've read it in lots of different places.

Is is really OK to use silicone bathroom sealant to make the exhaust port/pipe connection airtight? Doesn't it get too hot around there? Is the sealant OK at these temperatures?

Thanks

Ed

In short, yes, no, yes.
I have been using it for years with no problem whatsoever, just leave it to dry 24hrs before starting engine.

Like wise I Have had No Problems at all using Cheep Industrial Sealant (Everbuild I think) in any Motorcycle use!

What did Surprise me on the exhaust is that it stayed Soft But firm Years Later (Put Plenty on Cut off excess a Month Latter, OH and Clear Looks Better than White ;0)

Ok On gaskets & Primary too....

It really does work; I have done it and no problem at all. It still seems like it would melt if you think about it. But... it doesn't.
Regards, Chris

It really does work; I have done it and no problem at all. It still seems like it would melt if you think about it. But... it doesn't.
Regards, Chris

I had a hole in the silencer of my car just before going away on a trip; no time to get a new box, so I attempted a bodge with a square cut from a coke tin and a dollop of bathroom sealant..... now 4 mot's later, and it is still holding strong!
Wonderful stuff in the right place, just don't get it mixed up with the silicone lubricant in the bathroom cupboard, otherwise: Best case scenario: exhaust falls off. Worst case: doesn't bear thinking about....!

Thanks all. I am reassured.

Make sure it is clear Silicone, NOT a caulk type. The Granville one from Halfords is ideal as some are very acidic. Also useful for general sealing uses.

Hi ed ---------- well, just to upset the apple-cart a little----I changed my pipe last week and, as per usual cleaned out the exhaust port, put a large "Dollop" (getting technical now) around the end of the pipe and a similar amount into the port edges. Push the pipe fully home and tighten the securing nut on the pipe's bracket. Leave any excess for now. Push the cooling finned ring firm against the cyl. head and clamp tight. Now remove any excess with a damp cloth. Have a cup of tea or coffee (plus chokky bikky)--go back and start eng.----leave it for 10 mins or so on idling. Job done. Mine is WHITE and Acrylic and I get the tubes from car boot sales at 50p a go !! Have just come back from a run to Leominster via the hills (120 miles) and absolutely NO leaks, backfire on over run etc and it looks ok. ----------- but got DRENCHED !!! with hailstones the size of your thumbnail.

As I understand it, this stuff cures by absorbing tiny amount of moisture from atmosphere, so maybe best to let it cure cold before starting engine and risking blowing any out before it cures??