Heat Exchanger Plumbing

[TrailerCruiser]

I've taken my exhaust and heat exchange off and now need to reinstall. I'd like to use some sealant on the rubber hoses so the have less chance of leaking. Any recommendation on what sealer should be used?

[jamhass]

Best to NOT use sealant. Clean the fittings well, use good hose clamps and ensure the hose fits properly. Old hoses swell and crack, so reusing them if they show deterioration is not a great idea. Overly tight hoses can often be coaxed into place with a bit of liquid soap or judicious application of heat.

If you feel you must use a sealant, permatex (or similar non-hardening) sealer might be best. True adhesives will make future removal difficult or impossible.

[a64pilot]

Don’t use sealant, ever. It just makes a mess later and makes them real difficult to remove, and then you have to clean the sealant off the fittings.
If needed use a water based lubricant to install, like surgical lube or dishwashing soap works good too.
Surgical line is a polite way of saying KY Jelly and the like, but do not use any kind of petroelum based lube it can soften the rubber and really glue it to the fittings.

[SVHarmonie]

Billions, literally billions, of rubber hoses are installed without sealant, and without leaking. If you have chronic problems with rubber hoses pushed on to metal fittings leaking you have one (or more) of the following issues (in no particular order):

-not tightening hose clamps properly,
-using the wrong type of hose clamp,
-using old, damaged, wrong sized, or wrong type of hose,
-metal fittings that have been gouged, scratched, or otherwise damaged

Adding sealant is a mistake, for all the reasons previous posters have stated, and to the knowledgeable observer immediately flag repairs as amateur.

[Sailmonkey]

Sealant? I normally use silicone lube in hoses I need to remove periodically for maintenance!