I have to replace a Yanmar custom molded seawater coolant hose between the ZF transmission cooler and the seawater pump.
Should I use a sealant with the hose clamps? The existing install has a gray goop sealant the mechanic used. Yanmar dealer said its a Yanmar speciality sealant at $65 per 6 oz tube. Doubt I'll find that here in Mexico.
If the new hose is the correct replacement for that position sealant should not be required, if a sealant is use the hose will try to ''walk'' off the nipple. The old hose may have been on/off a few times stretching the hose hence the need for sealant.
just replaced my main outlet hose - because the old one had hardened it was difficult to seal so with the new one i spread a bit of hylomar on the outlet nipples - drizabone. Might not have been necessary, but certainly a good seal.