have a small coolant leak at the top where the rad hose clamps to the housing for the thermostat/waterpump. it leaks out minimally but i'd like to stop the coolant from getting on the engine block and burning off. i can smell it when i get home from work. what do i use to re seal it? a cork gasket, or just some high temp sealer in a tube. i have both.

thanks.

changed the o-ring on the thermostat as well as gave the outlet a good sand where it sits against the block. seems to have taken care of the leak, thanks for the advice.

If it is leaking between the water outlet and the hose, and tightening the
hose clamp doesn't help, the aluminum water outlet is probably corroded
and should be replaced.

If it is leaking between the water outlet and the head, it may also be corrosion,
or it might be that you just need a new U-seal ring that goes around the edge of
the thermostat. If it still leaks with a new ring, the water outlet lower flange
may be warped. You can lap it flat with some wetordry paper on a flat surface.
Tightening the bolts too tight is the most common cause of warpage and will NOT
stop it from leaking. All the sealing is between the rubber U-ring, the water outlet
and the head, NOT between the flat surface of the water outlet and the head.
Thus a gasket will not help.
--
George Downs Bartlesville, Heart of the USA!

its leaking between the head and the aluminum outlet, i've tried to tighten it and it helped a bit. i didn't think it needed any gasket but picked one up regardless.when i changer the thermostat & rad on my 220 i replaced the rubber ring and it was fine. the 142 has a new thermostat so i bet the outlet housing is warped, i'll pull a spare off my B18 thats sitting in the garage after i check the rubber ring. thanks for the help.

Not really sure where you are talking about.

The thermostat is at the front top of the head and has a hose connecting to the top of the radiator. The only gasketed joint there is a rubber seal that goes around the thermostat inside it's housing. You should not need cork or high temp sealer to make it watertight.

The water pump is at the front of the block below the head with a hose going to the bottom of the radiator, an o-ring seal at the pipe to the rear of the pump and two o-ring seals at the top of the pump to head surface. The pump has a paper gasket between it and the block, and the o-rings mentioned. Like the thermostat housing, there is no cork or high temp sealer required to make it watertight.

If it is leaking at the hose, maybe a clamp is a little loose or the hose is beginning to crack.
--
Tom - '60 544, '68 220S, '70 145S, '86 745T, '06 Mazda MPV