What you want to do is get a good sealer silicon or any other type and put it on a gasket on the inside. Best gasket sealer for water pump 2020.

The Best Gasket Sealers Review In 2020 Car Bibles
What gasket sealer to use on water pump. Permatex 22071 water pump and thermostat rtv silicone gasket 05 oz 05 ounce. Copper gasket sealant available both in brushable and in aerosol forms copper gasket sealer is fast drying and the metal content suspended within the sealant helps to dissipate heat and promote even heat transfer between the mating surfaces. Highest water glycol resistance available in an rtv silicone. Its been 5 years since i installed my new not rebuilt water pump and no leaks. 2 is great for any bolts that go into watercoolant and need to be sealedbtw. I use permatex hylomar hpf gasket dressing on one side of the gasket only to help hold it in place during installation.
Let it cure a few minutes before assembly and a few hours at least in warm weather before filling the system. Then you put the gasket on a pump. But it is rather tough to remove in the future. I also used it on the thermostat housing and valve covers. Its designed to stay pliable so disassembly is easier. 52 years of experience.
It can also be used to fill small imperfections in the metal surfaces promoting a more positive seal. A thin coat of good silicone rtv is what id use for a gasket. Highest water glycol resistance available in an rtv silicone. J b weld 32507 water pump and thermostat housing rtv. A noncorrosive sensor safe rtv silicone gasket material formulated specifically for water pumps and thermostat housings. Well here our team have listed down top 15 best gasket sealer for water pump of 2020.
Then let it sit for a half an hour or 40 minutes and when it is sort of dry then you can bolt it onto the vehicle. A non corrosive sensor safe rtv silicone gasket material formulated specifically for water pumps and thermostat housings.