Coolant leaking from oil pan gasket

[Don100]

Hello this is my first post. I have 1986 Four Winns 170 Mercruiser engine. I recently noticed a small coolant leak from what looked like it was coming from my oil pan gasket at the front left side of the engine. I have not seen any evidence of coolant in my oil. I slightly tighten 3 bolts on the underside of the engine where the leak was from. Once I tighten these the leak all but stopped. My question is how can coolant be leaking from there? Have I now directed the leak to the engine internals?

 

[tpenfield]

Re: Coolant leaking from oil pan gasket

Welcome to iBoats. . . sounds like you have a closed cooling system ??? You may have re-directed the leak as you said. . . . However, with a closed cooling system you are in a better position to perform a cooling system pressure check, which should be able to isolate the leak.

 

[stonyloam]

Re: Coolant leaking from oil pan gasket

The leak is probably not from the pan gasket, it is probably from the weep hole on the lower starboard side of the engine waterpump. Start the engine (on muffs or in the water) and allow it to warm up and watch for antifreeze leaking out. If it is you need new cam seals. PS DO NOT TIGHTEN ANYTHING on the front of the engine. The covers are cast aluminum and can crack if overtightened.

 

[Eric 3.7LX Alpha 1]

Re: Coolant leaking from oil pan gasket

The oil pan only seals out the oil. It does nothing for coolant. It does get disturbed If you have to replace the cam seals though.

Locate the leak and report back. Several of us 470 owners have done the repair..myself and Terry included :facepalm:^^^^

Welcome to the 470 club :facepalm: