Loosing coolant

[4 winds]

I got the boat out of storage today.Checked coolant tank Empty.I put 6litres of coolant in.I have had this boat for 5 years never had a problem.It is 1987 470.Started engine on the muffs ran great.Checked coolant level tank was full.Took the boat to the water started engine .I noticed a little green in the water.Left dock ran for 5 minutes the heat guage started to rise.I shut the engine off.Looked in the coolant tank it was empty.So i filled the tank up with water. started the engine it ran great but the temperature stays really low.Ran the boat for a hour.Docked boat for half hour.Checked the tank it was low again.It seems to be leaking out the exhaust side when the engine is shut off.Could my exchanger have a crack in it and is leaking out the exhaust when thengine is shut off.

 

[Bondo]

Re: Loosing coolant

Could my exchanger have a crack in it

Ayuh,.... Entirely Possible...

 

[MikDee]

Re: Loosing coolant

I would check the exhaust elbow for cracks, I seem to remember something about these having a problem on this engine.

 

[Don S]

Re: Loosing coolant

Also check your oil level and see if it's milky.

 

[MikDee]

Re: Loosing coolant

These engines have a Lincoln head, and a mercruiser block, and I think the head is cast iron, & the block is aluminum, or vice versa? (I can't remember which now?) either way, you have a different co-efficient of expansion, so after awhile the head gasket goes bad. I think thats why Don has asked you to check your oil for antifreeze.