488 mercuiser

[lynnboy021]

i keep adding coolent to the motor and overflow tank but i always need to add more... new head and manifold gaskets...

 

[Eric 3.7LX Alpha 1]

Re: 488 mercuiser

Sounds like it might be a leaking heat exchanger. Coolant mixing with seawater and draining out the drive.

Isolate the coolant lines to the exchanger and rig up a pressure gauge so you can put air pressure to it and see if it holds. (If you take the hoses to a plumbing supply they can set up the fittings and gauge for you).

Keep the air pressure within the rating of the radiator cap which is stamped.

If it leaks you can have a radiator shop repair it.

 

[stonyloam]

Re: 488 mercuiser

A compression check and coolant pressure check is in order. Autozone will loan you the tools for free. Drain a little of the seawater out of the exchanger (aft plug) and see if antifreeze is present. Good luck.