Changing Coolant ON FWC

[bbrnhart]

What is the best procedure for changing the coolant? Motor is 92' 4.3L V6 Merc. Is there a perfect drain point?

 

[Don S]

Re: Changing Coolant ON FWC

Level engine. Remove the block drains, pull the hose from the engine circulation pump. This will drain the heat exchanger and the pump. Refill with a 50/50 mix of regular green antifreeze.

If you have a full cooling system (including manifolds) drain them too before refilling.

Run engine on muffs and make sure you have no air bubbles in the system.

 

[bbrnhart]

Re: Changing Coolant ON FWC

Boat is in the water but I can pump the bilge out into a bucket. Do you have a diagram of the drain plug locations?

Thanks

 

[Don S]

Re: Changing Coolant ON FWC

Look at the sides of the block. There is only one plug on each side of the block. Then look at the engine circulation pump. Only one big hose going to it from the heat exchanger.

 

[bbrnhart]

Re: Changing Coolant ON FWC

OK thanks