over heating engine need help!!!!

[djboots]

I really don't see the connection between the impeller change and no coolant in your block. As far as I know you don't have to touch (or drain) the closed cooling system to change the impellers. I don't doubt for an instant that you didn't have antifreeze in the block but something doesn't sound right here.

Can you talk to the folks who did the service work about why the engine did not have any coolant in it? Did you ask them to change the coolant? I am concerned there may be something else going on here that is not readily apparent if they didn't touch the coolant. Are there any signs of antifreeze in the bilge?

At this point i see no leaks at all....its really weird. I can say that i have never really checked the level before though. I just bought boat last year and used it all season with out a problem. There was always coolant in the overflo tank so i assumed it was fine....I dont know what up:huh:

 

[Dave S]

For your own peace of mind, I would have a Marine Technician perform a pressure test on the cooling system. It won't take long and shouldn't cost much. If it checks out OK then don't worry about it anymore even though there seems to be no reason for the loss of coolant.

If there is an internal leak allowing the coolant to just "disappear" the pressure test will at least give you a clue to start looking at other components. Intercoolers fail as well but I don't have any personal experience with them. I would think ifan intercooler fails you might see a leak in the bilge. But I suppose depending on the type of failure it could allow the depeletion of antifreeze thru the cooler itself since the antifreeze is under pressure once the engine heats up.

Dave

 

[Jimmy Buoy]

Even if you had an internal leak in the heat exchanger, the antifreeze would not usually dissapear in the blink of an eye. You'd see the level in your resevoir dropping the more you run the engine.

I'm suspecting your tech took off an engine coolant hose by mistake when taking the raw water pump out and forgot to refill the system. You should know pretty fast as you run the boat - just keep an eye on your resevoir level and your temp gauge! You might as well try this as you've refilled the system with coolant.

I had to replace a heat exchanger last year. It can be frustrating since a "cold" pressure test in my case indicated "no leak", but as soon as the system heated up to 160 and the metal expanded - the coolant would leak out to the sea water side of the system. If you still lose coolant, I'd take the exchanger to a rad shop where they can do a proper test for leaks.