Mercruiser 3.0 Lx losing coolant

[parat]

Hello

i have a strange problem with my engine, it is leaking coolant when engine is turned off. There are definatly no external leakage, i have double checked everything.
The strange thing is that Fresh water coolant is ok while driving, but disapear when i stop. A little while after engine is stopped it slowly starts disapering, and if left over night several liters has disapeared ?
Oil is fine, and as i said no external leakage,,so where does water disapear ?

All answers are higly appresiated.

Tom

 

[Bondo]

i have a strange problem with my engine, it is leaking coolant when engine is turned off. There are definatly no external leakage, i have double checked everything.

Ayuh,...... Welcome Aboard,...... Yer sayin' ya got freshwater closed coolin' on yer 3.0l Merc,..?? With a heat exchanger,..??

My guess is, it's leakin' out into the raw water side, in the exchanger,....

 

[Eric 3.7LX Alpha 1]

I don't have a 3.0 but do have 3.7.. with closed cooling and when the coolant runs low it is either going in the oil or leaking in the heat exchanger out the drive where the seawater comes in from...

Test your heat exchanger for any leaks using a pressure tester with a pressure gauge and air. or bring it into a radiator shop to test it for you...

 

[stonyloam]

If it is not in the oil, not in the cylinders and not in the bilge, yeah I am with bondo and Eric. Leaking into the raw water of the exchanger. If you can, pull the end caps off of the exchanger see if any antifreeze leaks out. Should be only raw water circulating through the tubes.