Found Antifreeze under my engine

[Davidasailor26]

I had a similar experience. The first winter we had our boat I noticed a few tablespoons of antifreeze under the engine. Never saw anything during the previous summer. I traced the leak to one of the hoses where it met the thermostat. I tightened up a few hose clamps on the hoses around there and haven’t had any problems since.

 

[thinwater]

Sometimes systems leak because the elastomers stiffen and contract in the cold, making for hose and gasket leaks. Common. Better clamps help. Some truckers swear by spring-tensioned clamps rather than screw clamps. Google "cold flow coolant." Really, this is a trivial problem that probably does not need to be fixed. Finding the problem in warm weather can be very difficult.

 

[Tally Ho]

I had a leak on my 2GM20F Yanmar. I checked and tightened every hose clamp I could find on the engine. I also made sure my overflow tank was properly filled…. And no more leak. I never knew which hose clamp was the culprit, but a few were loose enough to take a 1/4 turn.

Greg

 

[Scott T-Bird]

I found a bit of leakage underneath the overfill tank this spring. I don't think that little rubber hose is even clamped at the plastic cap. Or if it is, it is one of those tiny spring clamps that you have to squeeze with your finger tips. I don't think it is uncommon. I don't always notice any leakage but I know that i have experienced it in the past. It's really not even a nuisance. Wipe it up in the spring and that's that. I think that it doesn't always occur because we have numerous winters down by the shore where we really don't have any cold temps for the winter. But this winter was different. We had a long stretch of very cold weather and lots of snow. Barnegat Bay actually froze over this winter ... very rare.

I haven't thought about it before but I don't understand how the contents of the bottle could leak. I'm thinking that there is antifreeze in the hose that doesn't drain because the hose is basically level from the heat exchange cap to the overfill cap and the fluid leaks out at the overfill cap only in very cold temps because it is very loosely clamped (if at all).

 

[sailcapt340]

Scott, Me too….I checked the bottle and found no signs of cracks or seepage. I went as far as to take it home and pressurize it with a small compressor I have and it doesn’t leak. You’re right it’s really just a nuisance, but I just had to ask. You don’t know of you don’t ask right.
And I am surprised others have had this going on as well.
My hose from the overflow is not clamped and never has been.
What really puzzles me, is that I can find no signs that a coolant would leave on any surfaces anywhere.
It‘s like someone actually poured the antifreeze under the engine.
And yes we had had very severe winter here as well, record setting snow falls and cold.
I plan to watch this more closely going forward.