Sailboat engines are why I drink

[Uno Mast]

I noticed that after sitting for a few weeks, my antifreeze had all drained into the bilge, I thought at least. Here's the deal, The bilge had a ton of antifreeze, the AF (antifreeze) tank was empty, I filled the AF and it drained right away, I filled it again to see where it was draining, couldn't find it. I filled it again and all the sudden, no more draining. So, time to start the engine, we left it running for approx. 5-10 minutes, all seemed just fine. Went down to check the AF and it's empty. I know I need to do some more checking tomorrow with a clean bilge but, any ideas??

A tiny bit of back story...the engine was overheating almost every use for 2 years, finally we found that it was due to a clog right next to the thermostat. It ran fine for a lengthy test of running the engine and for an all day sail using the engine intermittently. On the all day sail we hit bottom, got stuck and I ran the engine in full or almost full power in reverse to get unstuck.

Thanks for any thoughts.

Matt

 

[Pat4324]

It's possible you have an internal leak in your heat exchanger. If that's the case, your antifreeze would mix with raw water and get expelled out thru the exhaust. I had this happen on my engine. It may be hard to see the antifreeze in the exhaust stream, but if you inspect the inside of your lift can, you would be able to smell the presence of antifreeze.

 

[Davidasailor26]

When you refilled it, I presume that was into the overflow tank? I'm guessing that you have a leak from the block, pump, tubing, or HX that's draining into the bilge. The first time you refilled the overflow tank it drained immediately into the empty block/HX. The leak must be slow enough that the block was still full (ish) so the second batch you added didn't need to drain back into the block. Then in the time that you ran the engine it all drained into the bilge again and sucked the excess out of the overflow tank.

 

[Uno Mast]

Thanks for the input fellas. We'll put that into consideration.
Cheers