JOHN R.316
Member
I went down to check on boat this past Sat. Found that stardboard heat exchanger lost antifreeze. Port side full. where is it going? Is heat exchanger leaking? Boat is in winter storage. 454 mercruser.
Heat exchanger loosing antifreeze
- Thread starter JOHN R.316
- Start date
- Nov 26, 2006
- 7,628
- Boat Info
- 2008 44 Sedan Bridge
- Engines
- Cummins QSC-500's
Straight Drives
I noticed that no one answered your post. I just recently learned that if your heat exchanger is failing, the antifreeze will leak out to the sea water due to higher pressure inside the antifreeze side. While sitting in storage, I would imagine that it would still go that direction due to the fluid level of the AF being higher than the heat exchanger. So, from there, it would go out of the exaust.
The problem is that the AF is being diluted by residual water in the exhaust so it may be very difficult to detect. I would make sure it's not dripping into the bilge first, then check the exhaust fluid for signs of AF. Good luck. If you find fluid dripping from the exhaust, or dampness around the exhaust, pink color or a sweet taste would be signs that your heat exchanger has failed and needs to be replaced. The ones that fit my engines cost $800. B O A T housand - hopefully not. Maybe just loose hoses.
Frank informed me that its common for hoses to loosen up - especially during cool weather. Check for leaks.
The problem is that the AF is being diluted by residual water in the exhaust so it may be very difficult to detect. I would make sure it's not dripping into the bilge first, then check the exhaust fluid for signs of AF. Good luck. If you find fluid dripping from the exhaust, or dampness around the exhaust, pink color or a sweet taste would be signs that your heat exchanger has failed and needs to be replaced. The ones that fit my engines cost $800. B O A T housand - hopefully not. Maybe just loose hoses.
Frank informed me that its common for hoses to loosen up - especially during cool weather. Check for leaks.
JOHN R.316
Member
Thanks for the respons. I will go down to the boat as soon as weather breaks, early March. Plan on removing Heat exchanger bring home check it for leak.
Last edited:
Nehalennia
Well-Known Member
- Aug 22, 2007
- 10,006
- Boat Info
- 2001 310DA twin 350 MAGs, Westerbeke 4.5KW
- Engines
- Twin 350 MAG V-drives
Also, check your oil and make sure it is not milky looking, which is a sign of head gasket leaking or allowing fluid through.
Best of Luck
Best of Luck
47etep
New Member
I had the same problem, turned out one manifold had pinholes into the exhaust chamber letting AF into the cylinders- Bad news. One good way to check where the problem is is to isolate each section of the system by disconnecting water hoses and pumping in 15psi of air. The hoses are the size of 3/4 inch iron pipe making the various plugs and fittings required easy to fabricate.
