My engine coolant reservoir is in the port cockpit locker. It seems I have to fill in with a cup or two of coolant 2 or three times a year as the level drops to the add mark on the reservoir. I have never been able to find a leak around the engine, but it must it is a slow one and may not be easy to find.
Anyone else noticing a slow drop in coolant during the year?
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Ken Enstrom
2004 C-36 MKII #2199
Tall Rig, Wing Keel, M-35B
S/V Valkyrie - Sail Great Lakes
Ken, every year you need to go over all of the hose clamp connections with a hefty screwdriver and socket wrench. Chances are that this will solve your coolant system's slow leak problem.
Larry Brandt
S/V High Flight #2109
Pacific Northwest, PDX-based
2002 C-36 mkII SR/FK M35B
Thanks, I can tighten all the hose clamps in the engine area, but do you know if there are clamps I need to get to between the cockpit locker and the engine area?
Ken Enstrom
2004 C-36 MKII #2199
Tall Rig, Wing Keel, M-35B
S/V Valkyrie - Sail Great Lakes
I have the same problem with our 2005 C 36 we just purchased and found many clamps that were loose. Two were loose enough to allow antifreeze to escape. I tested by applying a dry paper towel to the hose ends to see if it picked up any dampness, as well as run the engine in the cool weather with a flashlight beam to pick up any steam. I've stopped most leaks, but not all, so the effort continues beyond the engine compartment. Obviously, if you run the engine while looking for leaks, keep your hands away from the fan belt.
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B
Don't forget the hot water heater, its connections and the guts. Don't know how old your heater is. I recently replaced our 16 year old heater, captured the coolant, all was well. Until the hose from the coolant engine pump to the HX chafed through...
You have to look on YOUR boat, 'cuz no one here knows what anyone else could have done.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
What about pressure testing the coolant system?
Do you pressure test from the coolant resovoir or rhe radiator cap?
The coolant resovoir cap looks like it will not hold a seal with normal coolant pressure testers.
Seems it would be safer than working around hot engine and moving finger bitters!
Two other places to loose coolant without a trace is the heat exchanger - either endplates or tubes to raw water and the exhaust manifold to riser gasket. My slow leak was exhaust to riser a new gasket fixed the problem.
Les
Les & Trish Troyer
Mahalo
Everett, WA
1983 C-36 Hull #0094
C-36 MK 1 Technical Editor.
Commodore
You want to pressure test at the cap on the heat exchanger. I use a Stant tester with the engine off.
Chuck Lennox
97 MKii Ventura Ca
Island Girl Hull #1611
The last small leak I found was from an unusual source, but others may also have the same issue. On the hose nipple at the back of the exhaust mainfold/antifreeze resevoir, there was a metal burr left over from the manifold casting process. The burr distorted the hose and made it impossible to obtain a thorough hose-to-nipple seal regardless of how tight the hose clamp was. I had to remove the burr by grinding it. I also had to replace the hose. This aggravating minor leak took a few weeks to track down.
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B