One of those years were Talisman craps on me. Several issues have arisen so far which luckily I have dealt with. One potentially remains that I can use some help with.
Did all my usual maintenance over the winter and then some. May trip motored for 10+ hrs no problem. Couple of weeks later after less than 1 hour engine overheated. Turned it off looked at strainer which did not have debris. After cooled off turned on again overheated. Anchored overnight, next morning engine fine used it for two hours. Called Hansen Marine they said airlock that worked its way out. No problem leave alone.
Friday ran engine in neutral for an hour, no problem. Saturday morning ran for an hour again fine. Saturday afternoon overheats within 20 minutes. Same routine check strainer no debris, cool, turn on again, overheats. Sunday morning removed hot water heater hose from thermostat housing and raised above engine. Doesn't appear to have a problem. Checked everything, no visual issues. Turned engine onlooking at exhaust. Some debris came out but water flow seemed fine.
So. Could it be debris is getting passed the strainer? I'll check to make sure it seats well in housing.
I'll check it before engine starts in future.
I'm tempted to change the thermostat in case it is defective and only opens sometimes.
Any their suggestions?
Enrique
Talisman
1998 36 MK2 Hull #1673
Tall Rig Wing Keel
M35BC engine
Old Saybrook, CT Summer
South Glastonbury, CT Winter
Is the impeller OK. does it need to be burbed. is there enough fresh water in the engine block. Yes replace the thermostat. Also bypass the water heater coil and see what happens. Collapsed hose. Hose clamp too tight.
Sail La Vie 1999 Catalina 36 MKII, M35B-17031, Coyote Point, San Mateo, CA
About Sail La Vie
In addition to the above, how about pulling out the heat exchanger and back-flushing it, or maybe even overhauling or replacing it. How does the engine zinc (in the heat exchanger) look? Since it appears to be intermittent, I'm wondering if pieces of zinc get randomly lodged in the heat exchanger?
How about the cooling water nipple into the exhaust riser? Could it be clogged or malfunctioning in some way and not cooling the exhaust sometimes? That can be checked with a laser thermal scanner gun (other post I made a few weeks ago). The gun can sometimes be used to narrow down the heat source.
Ben Ethridge
Miami, FL
1984 MK1 Hull# 263
At the time that the engine overheats, have you checked that water out of the exhaust? Does it look normal?
Nick Caballero
Retired C36/375IA Mk II Technical Editor
Thanks for all the great advice. As part of winter maintenance Impeller in new, zinc is new, H/E tubes were cleaned out. With a RIB on a stern carrier it was tough to see flow but I heard a gurgle when it happened. We did check flow Sunday morning but by then all was fine.
i have ordered a replacement thermostat and a different cover with a bleeding petcock so it will be easier to bleed the system. I intend to check the strainer and make sure it is clear and the screen fits properly. I will do a visual check of hoses and see what happens. If it happens again I'll try to get under stern to check water flow when it does. I'll report back when I'm confident it is fixed. I noticed a rust stain on the top of my muffler box where the hose comes out of. Wonder what that's about. I replaced it all 3-4 years ago.
Enrique
Talisman
1998 36 MK2 Hull #1673
Tall Rig Wing Keel
M35BC engine
Old Saybrook, CT Summer
South Glastonbury, CT Winter
One more thing to check-do you have an Oberdorfer pump? If so, pull the front plate and feel with your fingernail if the impeller has worn even the slightest depression. Flip the plate to the other side and try the new side.
I had a similar intermittent overheat issue with our C30. Pulled everything apart (heat exchanger, strainer, hoses, exhaust elbow, thermostat etc.) Changed thermostat and impeller and the problem persisted intermittently for two years. I finally noticed some wear on the pump face plate. I don't think it was more than .001 inches. I reversed the plate and problem was solved. It takes only the slightest wear to create a suction issue.
The Sherwood pump also has a face plate. I would check that for wear if you still are using that pump.
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B
Forgot to finalize this thread.
the problem was a defective thermostat. Changed it. No more problems
Enrique
Talisman
1998 36 MK2 Hull #1673
Tall Rig Wing Keel
M35BC engine
Old Saybrook, CT Summer
South Glastonbury, CT Winter