Logo

4.236 Initial Overheat - Plumbing ?

Maxxx

New member
Ever since we had the boat, the engine will briefly overheat if it is not left to idle for a very long time. Once it is brought down to temperature it will not overheat again even if you drive around at WOT.

Thought it was a sticky thermostat but that tested fine.

All the usual things have been checked or overhauled: heat exchanger, exhaust elbow, raw water pump. Tons of water flow out the exhaust.

Confirmed it is not an indication issue but checking with an handheld heat sensor.

One thing I did notice is that the plumbing for the hot water heater is different from another 4.236 I saw. Both sides are plumbed off close to the thermostat. How are they plumbed in on other boats ?

Thanks,

Max
 
Sounds very similar to my Perkins 4236. I'm not clear what you mean by " if not left to idle..." My engine temp guage goes up to 210 or so and then after several seconds drops very quickely to 180...as if the thermostat was just opening. But, I've installed a new thermostat after checking both the new and old. Both opened at 180.

I'd sure like to hear if you get some suggestions.

JimZ
 
Sounds very similar to my Perkins 4236. I'm not clear what you mean by " if not left to idle..." My engine temp guage goes up to 210 or so and then after several seconds drops very quickely to 180...as if the thermostat was just opening. But, I've installed a new thermostat after checking both the new and old. Both opened at 180.

I'd sure like to hear if you get some suggestions.

JimZ

It appears that drilling a 1/16" hole in the thermostat sorted the issue. I can't make it overheat now. Full details at: http://www.cruisersforum.com/forums/f54/4-236-initial-overheat-plumbing-114822.html
 
Back
Top