Overheating KAD32's

jparham

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Overheating KAD32\'s

Hi, has anyone else seen this?
2001 Sealine F33 Serviced annually.
Boat fully loaded (7 adults) at 3,500 rpm BOTH engines overheat to 105degC (alarms at 100degC)
2 POB up to 95DegC no alarms
Have flushed out intercoolers & exchangers with animal eating/calcium eating acid. Intercooler was pretty clean though. Didn't make any difference.
I heard that coolant strength may make a difference - Success! Run 1 engine 100% water, only gets to 90degC! Looks like % coolant makes a 5-15 deg difference in running temp. I've now 'watered down' coolant to minimum in Volvo Spec of 40% and no more problems /forums/images/graemlins/smile.gif
 
Re: Overheating KAD32\'s

Well bugger me! Not come accross that one before.
Thanks for the tip and well diagnosed. /forums/images/graemlins/cool.gif
 
Re: Overheating KAD32\'s

I agree with Kawasaki I have never heard of this before. I assume you checked the impellors before cleaning the system - just interested because one of my KAD32's is running hot when I am at WOT, at any other throttle position its OK, and before anyone asks it's not the stbd engine with the power steering oil cooler. I await the reply from Spannerman.
 
Re: Overheating KAD32\'s

Yes peanuts, impellers replaced and rubber greased at the same service. Checked when things got hot and both were working perfectly.
 
Re: Overheating KAD32\'s

Kawasaki

Is that avatar of yours a bike jumping over a boat? Is that what you get up to in your spare time!

MartynK
 
Re: Overheating KAD32\'s

If you did not follow the manf recommended dilution and increased the concentration of ethylene glycol above 60% it actually hurts the engine’s freezing and overheating protection.
 
Re: Overheating KAD32\'s

Composition by No 1 Daughter (Smart arse with an Ology) "Dad I know you used to race Motor Bikes but now your an old fuddy daddy with an old boat I,ll fix you up with an av!" /forums/images/graemlins/tongue.gif
 
Re: Overheating KAD32\'s

Its a new one to me also!. We always use a 50/50 mix of Volvo and water which is more than adequate for our winters. Although they mix it stronger in the north, but then the sea water temp is lower so they have more cooling effect.

Re your KAD 32 what do you call hot, is the alarm going, is it pushing water out of the filler cap.
I guess you have done the basic checks, how old is the engine, as volvos tend to get blocked heat exchangers and oilcoolers with time. Or it could be something as simple as a stuck thermostat or mussels blocking the water intake anywhere between the leg and the seawater pump, I once found a large mussel right up at the inlet to the sea water pump.
 
Re: Overheating KAD32\'s

The engine concerned is 4 years old and I have just got to 700 hrs running. I have done all the basic checks, it only sets the alarm off at WOT, at all other positions it seems OK. It has always be slightly hotter than the stbd engine as that has the hot water tank in the system. I have not got to the water coming out of the filler cap - yet. My plan is to carry on (not at WOT) till the boat is lifted out for 6 weeks in Jan then investigate, but any constructive ideas would be helpful.
 
Re: Overheating KAD32\'s

I have had the same problem in a single engined cruiser, 2 years old with 20+ hours use. Have spent best part of a year trying all sorts of tests, new impeller, head gasket smoke test, all proved negative.
Can troll around the marina all day, no problem, but out in the open water, full power and the buzzer starts to go and the guage is off over the 100 mark. Keep running and soon the water cascades out of the pressure cap and everything is red hot !!
Just cured last month!! Boat out of water, Outdrive removed and the rubber connector that draws 'raw' water through the outdrive into the engine has been 'crimped' from new.
Replaced this and all is now well, just wasted a whole season of summer boating, having spent most of the time with my head stuck under the engine hatch on a caravan on water.
Thanks go to Mick West in Brighton Marina for diagnosis and cure at a very reasonable £600 including lift and scrub !
 
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