Both KAD32 engines running hot.

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Gavla

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Hi, i have just carried out a sea trial on a sealine f33 1999, with twin kad 32's. On the sea trial i found after about 15 mins both engines had a temperature of around 110c whilst revving at around 3500 rpm. The engines have covered 478 hrs and look very clean. They haven't done alot with the previous owner, he has barely used the boat in the 3 years he has owned it. Has any one got any ideas why these engines are running this hot?
Im thinking it could be due to lack of servicing as the impellers haven't been changed out on quite a while is my suspicion.
Thanks Gavin
 
Impellers, exhaust elbows corroded, outdrive intakes partially blocked, seacocks partial blocked, cooling system needs cleaning, leak on suction side drawing air, strainers blocked, gauges wrong to name but a few!

Take your pick! ?
 
FARSCO said:
Impellers, exhaust elbows corroded, outdrive intakes partially blocked, seacocks partial blocked, cooling system needs cleaning, leak on suction side drawing air, strainers blocked, gauges wrong to name but a few!

Take your pick! ?
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Thanks FARSCO, looks like it might be a walk away from this one then. I had to rebuild the engine on my last boat as it was down on 3 cylinders. Done it all with a friend of mine so didn't cost the earth. its just a case of weather i take a punt on this boat, and it being something simple like replacing the impellers.
 
DrSpock said:
Quite possibly needs the heat exchangers de-calcifying. Not a big job by any means.
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No, but chasing an overheat problem can be labour intensive starting at weight, props, drive intake, entire raw water cooling system, coolant system (pump, sludge caused by mismatched coolant etc), turbos, fuel, injection. The works. As Farsco says. Take your pick because sods law is quite clear on the matter. It's never going to be simple or what you first think.
 
If the boat was otherwise smart, I would consider either asking the seller to fix the issues and ping back when ready for another sea trial, or drop your offer accordingly to take account of the fact that you could easily run up a couple of K in bills fixing it.

(It could be something really simple such as impellers / strainers / fouled intake, but you have no way of knowing)
 
BruceK said:
No, but chasing an overheat problem can be labour intensive starting at weight, props, drive intake, entire raw water cooling system, coolant system (pump, sludge caused by mismatched coolant etc), turbos, fuel, injection. The works. As Farsco says. Take your pick because sods law is quite clear on the matter. It's never going to be simple or what you first think.
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Weight / props etc are highly unlikely if the boat is original spec. Given both engines show the same symptoms then injection / turbos etc can be discounted, Most likely due to lack of use could mean raw water intakes partially blocked, sea strainers, impellers, calcification etc. None of which are particularly difficult to fix.
 
isn't 110C a temp that you may get other issues afterwards (burnt gaskets, warped heads etc)? I'm only asking, don't know these engines at all
and all that assuming OP checked with an IR thermometer and it's not the gauges (unlikely though)

V.
 
DrSpock said:
Weight / props etc are highly unlikely if the boat is original spec. Given both engines show the same symptoms then injection / turbos etc can be discounted, Most likely due to lack of use could mean raw water intakes partially blocked, sea strainers, impellers, calcification etc. None of which are particularly difficult to fix.
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True, I'm worried about Sods Law though and would not look at the boat again until the issue is fixed. I disagree re turbos though. Lack of use and the exhaust design could well find them rusted up and seized.
 
For what its worth....and, has already been said, take ya pick on what it could be...my KAD32 had an overheat problem and after doing just about everything it was tiny stones wedged inside the oil cooler restricting flow.
On another occasion the impeller lost a few fins= overheat. New impeller fitted still overheating. Bits of old impeller blocking the pick up pipe!
Oh and the shaft on fresh water pump snapped last year.....which is a known problem so Volvo take your old unit and send you a recon ...for loadsa cash!
 
110 , no alarm ? I’d say it’s an electrical problem giving false resistance to the gauge , it would have pushed coolant out at that temp .
kad 32 a good simple motor so don’t dismiss the boat if it’s right elsewhere.

Get the vendor to investigate the fault .
 
FARSCO said:
Impellers, exhaust elbows corroded, outdrive intakes partially blocked, seacocks partial blocked, cooling system needs cleaning, leak on suction side drawing air, strainers blocked, gauges wrong to name but a few!

Take your pick! ?
Click to expand...

Definitely not seacocks.
 
BruceK said:
True, I'm worried about Sods Law though and would not look at the boat again until the issue is fixed. I disagree re turbos though. Lack of use and the exhaust design could well find them rusted up and seized.
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You wouldn't hit WoT if the turbos were seized - I doubt the boat would even get on plane.
 
DrSpock said:
You wouldn't hit WoT if the turbos were seized - I doubt the boat would even get on plane.
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When I got my boat it would hit max rpm and plane without root chargers or turbos. C3 props instead of C4's. Dont always look at things at face value. We dont know what the OP's speed was at 3500 which is not max rpm even though it is WOT. My boat is planing before the turbos kick in as well, that's the function of the root chargers more than turbos
 
Even so I still discount that diagnosis. The supercharger clutch would have disconnected way before 3500rpm and with no turbo spooling you'd immediately feel drag. Anyone who has run a KAD will know the difference between the compressor and turbo running. A seized turbo in additionia parasitic so performance would really suffer - and likely noticeable with a dirty exhaust - let alone the sound (or lack of it) - Ockham's razor.
 
Both suggest a common issue .So rare both turbos , or both spray rings , or both impellers have lost vines simultaneously.
I had the loom resistance = faulty reading gauge + no alarm with one of the pair KAD 300s .
lack of use points to clogged cooling system which has been mentioned.

Did you use a IR thermometer on the stat housing to find the real temps ?
 
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