4.3L Volvo heat exchanger is hot to the touch on port engine

jdogonhood

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Jun 26, 2011
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25
I bought a new to me boat this year. 1991 Carver Montego 530. Has been running good. I was doing routine maintenance and afterwards started both motors to warm them up. After a few minutes I accidently bumped into the port side heat exchanger and it was HOT. The starboard side was just slightly warm. After looking a little closer I also noticed coolant was leaking from the cap. The port side temp gage has been running consistently warmer as well but never close to over heating. The exhaust manifolds on both engines were warm to the touch equally but not hot. My question is.....would just a bad cap cause the exchanger to get hot or is something else happening and just hasn't failed yet? Should I just replace both water pumps and the thermostat and cap.....OR?? Thanks in advance for any help!
 

Bondo

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Apr 17, 2002
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Ayuh,.... I'd swap out the impeller, 'n fix the leakin' cap 1st, then go from there if the heat don't come down,....
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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while at it, clean out the debris in the heat exchangers.

being a 91, you will most likely need to replace the little casting that the water inlet hose connects to on the drive side.
 

jdogonhood

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Jun 26, 2011
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25
Thanks guys. Much appreciated. So I don't have a trailer for it. Is there anything I need to know about changing the impeller while it's in the water?
 

dypcdiver

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Nov 1, 2005
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1,016
On my boat when changing the impeller I just raise the inlet hose above the water line and secure it with some string. Usually only leaks a cup full or so into the bilge.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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You can change the impeller while in the water, but the boat needs to be out of the water for bellows service and to get to the inlet casting
 
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