Another engine temperature issue

betayv

Senior Chief Petty Officer
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May 13, 2008
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706
Boat is inboard twin mercruiser 5.7 carbureted engines, fresh coolant system both engines one engine shows temp running in the ocean 1500 rpm 165, the other engine 190-200, both engines raw sea water pumps new, both engines not thermostat, hoses been clean of debris or obstruction, the engine running hotter engine oil is clean not milky, any help what else I missing.
 

Bondo

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Apr 17, 2002
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fresh coolant system both engines one engine shows

Ayuh,...... Is this new freshwater systems, on older motors,..??

Have any flow tests been done on the H/E's,..??..??
 

betayv

Senior Chief Petty Officer
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May 13, 2008
Messages
706
Hi mr bondo boat is a 1989, not very sure how old is the fresh water system, flow test can you explain better thanks
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Back flush the raw water line and the PS cooler
 

betayv

Senior Chief Petty Officer
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May 13, 2008
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706
Yes water test been done on the ps cooler and the lines, yes laser gun been used to be sure the temp is accurate.
 

tpenfield

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Jul 18, 2011
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Heat exchanger clogged?
Riser/elbows clogged?
Bravoitis? (Bravo outdrives right?)
Marine growth restriction in the water duct within the outdrive?

I would be thinking a restricted flow on the hot engine.
 

betayv

Senior Chief Petty Officer
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May 13, 2008
Messages
706
Any idea how can I check if the the heat exchanger is clogged, not outdrives this boat use direct drive transmission
 
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