1986 OMC Cobra 5.0 thermostat housing

ewpilot

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First post and long time viewer.
Always seemed to find the answers on prior thread. I have been trouble shooting an overheating problem on my OMC Cobra.
I replaced raw water pump....needed it, engine driven pump, checked flow to the raw water pump which was good and back from the engine out to the pump also good.
I have good flow to the exhaust manifolds and see good water flow leaving the exhaust bellows.
I pulled the Thermostat housing and am ready to replace the thermostat.
HERES THE QUESTION. While inspecting the housing I noticed that in the raw water inlet passage....while looking in the large water port... below the thermostat is a hole.

Is there supposed to be a bypass inlet to the engine below the thermostat or has my housing rusted out?
 

ewpilot

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Re: 1986 OMC Cobra 5.0 thermostat housing

ewpilot

heres the link. the hole or port is hard to see but it is there in the water neck
Thanks for the help
It was only getting hot at high rpm settings. I dont know if it would matter if I used it as is.....at least for fireworks today

Happy 4th
 

ewpilot

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Jun 30, 2011
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Re: 1986 OMC Cobra 5.0 thermostat housing

Ran out of time and put it on with new thermostat. Back in the water and ran all night at 180. One thing fixed.....and a few more new issues to go.
 
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