engine overheating

[mike.l]

HI friend brought his 1989 force 50 #507k9b to me he has had problems with this boat for a long time. Been in storage for 10 years he gave up on it, I did a service on it changed oil water pump impeller etc cleaned carb . On muffs it spits a small amount of water out the spit holes put it in the lake it goes well but after 15 minuites the alarm went off and overheat .
Where is the thermostat mounted on this engine also is there a free download manual somewhere on this site i could use. Hoping you guys can help me solve this problem
mike

 

[Nordin]

The thermostat is under the small cover just above the top spark plug.
Be really careful when removing the screws, they can snap very easy.
When you changed the impeller was all fins on the old impeller?
If not check for part of the fins in the water jackets.
Has the engine been running in salt water?
If it has the water jacket might be clogged by alloy corrosion.

 

[mike.l]

thanks i will check it out never in salt and impeller was all intact but found out from the owner a local marine put one in backwards for him so do not know where those parts went

 

[jerryjerry05]

IF??? it sat for 10 years?? it's possible the wasps and other mud bugs have clogged the system.

 

[mike.l]

Hi that is a big possibility i found the thermostat was wide open and the gasket was out of position tried to flush it with hose pipe backwards a small amount of water comes out the spitter local marine person wonders if was rebuilt correct and the transfer pipe has been missed out thats a lot of work to check that out Mike