Thermostat, reed valves

[St. Johns River Rat]

Mornin' Folks,<br /><br />Aside from overheating, can a thermostat cause<br />other problems on an outboard motor? I have a Force 50 HP, 1990 model. The powerhead seems unusually cool while running. I kinda wonder if <br />this "cooler than normal" has a cause and effect<br />reaction to the performance of the motor. Plugs are correct and new NGK brand.<br />Also, Reed Valves...... can bad valves create a backfiring effect. Motor wants to skip at high<br />RPM's (>3500). Entire ignition system replaced.<br />So now I'm looking in a different direction.<br />Any help would be greatly appreciated.

 

[Franki]

Re: Thermostat, reed valves

Hi, <br /><br />Yes, to cold is bad as well, should be cool enough to keep your fingers on the head for 5 seconds when its at running temp.. <br /><br />After that it should start getting alittle uncomfortable...<br />To test it, take out the thermostat out, and put it in a jug of water with a thermometer and see what temp its opening at...<br /><br />Even better, replace it.. they don't cost much and they should be replaced every year or two anyway.<br /><br />A motor running to cool would foul up plugs quickly and suffer from excessive wear in the long term.<br /><br />As for the reeds.. yes, a reed that is not closing properly can cause all sorts of symptoms, since crackcase compression will drop and alot of the mixture will escape back out the intake..<br /><br />worse, if a reed leaf snaps off.. it can turn your engine into a hand grenade...<br /><br />As for your symtoms, eliminate the fuel system first, its more likely the problem.<br /><br />regards<br /><br />Franki

 

[DumbBass]

Re: Thermostat, reed valves

I recently replaced a stuck-open thermostat on my motor(89 Johnson 60HP) and noticed improvement of idle and less carbon/soot around exhaust. Easy to replace and cheap!

 

[CODE-1]

Re: Thermostat, reed valves

Hi River Rat, go over to the "Nothing To With Boats" forum, would you? I live on th St. Johns too.<br /><br />Ron

 

[9675hpforce]

Re: Thermostat, reed valves

Mine runs to cold also but after changing to 92 octane she runs like a top wonder if all my original problems was the utah 85octane stuff.

 

[St. Johns River Rat]

Re: Thermostat, reed valves

Thank you all for your ideas and comments. I'll<br />play with it some more. Despite the bad rap that Forces get, this has been a good little engine. Just temperamental at times.