Overheating Outboard

[Martoony33]

Greetings to one and all!<br /><br />I own a Honda 4-stroke BF50 S 5 h.p. motor.<br /><br />* It runs very well for about 1.3 hours, then it seems to overheat. The motor stalls and stops. After 5 minutes, you can restart the motor, but it will die if run at lower to idle speeds.<br /><br />* The tell tale is working -- I have a goodly amount of water spritzing messily out of the tell tale, although it doesn't come out in a clean, steady stream (like a fountain figure in a garden).<br /><br />* My assumption is that the impeller is working, because the water volume coming out of the tell tale is decent. <br /><br />Is there such a thing as a thermostat with these units? Could that be the problem, or is something else more likely?<br /><br />Many thanks for the kindness of strangers,

 

[letsbarbq]

Re: Overheating Outboard

welcome martin,<br />I wish i can help but I only owned 2-cycle. for the 2 cycle we do have thermostats. if you follow the water line and it is usually on the head.<br /><br />hope this helps.<br /><br />if it is so new do you have warranty?

 

[9675hpforce]

Re: Overheating Outboard

the thermostate should be ta en out and run to clean any roc s and crap outa there.

 

[Fouled Plug]

Re: Overheating Outboard

Sounds like perhaps some crud in the tell-tale hose. Remove it and blow it out if possible, may be restricting flow enough to heat up the motor.

 

[jim dozier]

Re: Overheating Outboard

Tell tale pee streams are only visual indicators. If they are clogged the engine won't overheat unless there are other cloggs (possibly due to the same kinda crud) in the cooling channels. <br /><br />Get a manual. I don't know that engine, but if it has a thermostat that's the first thing to check. If you find it, take it out and test it in a pot of water with a cooking thermometer. Run the engine on the muffs with the thermostat cover off and flush the engine (you should get a geyser out of the thermo hole). <br /><br />It sounds from your description like your impeller is possibly not up to snuff and might need to be replaced. They have a shelf life and if its been more than 2 years since it was replaced you should probably replace it as a matter of general maintenance.

 

[Martoony33]

Re: Overheating Outboard

I appreciate everyone's advice. I will do the following:<br /><br />* Get a manual for this unit<br /><br />* Replace the thermostat -- I am sure this has never been done in the last ten years.<br /><br />* Replace the impeller -- I think it's older than 2 years.<br /><br />* Run the engine with the thermostat and respective casing removed, in order to flush out any blockage from cooling system.<br /><br />* Make sure individual segments of cooling lines aren't plugged.<br /><br />Chances are, I don't need to do ALL these things, but thermostats and impellers are cheap, relative to the alternative of cooking the motor!<br /><br />Thanks for everyone's help!<br /><br />Marty

 

[Martoony33]

Re: Overheating Outboard

WOW!<br /><br />The old thermostat appeared to be jammed and bent out of shape (off-axis). I took it out and flushed the motor out for 5-10 minutes. Needless to say, I replaced it. Even more water seems to come out of the tell-tale hole -- still it's a messy spray. I will replace the impeller, as soon as the kit I have ordered arrives.<br /><br />Thank you to everyone for your advice.