9.9 Evinrude-How hot is too hot?

[catalyst-519]

I have a 9.9 Evinrude. Thermostat was rusted in the open position and I recently changed it.

With the old thermostat the motor blew out a lot of water with the ehxaust. It's an older model without the pee hole. Now since I've changed the thermostat it only mists out water, to the point where it's not visible unless you hold your hand in front of the exhaust.

I've read other posts that suggest a worn impeller, but with an open thermostat it ran plenty of water, so I'm not so sure that's it. (could new thermostat be defective)

I;ve also read about the 3 seconds to touch, but even the flywheel is getting real hot, 1-2 seconds to the touch.

Also, after running about 30mins, it stalls out in low idle or when trolling.

How hot is too hot? What kind of damage can it cause? What steps should I take next?

Cheers---519

 

[plmbr]

Re: 9.9 Evinrude-How hot is too hot?

I'd check the impellor myself to see if it is worn out because as you were saying with the open thermostat it spit out lots of water and now with the new thermostat it isn't. That could be that it's worn out enough to not have the pressure to push it thru. It's very simple to drop the bottom end off and check the impellor. I had a similar problem with my 9.9 it was heating up and you could fry eggs on the flywheel, which in turn ruined my rings and one piston from running so hot. I rebuilt it and replaced all the gaskets and a new impellor and now I can troll or drive wide open for a long time and the water comes out the pee hole of which mine has at a srong force also out the exhaust relief holes at the top on the outer exhaust tube and the flywheel is cool to just barely warm. And as the thermostat goes the try taking it out and go without it and see what it does.and then go from there

 

[tashasdaddy]

Re: 9.9 Evinrude-How hot is too hot?

impeller should be changed every 2 years.

 

[iwombat]

Re: 9.9 Evinrude-How hot is too hot?

Yep, do yourself a favor and just change the impeller already. If you have an infra-red thermometer that's the best way to check the heat, but it sounds like it's getting too hot anyway.

New impeller - or better yet, new waterpump kit.

 

[OptsyEagle]

Re: 9.9 Evinrude-How hot is too hot?

I am certainly not arguing against an impeller change, however, you did not state the year of the motor in question.

I own a 1975 9.9 Hp (this will be the same for 1974 to 1976) and the spray out the exhaust starts out as just that, a very light mist. Then it increases significantly in about 30 seconds and then oscillates from a mist to a good spray and back again. I was told that in these motors, the larger spray only happens when the T-stat is open. When it closes you get a lighter spray. This could be what you are seeing.

I run mine wide open for long periods of time like this. I can touch the head after a good run, but I would not want to leave my hand on it for too long. It should be at around 145 F and this is a fairly hot temperature to touch. It won't burn, but will be real uncomfortable. If yours is hotter, then you definitely need to look into this further, but that is how my motor works.

 

[catalyst-519]

Re: 9.9 Evinrude-How hot is too hot?

Thanks for all your replies. Optsy: it's a 76' Model 10655R, so essentially it's the same motor as yours. What I'm finding is that there is no intermittent variation of water discharge, even when it's hot enough you'd think they're should be more spray. Just a consistent mist since changing the thermostat.

I'm going to pull the lower end and have a look at the impeller. Is there any logic to changing the entire pump and seal (while I'm in there)?

Optsy: Did you consider the conversion to a tell tale and pee-hole water-exhaust system? I found some instructions for the conversion but it seems a little complicated on an electric start system.

Either way, sounds like that impeller needs to change, if only for good measure anyway.

How about the stalling after it heat's up. If a motor is too hot, would this cause it to stall at low idle?

I'm so glad this forum exists. Thanks to everyone for their time on this one.


Cheers---519

 

[Solittle]

Re: 9.9 Evinrude-How hot is too hot?

If it gets too hot it will bind up and stall.

 

[OptsyEagle]

Re: 9.9 Evinrude-How hot is too hot?

You might also want to recheck your new thermostat and make sure that for some reason that it hasn't failed closed or is causing some restriction of the water. If that were the case then you would only see a slight mist out of the exhaust hole and of course she would definitely overheat.

It would be nice to have a tell tale but not enough to get me to start drilling holes into perfectly good motors. I just don't like the thought of that, but that is me.

Good luck with your motor.