Evinrude 90hp no Thermostat

[eula30]

Hi, I have a 1986 90hp Evinrude without temperature gauge (no way to now if the motor is to hot). I notice that the water coming out thru the pee hole was to cold and on 5000 rpm, the pee pressure will lose a lot of pressure, I change the impeller no luck, so I decide to check the thermostat and there was no thermostat, when install new thermostat the pee pressure was low for about 30 seconds then a get a very strong pressure thru the pee hole, the highest I go on RPM the strongest the pee pressure is. But the problem that I gat now is that before I can touch the Motor head with my hands and they wore cold now they are two hot for my hand I can only leave my hand for about 15 seconds before I get burns and I’m afraid that the motor is running to hot. My question is: Can run this motor without thermostat or they have to have thermostat? Since I don’t have a pressure gauge and afraid of overheating the motor..<br />I really appreciate any help.<br />Thank you

 

[ob]

Re: Evinrude 90hp no Thermostat

eula30,Sounds like its running normal temp to me.The better pressure at the tell-tale with the thermostat installed is due to the back pressure it imposes on the water passages.If you are concerned as to whether the engine is running above its designed temp,get yourself a 163 degree thermo melt stik or a temp gun and check the head covers and block when the engine is up to temp.

 

[eula30]

Re: Evinrude 90hp no Thermostat

Tank’s OB<br /><br />I will get the thermo melt stick tomorrow and try it out. <br />Do you know how much it will cost to install a temperature gauge?<br />Thank you

 

[Cricket Too]

Re: Evinrude 90hp no Thermostat

I agree with ob, sounds like your running normal temp., you should only be able to hold your fingers on the head for a couple of seconds 2-4 before having to pull away, 15 may even be too long. Good Luck.

 

[rickdb1boat]

Re: Evinrude 90hp no Thermostat

Temp gauge and sender. Some wire and a little work. About $75.00, if that.<br /><br /> Gauge <br /><br /> Sending Unit

 

[Dhadley]

Re: Evinrude 90hp no Thermostat

I would agree with all the above. Sounds like the motor is running good. The question is -- are you having fun?

 

[My Fling]

Re: Evinrude 90hp no Thermostat

Hi,<br />I would like to fit two VDO sending units to my Evinrude 115 on my Fling with Turbojet.<br />Before I order the guages/sending units, can someone please explain where the Sending Units fit and how much work is involved in fitting them.<br />Thanks,<br />Nigel

 

[eula30]

Re: Evinrude 90hp no Thermostat

Ok, just came from the water, ran the boat for 2 hours, and it run really good, I guest thermostats are very important on outboards (didn’t now that), I believed it is running faster, before was doing 28 to 30 mph, now is running at 35 to 38 mph, at 5000 to 5100 rpm. That is really good for me. So I’m very happy now. I want to Thanks all of you who are always there helping us.<br /><br />Thank you<br /><br /> PS: Fuel filter on the motor is getting a lot of dirt, I believed fuel tank (internal) it have to be really dirty, is there any way I can clean fuel tank,?

 

[Solittle]

Re: Evinrude 90hp no Thermostat

On the temp guages - They attach to one of the head bolts and the sender touches the head with a single wire running to the guage.

 

[eula30]

Re: Evinrude 90hp no Thermostat

Any idea why I’m getting a lot of dirt in the fuel filter? Is the water separator suppose to work as a filter also?<br />Thank you