20 Hp Evinrude -83 with cooling problems ?

[andm]

Hi !
I just bought me a 20 Hp Evinrude that the former owner claimed that it had cooling problems.
He told me that they had change the impeller and after that tested it in a barrel but it still gets warm.
I took a chanse and was planning to change the thermostat and check the water inlet chanell.
When checked the motor I noted that it have a new gasket were the thermostat are situated and also the water inlet seems to be ok.
I started up the motor in a barrel and at first it dident came out any water from the small hole under the motor. Stopped the motor cleaned the tube that is connected to the small hole and started it up again, after a while it started to come warm water from the small hole, but no water from the bigger holes.
I know that it could be some problems to get the cooling running properly in a barrel so I will try it on the boat, but I have some questions that I hope someone could answer or get me some ideas.

When it start comming water from the small "pee hole", does it indicated that the impeller is working, and does it also indicate that the thermostat is open ?

So it will not come any water until the thermostat will open at 145 F ?

 

[Will Bark]

Re: 20 Hp Evinrude -83 with cooling problems ?

Water from the pee hole indicates that the impeller is working; it does not indicate that the thermos is open. Should be about 145* and some water should come out of holes on leg close to the cowling with more coming out by prop.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Ok Thank You for the answer !
As it was a new gasket in the theromstat aeria i presumed that they had changed the thermostat, but I am not shore.
I think I in someway will measure the temperature on the head and run it the barrel one more time and see if it starts to come out water from the holes on the leg close to the cowling.

 

[Will Bark]

Re: 20 Hp Evinrude -83 with cooling problems ?

The best way to measure temp is with an infared Temp meter which uses a laser light; I got my from Harbor Freight over here but I haven't the foggiest idea were in Sweden you could get one. Just go to Google and find out.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Yes thats what I had in mind also, I have used one in my job earlier.
Could be hard to get one today as it is the Swedish Nattional day today, but I will give it a try.
I have also seen that there is some app to the iphone for this but then I guess You need to get some sensor for it.

 

[Will Bark]

Re: 20 Hp Evinrude -83 with cooling problems ?

Years ago I watched a very good mechanic test my motor for overheating by putting drops of water on the top of each cylinder head; he said if the water just stayed there it was not overheating but if it dried up quickly it was beginning to get too hot and if it started boiling it was definitely overheating. This was his way of quickly testing; probably not the most accurate way in the world.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Oh that was a good and easy methode. However havent managed to get an IR-thermometer yet. Started up the motor no water came from the peehole at the beginning, but after some minute it started to come out hot water from the peehole and I was burning myself when I put the hand on the top. Removed the plate that holds the theromstat ( with the new gasket) and surprise surprise there was just a spring and no thermostat and no water.
Started up the cold motor and after a while it started to came out hot water from the peehole and at the same time it stated to come out water from the hole in bottom were the thermostat shall be placed. It flows out water but I dont now if it is enough. Is this as it shall be ?

 

[Will Bark]

Re: 20 Hp Evinrude -83 with cooling problems ?

Take your hose and backflush thru the hole where the thermo goes see if you can get anything to come out going the other way may be able to knock something loose that's stopping up the passages; may work.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Took my preassure wash and backflushed from the hole in the thermostat botton, the water came out in the peehole so I put a finger to block it and continue to flush. After that I started the motor and now the water started to come out from the thermo hole and the peehole right from the beginning, but I think the preassure isent enough as the water just flows out and I think I expect it to squirt out from the hole in the thermostat botton or ?
I will continue tomorrow.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Wasent any time for this today, but how much water and what pressure can I expect comming out from the hole behind thermostat ?
I read at Welcome to LeeRoy's Ramblings that they made a peehole in the lower cowling of a 15 hp Johnson and out of that the water squirted more than 6 feet at high rpm`s.
Hard to try high rpms`s in a barrel, but shall I expect a squirl even at low rpm`s ?

 

[tomhath]

Re: 20 Hp Evinrude -83 with cooling problems ?

Just because they changed the impeller doesn't mean they did it right. It sounds to me that the water tube is blocked. Probably the remains of an old impeller is in there.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Yes I suspect something like that, I will take it apart today and check.
Thanks.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Have taken the motor appart, impeller and everything looks ok. I have flushed the system both with water and highpressure air. Put it together an started it, the water is comming from the peehole and flows out from the small hole behind the thermostat, I just hoping that it is enough. Now I just waiting for a new thermostat so I can assamble that and see if it will be warm or hot.

 

[andm]

Re: 20 Hp Evinrude -83 with cooling problems ?

Got the new thermostat and put the motor back togehter. And Yes it seems to work as it supposed to. The water starts comming in the peehole after aprox 20 seconds and then when the thermostat opens, the water starts comming from the holes on the leg close to the cowling. The motor gets warm but not hot, and I did the waterdrop trick and the drops stayes and will not dry up quickly.
So it seems like there must have been some leftovers in the system from the old impeller or so that I manage to flush away.
Thank You All for the support !