1982 evinrude 15 cooling

[suthernoutlaw]

i just put a new impeller and housing on my 1982 15. wasn't peeing through the hole on the back right side of the case. i took off the cover where the tstat is and there wasnt one in there. i know that cant be the problem because it was spraying fine. the hose on the tell tale and end was clogged a little but i unclogged it and the water gets to it and drips a little and some air bubbles, but no spray. pulled the foot back off and i can blow through all the lines. with the tstat plate off i cranked the engine and no water is coming up? maybe it has to be on for it to come up. it would help if i could find out any more on the cooling system of this engine. where else could there be a blockage? thanks for any help....

 

[Rick.]

Re: 1982 evinrude 15 cooling

Your water pump is in the leg so it must be on in order for water to pump. Try pushing a wire or weed eater line up the tel tale hole (while motor is running) to see if it is plugged. When reinstalling your leg, be very careful that the water tube is fitting nicely into the grommet on the water pump. I would suggest you get the right thermostat for your motor. It is engineered to have one to keep the operating temp. at a constant. I have an 82, 15 HP and I get lots of water out the tell tale. You never said if your using muffs or a barrel to test it in. If it is a barrel make sure the leg is well submerged in the water. Like 1/2 way up the leg. Enjoy, Rick.

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

im using a barrel and the leg is submerged to the water line it sets on the boat in water. i had a little clog before in the tel tale line but now i can blow through it easy while not running. while running i tried to suck water through, bad idea, very hot and it didnt want to come out. where does the water line go that comes up from the foot? with the lower unit off i can't blow through that line. when i tested the line was perfect in the grommet on the pump housing on impeller. is there anything in the cooling system up from the pump assembly that has a restriction? i thought it should pump up from the foot and flow free through the engine with no restriction. thanks again...

 

[Mas]

Re: 1982 evinrude 15 cooling

Is your motor overheating? Can you leave your hand on the head for a three count with out burning? If you can't, your impeller may not be pumping, or there is a restriction in the water passages.

MAS

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

it is getting hot. im thinking a blockage in the water passage. i think its the line coming up to the bottom of the engine from the impeller. i cant blow through it. should this be easy to blow through? is there anything in the engine water passages that create a restriction or should they all be easy to blow through? if i had a diagram of the water passages it would help. i dont know where the water goes once it goes up the tube from the impeller.

 

[Mas]

Re: 1982 evinrude 15 cooling

Sounds like it's time to drop the lower unit and have a look. Several things could be wrong:

Impeller disintegrated blocking water flow
Impeller spinning on the drive shaft
Grommet for water tube is pinched
Scaling in the water passages is constricting flow
Sucked up some debris that is creating a blockage

Take your pick,

MAS

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

i already put in new impeller and housing, the old one was still in good shape. i've had the lower unit off four times now to check everything. i made sure the water tube lined up and went in the grommet on the pump housing. im thinkin water tube is clogged should it be easy to blow through? or have resistance? i can barely get air through it

 

[Mas]

Re: 1982 evinrude 15 cooling

Are you using compressed air...or puckering up?

I have never tried it, but you should be able to blow compressed through. If water is still in the passages, it might be difficult to force standing water out without compressed air. If you are blowing up from the pump side, you might be lodging debris even tighter. It's better to do so from the outlet side.

MAS

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

yes, compressed air. first it was hard to blow through the nipple where the water exits the tell tale. cleaned that line and nipple then pulled the tstat housing off and cleaned everything. cranked the engine with the tstat housing off and no water was coming out? there is a big hole where the tstat sits and at the other end of the water jacket a small hole. the small hole was pulsing air out. should it do that? and was no water coming up. because it needed vacuum from the air coming out the hole? all back together and blew easy through, but the line coming from the impeller housing will not blow up through it. is there anything else to prevent water or help it through the engine? or just the pressure of the impeller pushes it through the engine? thanks again

 

[Rick.]

Re: 1982 evinrude 15 cooling

Well you have free passage to the pee hole but that doesn't cool the engine. The water that goes up the water tube from the pump goes through the engine, thermostat and that plate you removed and eventually 90%+ goes down your exhaust and out the prop. A little goes out the pee hole but that just tells you the pump is working not that the engine is cooling. I suspect your not getting any cooling at all based on what you've found so far.

Here is what I would suggest next. Pull the leg again, hook up a hose directly to the water tube and turn it on and leave it on until you get a good flow coming out the stat hole. Really flush it good.Once you get it flushed then put it all back together and give it a go in the barrel again and you will find all is well. Just remember the pee hole water does not indicate the engine is cooling, only that your pump is working. Let us know how it goes. One more important thought. Make certain your intake screen is clean and the pump is getting a good supply of water. If the leg has filled with silt and it has hardened, you will need to pull the pump and flush under it with water to clean the passage to the pump from the screen. Rick.

What can I say, I'm not a muff man. After some thought, if you have a muff you could put it over the water inlet on the leg and if it were plugged below the pump you could flush it with the muffs. I only ever use a barrel so didn't think of that. I would still hook the hose directly to your water tube though.

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

i changed the intake screen to a new one. all is clean and i blew through the water line and seems nothing is clogged. while running it has alot of steam coming out the tell tale hole and water spirts every now and then, not constant. the engine is running excellent except for the water problem.what would be making steam and why is it only coming out in spirts?

 

[Rick.]

Re: 1982 evinrude 15 cooling

Your going to have problems if you keep running it with no cooling. That steam is evidence your not cooling the motor. I have no idea what is causing the poor circulation but I really think a good flushing with water (as I said earlier) is what you should try next. Compressed air doesn't have the same effect as running water. Water will hopefully loosen what ever material is stopping the flow. Air typically wont do that. Give the water a try. Once you establish good flow out the thermostat hole button the cover back on it and try it in the barrel. Rick.

 

[suthernoutlaw]

Re: 1982 evinrude 15 cooling

i think i may have it fixed. i tried and couldn't get water to flow good through the stat hole. i pulled the engine off, and pulled the exhaust cover off the side of the engine. it had so much build up of crud lodged everywhere, don't think it could have gotten any worse. cleaned it all up, gotta get a new engine base gasket and exhaust gaskets. i'm hoping when i get it all together it works. i know that's where it was clogged so.... thanks for all the help, really appreciate it. every job learn more things. one more thing the copper tube coming up to the engine has i tiny hole towards the upper portion. is this a relief hole or is it suppose to be there? maybe sprays to cool exhaust? housing?

 

[Rick.]

Re: 1982 evinrude 15 cooling

No idea about that hole. If it small it wouldn't hurt anything. Please for my sake run the hose on the water tube to give it a good flush or are you certain your getting good water flow? Glad your starting to get some answers to your problems. When it's all said and done sounds like your motor is a good candidate for a decarb. That might move your compression up too. On second read of your last post it sounds like you pulled the head. You could easily patch that hole with a little 50/50 solder while you have access to it. Rick.