1983 Evinrude 15 HP Not Pumping Water

[Sparhawk59]

I have been working on rebuilding at 1983 Evinrude 15. I converted it from a long shaft to a short shaft, replaced the water pump assembly and impeller, drive shaft, cut down the water line and a "boat load" of other repairs ranging from a new tiller handle to the idle control knob assembly. Today, I tried to start the engine, which was successful. But it is not pumping water through the tell-tail. I removed the lower unit assembly, and checked the water pump. Everything was good. I also took an air compressor and blew air up the copper water line and could feel it coming out of the tell-tail. Re-assembled again, and tested with a tank (not the original hose clamp). Still no water out of the tell tail. So I removed the thermostat housing. No undo amount of corrosion, but also no thermostat. Also the area looked dry-like it had not seen water in years. So I have ordered a new thermostat. I know that air will go up the water line and come out the tell-tail from the compressor test I did, BUT what else am I missing? It does appear that water is not making it up the copper line-and I have double checked the assembly including the pump to copper line connection. Where do I go from here? Any suggestions are appreciated.

[racerone]

Water in your test bucket must be 6 to 8" above the pump impeller.

[Sparhawk59]

Water in your test bucket must be 6 to 8" above the pump impeller.

I used a set of "hose ears" the first time and for the second attempt I used a tub with the water up over the cavitation plate-but not up to the plate above the cavitation plate. Shouldn't the ears worked-the provide water to both sides or the lower unit intake. As for the tub, I thought the water only needed to be to the cavitation plate?

Thanks, Chris

[Rwbutler]

I used a set of "hose ears" the first time and for the second attempt I used a tub with the water up over the cavitation plate-but not up to the plate above the cavitation plate. Shouldn't the ears worked-the provide water to both sides or the lower unit intake. As for the tub, I thought the water only needed to be to the cavitation plate?

Thanks, Chris

Its not a suction pump...

[Sparhawk59]

O.K.

It been about two weeks now. I removed the thermostat housing and head. Passages looked good for a 35+ year old motor. The thermostat was missing so I did some cleaning, and install new thermostat with hardware, and reinstalled the head and thermostat housing with new gaskets. I bought a trashcan and used it to water test the motor, filling the can up past the cavitation plate to above where the water pump is located. Still do not have any water pumping through the tell-tail. So far, I have replaced the water pump housing and impeller, pumped compressed air up the water line-with air coming out of the tell-tail, replaced the thermostat and head/thermostat plate gaskets and done the compulsory cleaning out of the tell-tail with a wire. I like the motor-it starts and runs well and I have alot of parts and money in it at this point. Where do I go from here?

[Rwbutler]

O.K.

It been about two weeks now. I removed the thermostat housing and head. Passages looked good for a 35+ year old motor. The thermostat was missing so I did some cleaning, and install new thermostat with hardware, and reinstalled the head and thermostat housing with new gaskets. I bought a trashcan and used it to water test the motor, filling the can up past the cavitation plate to above where the water pump is located. Still do not have any water pumping through the tell-tail. So far, I have replaced the water pump housing and impeller, pumped compressed air up the water line-with air coming out of the tell-tail, replaced the thermostat and head/thermostat plate gaskets and done the compulsory cleaning out of the tell-tail with a wire. I like the motor-it starts and runs well and I have alot of parts and money in it at this point. Where do I go from here?

Inspect waterpump,cooling system starts at intake screens

[racerone]

Water must be 6 or 8 " above the impeller.-----Is the motor getting HOT ??----Does water sizzle on the cylinder head if you sprinkle some on there ?------Maybe the tell tale fitting is plugged ?----Or bring it over as I think it is an easy fix.

[Sparhawk59]

I will try it again tomorrow. I don't think the fitting is clogged since I ran compressed air up the water line in the lower unit and some did come out of the tell tail. The motor doesn't appear to be getting hot, but then again, I don't let it run too long. I'd love to bring it over, but I doubt we may live near each other. I will let you know how it goes again tomorrow. Thanks, CAW

[timguy]

Couple ideas here for you. Might be that air will pass through under high pressure, but water can't. Why? There is a sealing sleeve/ring at the top of the copper tube. This often fails and plugs things up. Must remove powerhead to repair it. If you feel that there is no restriction at that seal, then I wonder if you installed the impeller with correct rotating direction? This means while looking from bottom, and with pump housing in your hand....looking at the impeller as your putting it in place....Turn It Counter Clockwise. Next....as mentioned before....no blockages between intake screened openings and the water pump inlet, (that's the hole in the water pump base directly into the impeller housing). Make sure impeller key is in proper position....AND water level at least 4" above the impeller/pump. If all this is properly accomplished...it WILL PUMP WATER.

[Sparhawk59]

Success! I raised up the trashcan, filled it full of water to abut six inches above the water pump and everything work great. It pumps water like a champ. Thanks Timguy! I never though the water needed to be that high, but you learn something new every day. No it's time for pre and paint!

[timguy]

Praise be to Old Racer.....this is something he ALWAYS makes well known.

[Edchris177]

Praise be to Old Racer.....this is something he ALWAYS makes well known.

Yes, & despite knowing this I got caught. The pristine 1974 6hp Evinrude didn’t appear to be pumping, even though I had around 4” above.
filled the can to the top, water flowed...lesson learned. Put it on the tinny & ran it full throttle for half an hour.
Racer May sound a little crusty on the forum, but in real life he’s a pretty nice fellow to chat with. Interesting guy, with a yard full of parts, & a high speed boat project on the go. I do all my own work on cars, even down to pulling heads, but for these kickers...Anything complex at all I just bring to Racer.

[timguy]

We got camps in NW Ontario....guess you guys are out east. We have some amazing talent here on the Forum.....amazing.