'83 Evinrude 115hp driving my crazy(water pump)

ashedd

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I have an '83 evinrude 115hp that had to be pressed into service because the old mercs that came with my new(1966) boat were in bad shape.

So I fight with the corrosion to remove the lower unit to do the water pump, get it back together. Old impeller needed cut off. It was pumping fine but one side of the motor was getting too hot. I removed the two hoses from the heads to the thermostat cover and water did flow from the heads when running(I'm using muffs).

So I continue on to the thermostats. All three bolts required a torch(and I mean ocy acetylene) and kroil to get out, with one of them snapping and another requiring the bolt head to be melted off. This took a week on and off. I order all new parts due to corrosion, new cover, spacer, bolts, and the usual thermostats, bypass valves, springs and gaskets. Thermostats were basically solid corrosion. I get it all back together and no water is being pumped, I mean nothing from the pee hole and nothing from the heads with the tubes removed. I got water to flow with the garden hose from one head to the other ok. I pulled the thermostats, bypass valves, and spring just to see if that helped and still nothing. I'm guessing I need to remove the lower unit, again, and check the impeller then try to get water up the tube into the motor from the garden hose.

I did try to remove the lower cowl to get to the thermostat cover bolts better, didn't work. I also took some bolts out for the motor mounts in prep for lifting the powerhead. I quickly determined that was way more work than I wanted. I ended up drilling holes in the cowl to get to the bolts straight on.
So I'm pretty annoyed at this point. The twin mercs had to be removed, and this evinrude I got with another boat(that sat) needed more work than I wanted. I would like to get my "new" boat in the water. I feel like just putting my old trusty '67 20hp johnson on there if I didn't think it would be too slow for any fun, and I need a longshaft.

WHAT COULD CAUSE THIS MOTOR TO STOP PUMPING?

Thanks
 

emdsapmgr

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When you had the thermostat housing apart, did you inspect the plastic valve body? There are a couple of pinholes, each of which lets hot/warm water trickle onto each of the stats. It is this warm water that causes the stats to open. If these two pinholes get plugged with debris and won't flow water, the engine will overheat, despite new stats, springs, etc.
 

ashedd

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The valve body is also new. I destroyed the other one with heat. I saw the pin holes in the new one
 

ashedd

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Any other ideas from anybody? I'm going to try to fix it tomorrow
 

ashedd

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on muffs when I got water the first time and on muffs when I no longer got water. The water pressure at the muffs was really high too, I got plenty wet. I don't have a tub that size, would have to go buy something.
 

ashedd

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I think I'm gonna give up on this motor...

Pee hole outlet from case was blocked, fixed that. Took lower unit off and was able to run the hose to the cylinder head water jacket(both sides) "spouts"(without the hoses on) and got water out of the water line going to the impeller. I was also able to run water from the same line on the bottom and get water out of the head jackets. Ran water to where the thermostats go(removed along with the valves) and kinda sometimes got water from the bottom line, same with the reverse. And there was another combination where I got water to flow but can't recall. So perhaps deflector thingys I've read about at the bottom of the powerhead are toast, or there are other water passages in the block that are plugged up with corrosion.

On top of all that the trim gave out on me. I had to undo a screw on the left, remove a spring, pull out another part, then press the valve/needle with allen wrench to relieve presser as I pushed the motor down from it's full up tilt.

I think those deflector things require a powerhead removal to replace, I'm getting sick of being an outboard mechanic. At my wits end here.
 

Fed

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You only have to remove the cylinder heads to change the deflectors not the complete power head, it's a pretty easy job aside from the potential broken bolts.

Sounds like you undid the wrong valve on the PTT, should have undone (2 turns) the by-pass valve on the starboard side.
 

ashedd

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bypass valve didn't come out and the screw head is now stripped.

Would deflectors cause the problems I've described? Because if they're under the heads I wonder if they're the problem since water seems to flow to through the top of the heads just fine, mostly.
 
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Bosunsmate

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Dont worry too much, lots have being here and seen their motor come good.
First thing first, keep the lowerunit off, only put that back on when its certain the powerhead is all working ok.
To do the deflectors you just need to remove the heads as Fed says above.
And yes you need to check up on them as this motor sounds like it needs some care and attention.
I dont quite have a picture of whats going on on this motor yet, when you connect the hose to the waterinlet up the leg, dont turn it on too high, you can damage stuff, but does water come out the bottom of the head where you have removed both hoses?
 
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ashedd

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No, water didn't come out the bottom where the thermostats go. I actually have the thermostat cover and spacer off and didn't get any water. I may have gotten a tiny bit of water once, I don't recall. I think the water comes from the impeller through the heads and down to the thermostats and out the bottom of the power head. Sound about right? I keep the thermostat cover on most of the time, and I don't hook the hoses back up unless water comes out of the heads.
 

Bosunsmate

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No, water didn't come out the bottom where the thermostats go. I actually have the thermostat cover and spacer off and didn't get any water. I may have gotten a tiny bit of water once, I don't recall. I think the water comes from the impeller through the heads and down to the thermostats and out the bottom of the power head. Sound about right? I keep the thermostat cover on most of the time, and I don't hook the hoses back up unless water comes out of the heads.
Yes thats correct, im wondering did it make it to where the hoses go from the head to the thermosat, ie has it made it through both heads ok?
 

Bosunsmate

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ok, ive got to go do a couple of things, so i will assume you will answer that as a yes, so the next thing is to shove your hose in to the thermostat housing and make sure that it drains properly down there, ie that the lower exhaust plate is not gunked up.
If that flows fine and you are happy with your thermostat body ( i always drill that middle drain hole to be twice its current size) then put it all back together and run the motor, using the hose (not on high pressure!!) attached to the inlet pipe in the leg.
Keep a check then on both heads, if its not good then you will need to check the deflectors
 

Fed

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The deflectors are there to force the water to go up and over the top cylinders, they stop the water taking a short cut between the top & bottom cylinders.
What happens id corrosion builds up between the cylinder walls & the deflectors & squeezes them into the water flow path.
Here is a picture of one exactly how it should be and a picture of one being pushed out.
Water diverters.jpg

deflectors.jpg
 

ashedd

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Yes thats correct, im wondering did it make it to where the hoses go from the head to the thermosat, ie has it made it through both heads ok?

yes, I can get water out both heads from one side to the other in both directions.
 

ashedd

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well if that's all the "deflectors" are then I guess I'll try it. I'm not looking forward to breaking any bolts but I've only broken one so far and that was before I perfected my technique. Oxy acetylene can really heat things up. So I'll need head gaskets and the gaskets for that big square cover between the heads since I removed it too. I also need to find a way to seal the garden hose to these spots I'm trying to run it. It's hard to tell where the water is coming from at times. It seems to me that the water doesn't want to flow out the bottom after the thermostats like it's supposed to. Or the other way when feeding from the bottom.
 

emdsapmgr

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Did you pull the cyl head covers off each head and check the water passages in the heads to be sure they are clear and will permit water flow thru them?
 

ashedd

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Did you pull the cyl head covers off each head and check the water passages in the heads to be sure they are clear and will permit water flow thru them?

No not yet, that I'll do monday I guess. I got water to flow out of those heads with the motor running once before. It was after a replaced the thermostats that it all seems to stop working. I originally thought all the heat I used on the bolts caused a problem, but I now can't seem to think how that would be the case.
 
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