1975 Evinrude 75 hp. Water in all three cylinders??

ShoestringMariner

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I just acquired a 75 hp Evinrude. In doing the initial assessment and preparing to do a compression test, We found a lot of grey oil in the cylinders. Turning it over without the plugs blew tons of oily junk out all over the place. We cranked it over until most of it stopped and then tried doing a compression test. The tests were anywhere from 150 psi to over 180.

I don’tthought about getting it running to burn off some of the oil inside and do another round of compression tests.

The motor would not fire and in inspecting the plugs again we found there was a lot more wet greyish oil on all plugs and dribbling out of the plug holes.

Because we had the muffs on, we are wondering if this is water mixing with the fuel and oil.

Any thoughts on what I should check next? Pull the head?
 

F_R

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Either head gasket or exhaust cover gaskets. My bet is on the exhaust cover. Get that motor running immediately to blow the water out, even if without muffs. If it sits with water in it, it is goodbye bearings. Maybe too late already.
 

racerone

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These motors have an oil recirculation system.---That would put water from the bottom cylinder up to the top bearing.
 

F_R

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Absolutely. Those exhaust covers are notorious for warping and leaking, especially if it has been run overheated.
 

racerone

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There is a possibility that water is in the crankcase.-----All over the bearings / rods / journals.------That is not good for these motors.------But from a 1000 miles away we can not inspect / repair this for you.---We can only go by the information as presented.
 

ShoestringMariner

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Thank you, I will try to pull the inspection cover and head off of it tomorrow. Will likely have photos and more questions
 

ShoestringMariner

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Not looking good - Grey watery oil in all three.

I couldn't get the exhaust cover off, do I have to pull the powerhead? The darn lower shroud is in the way.

I'm assuming that what I'm seeing means this powerhead is doomed at this point? Especially if the oil recirculation feature means there's water in the crank case. I'm holding on to a shred of hope here.. But this motor was aquired late last year and has sat since then. I'd have to think that this motor developed this problem back then as the goo was inside when I did a compression check .There was no muffs on then. I thought it might start and burn off the oil. (I figued the oil was that the seller may have sprayed inside to keep from rusting.)

Thanks in advance
 

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ShoestringMariner

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bump...parts motor or could it be brought back from the brink without a major rebuild?

I still dont know what the compression was. We were getting 150-180-150 WET. I can assume it will be substantially less dry
 

ShoestringMariner

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So I had time to mess around with us today. I dropped the lower unit and got it running. Kind of scares The bejeebers out of me running it on a stand without a lower unit. Got it to the point where it would start on carbs without having to feed fuel into the cylinders.

after running a few times briefly, I noticed that were still little bit of oily junk on the mid and low cylinder. I can only assume that this is because there is oil and fuel mixture in the crank case.

And as much as I think this may be a goner, why would water and oil in the crankcase not seize this motor up?
It turns it over smoothly plugs. Nothing gritty. Nothing tight. This condition would’ve happened a year ago almost. Do you guys think it could actually be salvageable?

could this condition cyl head? ( not pulled the powerhead from the midsection yet to check all the exhaust gaskets. I just wanted to get some fuel through it and see if it would run)
there’s no water pump in this motor now. Where is it coming from?
 

F_R

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You want guesses? Or voice of experience? I can tell you that motor has/had water in the crankcase. Probably a warped exhaust cover. Or the whole motor was submerged. If it has not rusted or etched the polished steel bearings, it would be a miracle. In my part of the country (Gulf of Mexico), it would have been a solid glob of rust three days after the water got in. There is only one way to tell, it has to come apart. That's the truth, take it or leave it.
 

ShoestringMariner

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Thanks. I guess I was hoping to hear it wasn’t an automatic goner.

If I chose to open this motor up and rebuild, would it just be a case of replacing crank bearings, a crank polish and addressing the offending gasket/warped plate?

is it the outer plate that warps?
 

racerone

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The crankshaft is the inner race of the bearings.----No guessing allowed.-----Take it apart for inspection.
 

oldboat1

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People do crazy things -- look for crazy fixes in a can. I would collect as much of that goo as I could and let it settle in a clear glass container. If it's a water mix, the water will be visible at the bottom. I think there is a slim chance that somebody dumped Seafoam or something in it -- that it's not water.
 

F_R

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That's a good question. The reason they warp is because they are so thin in that area, and poorly supported, and exposed to exhaust heat. Milling or grinding them flat will make them even thinner. On the other hand, with them being NLA, what is the solution? I don't know the answer.
 

ShoestringMariner

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That's a good question. The reason they warp is because they are so thin in that area, and poorly supported, and exposed to exhaust heat. Milling or grinding them flat will make them even thinner. On the other hand, with them being NLA, what is the solution? I don't know the answer.

I do.

Im parting it out.

I picked up a 1990 70 hp to mess around with instead

thank for the help guys
 
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