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1965 Evinrude Yachtwin 3hp possible bad lower unit

Colezay

Regular Contributor
Hi everyone, I went to drain the lower unit oil on my 1965 Evinrude Yachtwin 3hp and about 50% of the fluid that came out was water. I have not yet used this motor yet and it hasn’t run in about 15 years. Most of those 15 years were spent laying on its side in someone’s yard. Is it possible that water just collected in it throughout the years on its side and slowly seeped through the lower unit seal? I can’t imagine that water would stay in there for 15 years.
 
Also is it worth it to test it like this or should I just run it in a bucket, see if the new fluid becomes milky, then just replace all the seals?
 
If it was 50% water, it is leaking. No, it isn't because it was lying on its side, unless it was lying on its side under water. But then you have junk anyway. Just replace the seals. It isn't rocket science.
 
It could be all rusty and pitted in the gears. I would dismantle and completely inspect. Parts for this lower unit are easily found at a good reasonable price. A pressure test is good, but a vacuum test will confirm positively, a good unit. Be sure to turn shafts and operate shift rods, (if applicable), while pressure and/or vacuum is being applied.
 
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If not here, right through Sierra/Marineengine.....try Tim's Outboard in Hackensack MN for hard to find parts/kits. 218-682-2331 Teresa Mike or Dan.
 
Yes....often my first choice too. Why?? Without the forum, I wouldn't be able to learn from all you guys. Just think how some stupid people will order cheap foreign made parts.....replacing stuff unnecessarily......instead of asking for help first, right here on the forum......then getting directed immediately to the problem. This league of experts can easily outdo many top end shops, with only a picture or two and some accurate answers to questions directed at the boat owner.
 
Tim's can send out tomorrow. Give em a call with the model #. They have been around about 55 years. Tim is still active, would love to get him as a forum tech here.
 
Just sent him an email. Last two times I contacted him he didn’t have the part, but to be fair they were pretty random parts off obscure engines lol
 
New seals and also new seals to the fill and drain plugs too. I always like use more expensive lower unit - oil on my Lightwin 3hp, because that particular oil should prevent failures, if fresh sea water find its way inside the lower unit.
 
Ok ive taken the lower unit mostly apart. I’ve gotten down to the gearcase head behind the propeller and it won’t come off! I don’t want to damage it in any way but the thing is stuck on there.
 
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They might have used Permatex to seal up the joint between the bottom cover/skeg and the lower housing. Try a rubber mallet and give it some persuasion. Don't try to pry between the two or else you'll damage the sealing surfaces.
 
15 years of sitting with water in it may have caused some corrosion. Anyhoo, there is an o-ring around it. See if it will rotate a bit. If it will, try rotating it back and both as you pull. The problem is getting ahold of it to pull. Avoid the temptation to pull or beat on the ears, because they will break off. The best way is to rig up a slide hammer on the prop shaft to yank the whole thing out.
 

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That should help. If there is corrosion, try soaking with a 50/50 mix of acetone and auto tranny fluid. Acetone is nail polish remover, but I buy in larger quantities. Use for paint and pyrotechnic/rocket fuel production.
 
the whole prop shaft slides out? I didn't know that. I can't even get the gear case head to turn by hitting it with a rubber mallet. How would I get a slide hammer on the prop shaft without damaging anything? I'm assuming I should probably get the gear case head at least twisting a little before putting a slide hammer on the prop shaft.
 
Gator probably has a slide hammer with a washer type end........put it into prop shaft, then just put the prop nut on and bang away. I haven't made one but it's in the works.
 

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Wish I had the skills to make one... would it be possible to remove the prop shaft seals without taking that gearcase cover off? No matter what I’ve tried it still won’t break loose
 
Link: Slide Hammer and Puller Set, 14 Pc. (harborfreight.com)

I don't remember, I might have had to make a suitable coupling nut to adapt to the prop shaft threads, Anyhoo, the deal is attach the puller to the prop shaft and bang away with the slide hammer to yank it out.
So all I would have to do is put that attachment on that looks like a long nut? Could I use that to pull the seals out as well? This motor definitely has the original seals
 
Its likely not the correct threads. That other little attachment that looks like a fork might work, but it's kinda stupid because it's gonna slide off. They should make an attachment like in my drawing.....detail see below. Then you can just use the original prop nut, and the force will direct squarely.
No, once the housing has pulled out with the shaft, you take the shaft out of your way and push out the seal from behind with something like a punch.
 

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Fat chance it will have the right threads. Gotta make something like my drawing.....it's not patented yet....I give you permission.
 
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