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1984 8HP Water Pump Drive Pin

jack1

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"I have a 1984 Evinrude 8HP E8

"I have a 1984 Evinrude 8HP E8RCRM that was given to me with water in the gearcase. I purchased the parts I needed to repair and replaced them also rebuilding the water pump. My problem is I can’t place the pin that goes between the water pump impeller and the drive shaft because I can’t get the drive shaft out. The book I have, which is a 1973 – 1990 multi motor manual, seems to indicate that the drive shaft is connected to the motor with only a spline and can be pulled straight out through the midsection, inserted through the water pump and into the gearcase. Then the whole assembly reattached to the midsection with the drive shaft fitting back into the spline. Is this correct or is there something else holding the drive shaft to the motor? If it is correct and the drive shaft is simply stuck, how to I get it free?"
 
Yes the shaft should just pull

Yes the shaft should just pull out of the crankshaft splines. I reckon yours is stuck/rusted in

Also pulls out of the gearcase once the water pump is removed. Its only the impeller pin that stops it puling out of the gearcase normally. I guess you have damaged the pump/impeller housings getting it apart.

Exactly the same as my 6hp!

When you have sorted it out and are rebuilding it lightly grease the splines so that you can get it apart more easily next time.
 
Sit the outboard on its flywhe

Sit the outboard on its flywheel with the driveshaft pointing in the air and spray penetrene or wd40 onto the shaft and let it run into the driveshaft splines...the next day turn it upright and place some emery tape around the driveshaft to protect it and clamp the shaft with vise grips...use a hammer to tap on the vise grips to knock out the shaft
 
I turned the motor on the flyw

I turned the motor on the flywheel and soaked it. I was finally able to get the drive shaft loose. It came out all caked up with a bunch of rusty grime in the spline grooves. The diveshaft cleaned up nicely. I reassembled the motor and everything was looking good. It ran great in the barrel. I place the motor on my 12ft semi-v and headed to the river to boat test. The motor started fine. I put it in gear and began to slowly apply throttle. When I got to about 50% the boat was still pushing a lot of water and had not yet leveled out when I heard a bang from the motor. The prop stopped turning as well as the water pump. The engine was still running fine. The drive shaft appears to be slipping at the spline. Does the drive shaft plug directly into the crankshaft? Was all that caked up grime part of a deteriorating crankshaft? Will I need a new crankshaft? Any advise anyone?
 
Yes the drive shaft plugs dire

Yes the drive shaft plugs directly into the crankshaft.
Only inspection will reveal what has failed.
 
Jack drop the leg and check th

Jack drop the leg and check the shaft it maybe broken? but if the crankshaft splines rusted away the driveshaft splines should be full of rusty gunk etc
 
Thank you for your help. I did

Thank you for your help. I did get a bunch of rusty gunk in the drive shaft splines. I guess the next step would be to remove the top end and inspect the crankshaft. Do I need to remove the gear head first? I don't think the drive shaft broke. When I turn the prop by hand I can here a rubbing noise near where the drive shaft and crank shaft meet.
 
"[i]" Do I need to remove

"" Do I need to remove the gear head first? "

Yes I think so I found I had to rock the power-head forwards and backwards to break the joint. You need the shaft, shift rod and water tube free to do that.

You wont be able to line up the water tube when you rebuild if the gearcase is already in place, so it'll have to come off again at some stage"
 
I finaly removed the power hea

I finaly removed the power head. The crank shaft is stripped smooth. The drive shaft is a little marked up and may or may not be okay. I assume that the only thing I can do is replace the crank shaft along with the rod and main bearings. This seems like it is getting a little cost prohibitive for what the motor is worth. Is there anything that can be done that wouldn't cost more than the motor is worth? If I replaced the drive shaft along with everything else we are looking at $350.00 or more. I hate to abandon the project. The motor runs great.
 
"I 'naughty' one and n

"I 'naughty' one and not for the faint hearted is as following:
Weld the drive shaft into the crank!
Then cut it above the waterpump, grind the upper and lower ends to a square, get a similar square sleeve as 'joint' and off you go!
This is the 'cheapest' one, but no warranty!"
 
Mort nice one i have never tho

Mort nice one i have never thought about doing that but i can see it would get the motor usable again very cheaply.
 
Done it on quite a number of o

Done it on quite a number of old engines.
but as said: NO Warranty.
On the other hand I never had anyone coming back complaining!
 
There are other outboard manuf

There are other outboard manufactures who use that method to connect the upper and lower drive shafts and it worked well for the folding leg
 
"Thanks guys. Sounds like a pl

"Thanks guys. Sounds like a plan to me. I do have a couple of questions. Does the crankshaft need to be removed from the powerhead before I weld the driveshaft to it? How far in the crankshaft do I place the driveshaft when I weld? My guess would be to the oring slot. Also, I have some experience with automobile engines but I have never been into a two stroke. Do the bearings need to be coated with some kind of special lubricant before I reassemble? And is there anything else I may need to know before I get started? One other thing. When I was cleaning out what was left of the crankshaft spline I blew some air into the spline not realizing there were four holes down at the bottom. Is this how the spline gets lubrication and have I blown that grime into the crankcase?"
 
"You may not have to remove th

"You may not have to remove the crank, all depends on your welding equipment.
remove the lower seal holder, cover the lover bearing from sparks etc.
I do not recollect '4 holes' but if you post a pick it might clear up.
Just be sure the driveshaft is properly lined up before welding!!"
 
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