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Johnson 70hp issues

forgot to mention that when i had the lower unit off last time i noticed the water pump pickup tube going on the engine side had some damage on it. nothing crazy but how difficult is it to change out?
 
After messing with the lower unit some more I believe its bad. With the unit off and shifting by the rod itself if I put it in reverse and turn it counter clockwise it moves the driveshaft a bit if I turn it clockwise it'll pop the shift shaft up and spin. In forward gear it moves the driveshaft a bit it both directions. I found a deal on a lower unit from a 99 90hp would this be compatable?
 
Thanks for the info racer. I do have a foot from a 60hp but its the 4 spline. Would this one work if I changed the driveshaft?
 
Or if the internals would work. Im thinking its the dog clutch. Gonna get new but if i have spare gears and all that'd be awesome
 
Anyone got a good method for removing this thrust bushing? I've tried pb blaster and tapping it and some heat but its not coming off no matter what. Can't get the shaft bearing out. This part wasn't on the other lower unit.
 

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I got no luck there. I was using a 10lb that thing won't budge got kroil oil on it I've been going out every hour and putting more on. Any advice on where/how to hit to work best?
 
Used a clamp style bearing puller and it wound up bending it. Busted out the grinder and got it. I couldn't get the prop shaft out of either lower unit but I saw the reverse and clutch dog were both worn down. The gears I could see in the donor are in great shape so I changed out the driveshafts as they were the same length I've reassembled up to the snap rings waiting on the seals to get here later today.
 
I got it all back together but for some reason I cannot spin the prop shaft freely in neutral i can spin it but i have to use a good bit of force. I was able to spin it freely until I put the 4 bolts in for the prop shaft bearing. I was pretty sure I assembled it correctly and the shaft bearing carrier facing up.
 
Got it all together and tested on muffs. Have all gears no grinding at all. Hopefully get to test it on the water next weekend. But if it hadn't been answered before yeah you can use the case and internals from a 4 splined pre 88 motor all is the same except the reverse gear wouldn't go on the prop shaft as the inner diameter was slightly smaller.
 
Just took it out. Burned the impeller out somehow. I had a loud whining sound then my overheat alarm came on with smoke or steam coming from telltale. Buddy towed me back in said he could hear something whining loudly.Water was pumping when I put in and was fine on muffs. Pretty sure I installed it right. Would an impeller make a whine? I've never lost one while on water.
 
Hoping that isnt happening. I just ran it for a couple moments on muffs and no whining noise. About to pull the lower and see what went wrong.
 
Well far as the water pump goes the keyway got destroyed. Basically ground down the plastic key. Installed with the stop on the impeller facing up
 
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Just realized that one. I had the one from the donor foot its white the one that was on here was black.new one will be here Monday
 

took it out for a test run. Still has some whine. Doesn't start until half throttle. I am able to shift properly and get max speed. Does not whine on muffs. Attached is a small video of it.

Did check the oil in lower unit not really any shaving on magnet.
 

Took it out to test and its now got a knocking sound when in gear that gets worse if more throttle is applied.
 
If only. I did tear into it and found my pinion and forward gear ate up a good bit and looking closely at the inside of the case the slots where the snap rings go busted a chunk out. I believe this aluminum chunk made its way around and messed up my gears and allowed water to get by. I have a case that's the same dimension it just doesn't have the slot for an anode. No idea the year.
 

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