1968 johnson 3hp water pump replacement

maineiac5586

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Feb 14, 2009
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Hi, can someone walk me through the replacement procedure for the water pump impellor on a 2 cylinder johnson 3hp twin, 1968 model? I have done this on newer motors but I am looking for a step by step procedure (this is a direct drive motor) (no forward or reverse shift) thanks in advance.
 

1946Zephyr

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Oct 21, 2008
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Re: 1968 johnson 3hp water pump replacement

Remove the 4 bolts that secure the lower unit to the mid section and then wiggle it free. That's it. Once you get the lower unit off, you'll see a housing with 4 screws on it and the impeller is under there.
 

maineiac5586

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Feb 14, 2009
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Re: 1968 johnson 3hp water pump replacement

so, being direct drive, there is no shift linkage to deal with. iboats lists an impellor kit and a water pump kit with different part #'s. what do you think i will need as far as parts go?
 

lindy46

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Nov 27, 2008
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Re: 1968 johnson 3hp water pump replacement

Take it apart and see how the housing and plate look. If the housing is not corroded/cracked and the plate is flat/smooth and not rusted, then you probably only need the impeller. Try not to pull the driveshaft out of the gearcase when you do the job, as it can be frustrating trying to mesh it back into the pinion gear splines.
 

kbait

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Nov 13, 2007
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Re: 1968 johnson 3hp water pump replacement

Lindy speaks truth! I had to drain/disassemble one as I could not get it re-aligned. The good part is that there is nothing in this life simpler than a 3hp gearcase!
 

1946Zephyr

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Re: 1968 johnson 3hp water pump replacement

Yea, you don't want to pull the drive shaft. I have on one, but fortunately, I lined things back up easily enough and didn't have an issue, but from what I see, the pinion gear will be able to move around feely, if the drive shaft comes out.:eek:
 

HighTrim

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Jun 21, 2007
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Re: 1968 johnson 3hp water pump replacement

If that drive shaft does come out.....a little trick I heard about, is to hold onto it with the prop shaft pointing down. Front of gearcase pointing UP so pinion gear will fall back down into place. Turn prop shaft back and forth a tiny bit while dropping drive shaft back into the pinion gear.

It is a bit tedious, be it should go. Quicker than taking it all apart.
 
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