How to change water pump impellor on 1968 Johnson 20 hp

[viciousfishes]

I need to change the impellor before this impellor makes me change motors. Its been pounded by the pluff mud and saltwater of Charlston and it miraculous that the impellor has lasted this long. Anybody know how hard of a job this is and what all do you have to take off?

And has anybody else noticed the Johnson/Evinrude forum has more then twice as many posts as the next outboard brand on the page where you select your forum topic?

 

[samo_ott]

Re: How to change water pump impellor on 1968 Johnson 20 hp

Yes, this is a very active forum. They're great engines

It's easy to change your impeller if you're mechanically inclined at all. If you have a lot of mud and silt, you probably should consider changing the housing also.

First remove the oval cover halfway down the leg (2 small slotted screws). Inside is the shift linkage, completely remove the lower screw (and dont drop it down the housing! The remove the 4 smaller bolts on the LU from underneath and the one larger one on top. The LU will now drop off. Don't drop it. The there's 3 or 4 small screws on the pump housing, remove it and there's the impeller to replace. Reverse to install. And most importantly ensure the water tube is in the top of the water pump housing when you re-install. Post other questions if you have em. I have a '66 J20. and the parts manual (which is really close to yours). If you want it send me a PM with your email.

 

[viciousfishes]

Re: How to change water pump impellor on 1968 Johnson 20 hp

Thanks so much! Those were very detailed directions and that doesnt sound bad at all. I just wanted to make sure it didnt have any suprises for me when I started taking it apart like my fuel pump did. And I will send you a message with my email.

Thanks again

 

[viciousfishes]

Re: How to change water pump impellor on 1968 Johnson 20 hp

Ive got another question for you.

I need a new propellor and I was looking around on this website for a new one and they have a good selection for a decent price. Do you know if a prop from a 20 hp 69 would fit on my 20 hp 68? The years thet have say from 1969-1973. Also, would I be better off with a 7, 9, 10, or 11 inch pitch prop?

Here is the selection of props I was looking at: http://boatpropellers.iboats.com/Jo...r=1972&**********=797232832&*******=064602590

 

[wilde1j]

Re: How to change water pump impellor on 1968 Johnson 20 hp

See here for water pump info:

http://forums.iboats.com/showthread.php?t=299680