Johnson 70 water pump change. Can't remove impeller

salmonchaser20

Recruit
Joined
Sep 27, 2003
Messages
1
Thanks for any help. 1980 something johnson 70 stopped spitting water. I have read many other posts on this and changing the water pump, but haven't seen anyone mention if removing the impeller is tricky. Got the lower unit off and removed the housing, but the impeller seems fixed to the d/s. The manual doesn't address this. I also question if this is my problem as the impeller seems to be in good shape, but plan to replace the pump anyway as this seems to be the advice in many, many posts.
 

ezeke

Supreme Mariner
Joined
Sep 19, 2003
Messages
12,532
Re: Johnson 70 water pump change. Can't remove impeller

Had to cut one off once because it had corroded and stuck. One of the reason many of these are changed periodically is to avoid that.<br /> <br />You can take your chances with the one that looks okay, but eventually you will want or need to get under it. You can try a solvent to loosen it, but if it is galvanic corrosion you will probably have to cut because the metals will have fused. <br /><br />If you look down the impeller, you can see the slot where the pin fits. That is where you want to cut so that you don't damage the drive shaft.<br /> <br />Using a sacrificial anode will help to slow this kind of problem in an outboard motor.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Johnson 70 water pump change. Can't remove impeller

hello<br /> its called brass on stainless and it is corroded to the shaft. find the impeller key slot and using a medium chisel that is very sharp lay the chisel parellel to the shaft and cut the hub. use a 24-32 oz hammer so it can be done in a few sharp blows<br /> good luck
 

R.Johnson

Rear Admiral
Joined
Sep 24, 2003
Messages
4,446
Re: Johnson 70 water pump change. Can't remove impeller

This impeller is held by a wedge shaped nylon key. Hold the impeller with a pair of chanel lock pliers, and turn the drive shaft counter-clock wise to break the bond.
 

P.V.

Chief Petty Officer
Joined
Mar 14, 2002
Messages
452
Re: Johnson 70 water pump change. Can't remove impeller

Yes, it's wedged on by a small plastic "key". As the shaft is rotated, it wedges itself on tighter and tighter. So.... do this, take a fairly large screwdriver and hammer. Rap the heck out of the impellor the opposite way it normally rotates. The screwdriver will damage the impellor but a wack or two will help break the tension. Have a penerating oil on the shaft earlier and then use two screwdrivers to pry up the impellor from both sides. It will come in short order!!
 
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