1962 Johnson Impeller

[daveydb]

Hey I was just wondering if there is a trick to replacing the impeller on a 1962 Johnson 75 hp outboard. I have never changed an impeller but would like to do this one myself. If anyone can shed some light on how to do this that would be great. I was just wondering if there is something that needs to be done with the driveshaft. Also, since it is electronic shift, is there electrical that I need to worry about?

Also, if I wanted to replace the lower unit seals, would most marine shops have the tools to do this? I am wondering this because they want to charge me a ton because the parts are so ancient, but if I could purchase them online I was wondering if it would be easy for them to change those seals. Thanks for all of your help on this forum.

Dave

 

[F_R]

Re: 1962 Johnson Impeller

The electric shift wire has to be disconnected, then the plate taken off the side of the midsection and then the other plate inside there. Pull that second plate off the wire. Then you can remove and work on the lower unit and seals. The drive shaft seal is easy. The prop shaft seal may be easy or nearly impossible, depending on whether you can see it when you remove the prop. The one you can't see, you need a special tool to remove the bearing from the gearcase head, then you have to replace the bearing with a new one, along with the seal. I get around that situation with a little creative re-engineering with my metal lathe.

If that's as far as you go, you should be OK. Getting deeper into the gearcase is far more complicated and special tools are involved.

 

[daveydb]

Re: 1962 Johnson Impeller

So do you disconnect the electric shift wire by taking the plate off or is that something else? Also, do you have to mark the driveshaft or anything so that it goes back together the correct way? Thanks for the reply.

Dave

 

[F_R]

Re: 1962 Johnson Impeller

The disconnect is at the rear of the powerhead, near the black plastic thermostat housing. It is two wires, green and blue, covered with rubber sleeves. Slide the sleeves aside and you will find knife-disconnect terminals.

It's advisable to tie a string or something to them before removing the lower unit. The string is to get them back up in there when reinstalling. No other sneaky tricks come to mind.

 

[daveydb]

Re: 1962 Johnson Impeller

Thanks for the replies. I have a couple of pictures to make sure I am doing it right. The first one shows a wire that is going down to the lower unit. Is that the one that you disconnect?

In the second picture, is the plate you take off to disconnect the wire at the water intake, or is it up above what this picture shows. There is some red/pink sealant stuff and I was wondering if it can be purchased somewhere so that I can seal the plate back when I am done. Also, is the water cooling outlet the hole in the upper left or is that down near the prop?

In the third pic, the seal at the bottom is leaking and I was wondering if this is one that is doable by a novice or not. Thanks for all of your help. Sorry for the lack of termonology. I wish I could find someone around here that would work on this but I am having fun learning.

 

[F_R]

Re: 1962 Johnson Impeller

1st picture, yes that is the wire. Somebody has covered it with a funky looking tube. What is that unidentified object fastened to the thermostat housing?

2nd picture, No that is not the plate. Look several inches above where it says Super Quit. The one you are looking for is a couple of inches diamond shaped with 2 screws. Pink sealant?? Don't know what you are referring to.

3rd picture. Take the propeller off and see whether you can see the brass seal around the shaft. If you can, the seal is replaceable with some coaching. If you can't see the brass, it takes a special tool and you may destroy the bearing to get it out, even with the tool.

Where is "around here"?

 

[daveydb]

Re: 1962 Johnson Impeller

Around here is in Lehi, Utah. Is the unidentified object you are talking about the round tube that is sticking up from where the wire is held down? I have no idea what it is.

I found the diamond shaped plate you are talking about. So, I take that off and then another plate under that. Does the inside plate come off the wire? After that is off, then we can drop the lower unit?

The pink sealant that I am talking about looks like silicone but it is pink and is everywhere there should be a seal. The diamond shaped plate has it around it and the any of the seams that are bolted together.

I was also wondering which bolts I undo to drop the lower unit. I was thinking it is the lower ones and not the ones that are under the Super Quiet logo. Is that right? The driveshaft should disengage and it should come right off, is that right? Then we just unscrew the water pump housing and replace the impeller? Then do the reverse and we are good?

I don't know if the pink sealant stuff is just something the previous owner used or what. Should I get seals or anything to replace when putting it all back together? Does the lower unit need to be drained before lowering it?

Thanks for all your help. I owe you one.

Dave

 

[Evinrude Boater]

Re: 1962 Johnson Impeller

Remove the lower set of bolts to drop the lower unit. The water pump will be exposed on top when you pull the lower unit off. No need to mark the drive shaft. It is spline shaft and will realign easily when you reinstall. You should inspect the water pump plate and housing and determine if it is worn or pitted too much to use. If it's in good condition you can just order an impeller repair kit instead of the water pump assembly.
If the gear case oil is milky then you've got a leak. You can pump about 7-10 psi air into the drained gear case and dunk it in a bucket of water to find the leak or just replace all the seals. They're not hard to replace but most shops don't want to work on something so old.

 

[F_R]

Re: 1962 Johnson Impeller

The former owner got a tube of pink glop for Christmas and had to use it on something. Probably glued the toilet seat down with it too.

 

[daveydb]

Re: 1962 Johnson Impeller

I have a new impeller but it doesn't have anything else with it. Do I need a "repair kit" to do that or can I just replace the impeller and be good?

 

[daveydb]

Re: 1962 Johnson Impeller

Actually, I just looked in the marine store on here and couldn't find a repair kit for the impeller or water pump for a 1962 75 hp Johnson so I guess it is going to have to do. Any seals that need to be replaced afterward?