1971 Johnson 9.5hp Overhaul

[bnow0707]

I'm rebuilding my grandfather's '71 johnson. It hasn't been ran in years but I've gotten it running. Now I need to know what parts need to be replaced/inspected before i run it for extended length of time. I replaced the fuel lines, fuel pump, fuel pump gasket, and lower unit oil. I'm planning on replacing the water impeller, anything else?

 

[DJ]

Re: 1971 Johnson 9.5hp Overhaul

Points/condensers and probably ignition coils. All are under the flywheel.

I would rebuild the carburetor too.

All the parts are avialable here on iboats.

Other than that, it will be like NEW!

 

[mchin]

Re: 1971 Johnson 9.5hp Overhaul

not sure how far ya wanna go with this, but if you start to experience the engine cutting or running rough, especially when running in a barrel, you may need to replace the lower boot gasket, this is a pain to get to but if you are removing the side cowls and the whole 9 yards, then you'll be half way there. One other thing to consider is replacing the rubber cushions that keep the motor from shaking too much. these too dry out or harden. you'll know if you need to replace them if your motor shakes so much, it won't run well.

Have fun and post some pictures when you're done.

 

[jeff_smith_0423]

Re: 1971 Johnson 9.5hp Overhaul

Agree about the motor mounts and rubber exhaust boot - those decisions you can make after you've been through the ignition and the carb. Ignition parts are cheap and available here. The carb kit, you'll need to get from BRP or an Evinrude dealer - it's sort of spendy but includes the float as well. I haven't been able to find an aftermarket equivalent. Get an original service manual from Ken Cook and pay close attention to the throttle linkage when you're removing the flywheel and armature plate.

 

[bnow0707]

Re: 1971 Johnson 9.5hp Overhaul

Thanks i'll look into getting those parts. As of now I've dropped the l/u and I'm in the process of replacing the water impeller. The problem i've run into is which way do the vains on the rubber impeller go? The vains on the impeller that was on the motor are turned a different direction than the vains in the diagram(from BRP parts catalog) in the picture below. Are they self correcting or are they required to be installed properly?

 

[Rick.]

Re: 1971 Johnson 9.5hp Overhaul

The easiest way to get then vanes right is to look at the direction the flywheel turns and the impeller will turn the same direction so the vanes will follow the direction of turn. I would think they will self right themselves but I have no evidence of it. Best to get it right yourself. Rick.

 

[bnow0707]

Re: 1971 Johnson 9.5hp Overhaul

Yeah thanks. I found in another thread that the shaft should turn clockwise(and it does) so i mounted the impeller and housing and turned the shaft clock wise while applying slight pressure to the housing and it fit in. Tested it in the water tub and it works fine. Taking it to the river tomorrow to see how it runs in open water and to see how it will push my 14 ft john boat.

 

[mchin]

Re: 1971 Johnson 9.5hp Overhaul

cool, let us know how it goes!

 

[John Lapic]

Re: 1971 Johnson 9.5hp Overhaul

DJ suggests replacing the coils may be in order. Is there a way to test coils? Seems to me if I am getting a good spark, coils should be OK. How can I tell if I need new ones?

 

[iwombat]

Re: 1971 Johnson 9.5hp Overhaul

Pop the flywheel and look. If they appear cracked or just plain nasty they'll need replacing. And, if they're original it's about 99% likely that they'll look very much like they need replacing.

Don't worry too much if you have exhaust problems running that motor in a barrel. It sits so low to the water, that it generally will even if all the exhaust seals are correctly functioning. Exhaust issues on the boat is a whole different matter.