1975 Johnson Carb Removal

OLDIRON

Petty Officer 2nd Class
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Apr 2, 2008
Messages
135
Hi all,I just joined,but I have been lurking,and learning.Great forum by the way. So here's the scoot...A friend of mine gave me a 15r75c Johnson.It was in pretty good shape cosmeticly, and free, so I didn't mind dumping some dough into it.The spark coils were rusty and swollen,so I replaced them,along with new points, plugs, and impeller.She's got good fire now,and compression is approx.100# in each jug.She runs good, but she just dosn't want to idle very well.So I'm thinking my next step is fuel.This motor hadn't seen water for atleast 10 years. I bought a kit to rebuild the carb, which I havn't installed yet. So here's my question.....is there any way to get the carb off without removing the recoil starter?Any tricks?That recoil unit intimidates the bejezus out of me,and I don't want to remove it unless I absolutly have to.I've had the flywheel off before,but it looks like that will still not give me enough room to get the carb off.Thanks for any help.
 

iwombat

Captain
Joined
Jul 12, 2006
Messages
3,767
Re: 1975 Johnson Carb Removal

You gotta remove it. What I do is remove the bolts that fasten it into the bracket, then push it out of the way and use masking tape to keep it from wondering around. That way it stays in it's bottom mounting point. At least, that's what you could do with the 80s models. Your mileage may vary.
 

OLDIRON

Petty Officer 2nd Class
Joined
Apr 2, 2008
Messages
135
Re: 1975 Johnson Carb Removal

You gotta remove it. What I do is remove the bolts that fasten it into the bracket, then push it out of the way and use masking tape to keep it from wondering around. That way it stays in it's bottom mounting point. At least, that's what you could do with the 80s models. Your mileage may vary.

Thanks,I kinda figured that would be the case.Oh well ,I'll get her done this weekend.
 

OLDIRON

Petty Officer 2nd Class
Joined
Apr 2, 2008
Messages
135
Re: 1975 Johnson Carb Removal

OK,I got the carb off.The recoil was not as bad as I expected.It was held on by one bolt,which I didn't take all the way out. I didn't even have to take the flywheel off.Just put a 3/8" nut on the bolt to hold everything together,and hung it out of the way.Now the question.There is a small white thing that came in the kit.I believe from the blow-ups of the carb,it is called a bearing/needle valve , part # 0314166. It looks like it goes at the very end of the rich/lean adjustment needle valve, deep into the threads. How the heck do I put that in? And just as importantly,how do I get the old one out?Can anyone help me figure this out? Thanks.Oh,and one more question if I may.Float adjustment.Do I just turn the carb upside down ,and set the float level,there is no gage in the kit, like a car kit that I'm use to.Thanks again.
 

OptsyEagle

Lieutenant
Joined
Sep 13, 2006
Messages
1,356
Re: 1975 Johnson Carb Removal

This may not be the recommended method but I just used a #8 deck screw and screwed it in ever so lightly (not wanting to go too deep into the carb itself) until I got a bite on it and could pull it out. It is just plastic of some sort.

I can't remember what I used to put the new one in but it would have been something solid that was about the same diameter and it worked well.
 

OLDIRON

Petty Officer 2nd Class
Joined
Apr 2, 2008
Messages
135
Re: 1975 Johnson Carb Removal

That does sound like a reasonable method.THe problem is ,I really can't see if indeed,there is an old one in there. With a bright light,I can see what looks like a discolored thing down in there.If I were to assume the carb has never been messed with,it should be in there.But what if someone has been in there before, and left it out? I don't want to bugger the taper for the needle valve.
Alas, this is a delema.Thanks.
 

OptsyEagle

Lieutenant
Joined
Sep 13, 2006
Messages
1,356
Re: 1975 Johnson Carb Removal

Yes. I know what you mean, but that is why I said "ever so lightly" turn the screw and when you go in a millimetre or so, give it a light pull.

I would bet there is one in there. The factory would have put one in and anyone else that took the agonizing time to get that factory one out, would most likely really want to put a new one in there. But alas ... some people are not that bright, so there is always a slim chance it is not in there and yes, that steel screw is not going to be nice to that carb if it ends up bottoming out on it.

I had the same issue as you (actually I have the same motor as you) and made my bet and ended up pulling that piece out. That's my thoughts on it. Good luck to you.
 

OLDIRON

Petty Officer 2nd Class
Joined
Apr 2, 2008
Messages
135
Re: 1975 Johnson Carb Removal

Yes. I know what you mean, but that is why I said "ever so lightly" turn the screw and when you go in a millimetre or so, give it a light pull.

I would bet there is one in there. The factory would have put one in and anyone else that took the agonizing time to get that factory one out, would most likely really want to put a new one in there. But alas ... some people are not that bright, so there is always a slim chance it is not in there and yes, that steel screw is not going to be nice to that carb if it ends up bottoming out on it.

I had the same issue as you (actually I have the same motor as you) and made my bet and ended up pulling that piece out. That's my thoughts on it. Good luck to you.

Well, I took your advice and put a long drywall screw down there, everso gently, gave it a turn, and out came the bushing, what's left of it. Man, you are good! I"ve worked on alot of different motors, but I would have never thought of that. As far as getting it in,I just put it on the needle valve, and it seats itself when I screwed the needle in. I should have it running again today.Thank you very much!
 

OLDIRON

Petty Officer 2nd Class
Joined
Apr 2, 2008
Messages
135
Re: 1975 Johnson Carb Removal

Just wanted to give you an update.The carb overhaul went great.I belong to a car forum, and what kinda bugs me is after somebody starts a thread about a project,and asks questions,they don't say how it turned out.It leaves you wondering if their problem got solved.Well, thanks to you all,mine turned out perfect.She runs like a new motor.I feel like with your help, I've accomplished something. I saved a 33 year old motor from the scrap heap,and brought it back to life. It's a little much for my 10' Zodiac.My 5hp Merc/Tohatsu scoots it along pretty well, but I'm gonna try it out next weekend at Tomales Bay, just for fun.Hey, this could be an excuse to get a bigger boat!!!
 
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