Trying to rebuild 18 hp Johnson

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HighTrim

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Re: Trying to rebuild 18 hp Johnson

SOrry Im not real sure on this one. There was no mid year change that I know of regarding gear sets. Can you post a link to the ad you are inquiring about?
 

samo_ott

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Re: Trying to rebuild 18 hp Johnson

I have seen both size gears and believe if you change the 3 together you are ok. (I might actually have done it once but dont recall for sure) But maybe someone else will know for sure.
 

ccvolsdhf

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Re: Trying to rebuild 18 hp Johnson

Thanks guys...HT here's a link. The first 2 you have to click on to see the pic's. These 2 are what my gears look like. The problem is these are the only ones I found like that. If I bought this one I would then only need the rev gear as I believe my pinion of this size is ok. But last I looked I couldn't find the rev (307125) gear with that many teeth. With the exception that maybe marineengine's could be like mine (they have no pics),and there's are by far the most expensive. The 3rd one listed in link is what's all over ebay. I could get a set of for,rev,and pinion for under 50 bucks.

http://www.vintageoutboardparts.com/shop/index.php?main_page=advanced_search_result&search_in_description=1&keyword=+377876

One thing I just noticed in the parts book It list the gears separate as parts 377876 and 307125 and says for model fd-13r.
Then it list them as a set(For,rev,and pinion) as 377877 for model FD-13 only. My model is FD-13. So with this number at marinengines it is something else. As they only want 75$ for it and they call it (Vtg. head & brg assy). And with that number (377877) in ebay it does bring up a gear set,but its of the larger teeth. not the same as mine. So yeah I'm at a loss here.:confused:
 

AlTn

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Re: Trying to rebuild 18 hp Johnson

no question the dog is shot..that's outta the way...matched 20 tooth gear set?..if they'll fit in the gear case...good to go, but you'll probably have to go with a 9" prop to make up the rpm's..just looking at how fwd gear and its bushing fit.. it looks to me that if the gear is any "thicker" it and the prop shaft won't rest in the gear housing...any way to acquire a measurement before purchase?
 

kfa4303

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Re: Trying to rebuild 18 hp Johnson

I'm not aware of any mid year gear change either and I think AlTn is right. If the gears fit, they should work. I'm not sure of the tooth count on my '66 20 hp, but I do run a 9 x 9 prop per Altn's post, and I get about 20 + mph on a 14' tinny. Seems to work pretty well all and all. I might be able to get a bit more if I fiddled with the prop, etc..., but I'm happy with it as it is. You may also want to check aomci.org for a gear set, or some clarification on a gear swap issue. Good luck. Keep use posted. We wanna see that old 18 zooming ASAP ;) The water is calling. It was almost 90 degrees down here yesterday.....in March !!!!
 

AlTn

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Re: Trying to rebuild 18 hp Johnson

yeah, the white bass < locally refered to as stripe > are starting to show up for the Spring spawn here...water temps 54 degs. or so
 

ccvolsdhf

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Re: Trying to rebuild 18 hp Johnson

Hey guys... Well looks like the PO had installed a gear set from another yr or hp possibly 15 or 20 hp motor. This from a vary nice lady at Vintageoutboardparts.com. Who buy the way just called me back today after receiving my phone call yesterday. So apparently operating on SAT and SUN with let me look into this and get back to you service. Something I'm sure not found often especially on SUN!. So for her due diligence I am recommending you guys check them out if in need of some parts. They seem to have a large assortment of stuff. With her suggestion that I have the wrong gears for my motor. And after a little thought I'm thinking that fits pretty well to my problem of seeming as if the linkage was off. As the 21 teeth gears are different outside diameter then my 26 teeth gears which it seems would have pushed the linkage out of whack. So I'm ordering new gear set fwrd,rev,and pinion. Will have to get the dog next week.

Now for the other problem(water in the LU) here's my question. Is there supposed to be a small hole in the water tube. When I got the tube from marine engines I saw a small hole in it clearly made with a drill bit. So while it seemed odd I figured it surely was supposed to be there, and figured I would ask you guys about it. then totally forgot about it till just now.
 

Jim1979

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Ccvolsdhr, this thread is great! I inherited my fathers wooden skeeter bass boat with a 18hp Johnson sea horse after he passed away. Iv been attempting to reseal and rebuild it and have been stumped. I started pulling seals and then panicked when I started trying to pull them and was splitting brass! And thinking I just destroyed something that is irreplaceable! But I found this forum and all your pictures and info and now I can sleep at night! Thank you. I have pulled all my seals successfully. And purchased a sierra kit 18-2684. 2 questions for you? My kit does not contain orings for the top of the driveshaft by spline and the same for shift shaft. I have dug around for schematics on Internet and parts lists, found a few veague ones massed together for multiple years. Also when you installed your prop shaft seal did you stack 2 as well, I have almost enough space to do that, the old ones came out backwards, should the new one be put in that way? And I think my spaghetti seal is to small it is red not black that came in kit. I'll try to post some pics as well. You have helped me out so much more than you know, thanks again!!!
 

Tim Frank

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This is a two year old post.
If you would like answers to your questions, you'll have better luck and results starting your own new post....as per the forum rules. :)
 

GA_Boater

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This topic is closed for posting. Use it for reference. :closed_2:
 
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