10hp Johnson.

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Re: 10hp Johnson.

Postby Mumbles » Thu May 17, 2018 1:21 am

Anything can be done. About fifteen years ago I mounted a small fuel pump on the side of the crankcase of a '57 Evinrude 7.5 horse Fleetwin which does have bypass covers. This way it looked neat and you could swear it came from the factory with the pump. I used aluminum tubing threaded and epoxied to the crankcase and it hasn't fallen off or dropped any pieces into the motor yet (knock knock). Unfortunately I don't have any photos of it but I should pull the motor out and take some the next time I'm over at my storage place.

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Re: 10hp Johnson.

Postby crosbyman » Thu May 17, 2018 6:58 am

bobw wrote:I'm still relatively new at restoring these old motors and like that line in one of Clint Eastwood's old Dirty Harry movies, "a man's got to know his limitations". I know I'm not ready yet to attempt that kind of conversion but it sure sounds interesting.

I did it it....you can but first....locate a single line side connector

the plate over the bypass is easy to do ....but do drill a hole in the bypass cover to allow pulse waves to reach the pump over the cover

don't forget if you do not use the pressure nipple method behind the carb just plug it with a piece of one inch rubber hose and plug it with a short bolt with a tye wrap

https://www.youtube.com/watch?v=FtG4M7ye1N8 this method is ok but pump over the bypass cover is the best way to go (just my opinion) ...if you can not locate a spare cover ready made to accept the pump.

just cut up some aluminum plate, line up the holes drill & mount . make up a gasket install as shown between the cover and the plate
5.5 Hp Dec 2013 018.jpg
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fd-10 mods 001.jpg
fd-10 mods 001.jpg (149.49 KiB) Viewed 272 times
5.5 Hp Dec 2013 019.jpg
5.5 Hp Dec 2013 019.jpg (907.39 KiB) Viewed 272 times

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Steve A W
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Re: 10hp Johnson.

Postby Steve A W » Thu May 17, 2018 9:05 pm

Or put an ad on the classifieds for a usable tank and leave the motor original.

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Re: 10hp Johnson.

Postby kirkp » Fri May 18, 2018 8:52 am

Bob, where are you located? Saw a ad on CL in Iowa where a guy has about 25 pressure tanks for sale. Asking like $30 each.

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Re: 10hp Johnson.

Postby bobw » Fri May 18, 2018 9:14 am

I'm in Rockport, TX so it would be a bit of drive to Iowa. Sounds like a good price for those tanks though.
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1954 Johnson CD-11
1958 Johnson QD-19
1972 Evinrude 25202

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Re: 10hp Johnson.

Postby OLCAH » Fri May 18, 2018 2:09 pm

My 2 cents - If you get one good pressure tank it will fit a bunch of Johnson/Evinrudes from the 1950s. That way you do not have to convert every time you get a pressure tank motor. I see no particular advantage to converting unless you want to use the same tank as another non pressure motor. Seems to my simple mind that it just adds complexity, something else to fail. Pressure tanks are the original deal, They look old school. They work just fine, parts are around and to me it is the easy way to go.

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Re: 10hp Johnson.

Postby Chinewalker » Fri May 18, 2018 2:13 pm

Another advantage to leaving them original – you'll never mix up the wrong fuel tank with your motor and run it at 50:1. Those 10s are very susceptible to wrist pin bearing failure on the con rods, made worse when folks run them lean on oil. If you have pressure tanks always mixed to 24:1 or richer, you won't have to worry about it.

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