Update on 1957 Johnson 18 HP fuel pump conversion.

[bplayer405]

I went through a lot with this motor over the last month so I thought I'd post an update. I converted the two line fuel system to a single line. I used a Minuki style snowmobile fuel pump that runs off the same pressure port on the intake that used to pressurize the old tank. I removed the check valves from the reed plate and plugged one check valve port to give the fuel pump its pulse signal. I realize there was another way to do it that is easier; porting one of the side covers for the pulse and plugging off the pressure port. Anyway, after having a slipping prop hub and a fuel line that the inside liner was collapsing {now a new prop and all hoses replaced also replaced the upper crank seal}, the motor runs perfect! This little motor pushes my 1648 ex wide and deep fully decked jon around 20mph! All that said, doing the fuel pump conversion was definately worth the effort!

 

[kodibass]

Re: Update on 1957 Johnson 18 HP fuel pump conversion.

Thanks for the update, I'M doing a 58 18 HP right now, It is electric start & choke so I'm finding it hard to find a place for the fuel pump. I am using a minkuni pump I tapped the bypass for pulse. The hardest part seems to be routing the hoses. Glad yours came out so well.

 

[bplayer405]

Re: Update on 1957 Johnson 18 HP fuel pump conversion.

On my 57 there's two threaded holes above the carb that's spread out pretty far just below the pull starter and on the brackets it mounts to. I mounted the pump to one of these holes then ran zip ties through the other and back to the pump. Was gonna make an aluminum bracket, but opted for the zip ties for now.

 

[kodibass]

Re: Update on 1957 Johnson 18 HP fuel pump conversion.

i'll have to give it a look see this weekend, i will get back to it in the next few days.

 

[kfa4303]

Re: Update on 1957 Johnson 18 HP fuel pump conversion.

Congratulations bplayer! The '57 models are some of the best looking OMC motors and the 18hp are probably the strongest pound-for-pound motors ever made. Happy boatingg. Vroom-vroom!!!!

 

[Crosbyman]

install a single line connector on the side of the motor and plug the pulse port behind/below the carb