1995 johnson 50hp carb/fuel questions

[MASTERBrian]

Recently bought this 1990 bass buggy pontoon with this engine on it. Being add it say for several years and was running poorly I decided to rebuild the carbs add a starting point. I have a few questions. ....

1) the guide that came with the carb kit says to turn the low speed screw lightly in and then back out one turn. Easy enough, but when I checked against the carb I hadn't touched the screw on that one was two turns out. Which should I do? Am I correct in thinking this is the idle, so if it idles poorly just turn then both out?

2) on the fuel pump there is a 2nd line going back to where the hose coming from the tank connects to the lower shroud. It's the bottom hose. The tank is connected with a single hose so the bottom one is blocked off outside the shroud. Am I correct in thinking this is a return line and not needed?

3) there is a set of wires coming off the fuel pump going to a connection.... that connection isn't hooked up. Any ideas..... should it be?

I don't have a manual for this motor, but I have one for up to 1990. The engine looks very similar,except smaller than my xp150. I'll look into some of this some more tomorrow, just getting it off brain for tonight....

Thanks for any guidance!

 

[Daviet]

Re: 1995 johnson 50hp carb/fuel questions

You didn't list a model number, but maybe I can help.
1) The guide just gives you a static setting for the low speed needle, you will have to fine tune the carbs in the water, in gear and the proper idle speed set.
2&3) Are you running premix or is the VRO hooked up? It sounds like some one has eliminated the oil side of the VRO pump.

 

[MASTERBrian]

Re: 1995 johnson 50hp carb/fuel questions

Is the carb adjustment something that can be done with engine setting in a tank?
As for 2&3, yes it's premix, that makes since. .... wonder why that didn't click!
On that note, is there an easy way to tell if the vro pump works? I'd love to be able to go with oil injection. ...
I'll run to post model # in a while.

 

[Daviet]

Re: 1995 johnson 50hp carb/fuel questions

You can static set the low speed adjustment in a tank, but to fine tune it you need to have the boat in the water and in gear.
My thoughts on VRO, leave it disconnected and run premix.

 

[MASTERBrian]

Re: 1995 johnson 50hp carb/fuel questions

You can static set the low speed adjustment in a tank, but to fine tune it you need to have the boat in the water and in gear.
My thoughts on VRO, leave it disconnected and run premix.

I've been trying to research this a bit. Please correct me if I'm wrong...

To static set the carb, I want to warm up the engine and then set it to a high idle? Then adjust the carbs in or out until it reaches a nice idle?

As for boat being in water and in gear, without sounding ignorant....what's the best way to do this? Hooked to the trailer or actually out in the water moving around? My guess is the idea is to get the boat under load. I just don't know if the trailer is enough to do this. The other problem I have is being on a pontoon, I can't really reach the motor from the boat itself and I'm not really fond of the idea of standing next to an in gear boat trying to adjust a carb....I am still rather fond of my legs and feet!! If the goal is to get a nice even idle, is this something that can be accomplished with the boat underway, seeing how it is running, then shutting it down, making a small adjustment and then going again....repeat, repeat, repeat....

Again, hope that doesn't sound ignorant, on my other boat, it would be no issue at all leaning off the back with the boat underway tuning it, but on this one, I'd have to have my feet strapped to the railing and then I'd have to hang down about 3' to get to the motor which is about 1-2' back from the rail. Hmm!!

Oh, and I finally got the model #J50TLEOD.

Thanks again for the help!

 

[Daviet]

Re: 1995 johnson 50hp carb/fuel questions

I think the static setting on your carbs would be 2 1/2 turns out from lightly seated, no need to have engine running.
To set it properly you will have to have the boat in the water. The way I do it is to have somene run the boat in gear and turn the low speed needle 1/8 turn at a time, in or out, until I get the best and smoothest idle. This can be a long process with duel carbs, but it has to be done to get the best idle. Once you get the carbs adjusted properly, check the idle speed, should be 700-750 in gear when warmed up.
Pontoons can be a challenge because of the way they are made.