1950's Johnson 3 HP

[tedstur]

I just finished putting in a rebuilt kit on a carb for this old motor. I put it back together and she started on the 2nd pull! However, I then noticed gas dripping from the carb. I shut it off and it leaks as soon as I open up the gas tank vent and open up the gas line. I have studied it and can't quite see where to start on determining where the gas is coming from. It flows out the carb pretty unimpeded.

Before I took it off and started messing up what I had just put back together - can anybody tell me what I might want to look for?

 

[bktheking]

Re: 1950's Johnson 3 HP

Float sounds like its not set at the right height or it wasn't assembled properly causing the float to hang up.

 

[tedstur]

Re: 1950's Johnson 3 HP

Thanks, that makes perfect sense. I will pull it and look.

 

[tx1961whaler]

Re: 1950's Johnson 3 HP

The float is stuck, or sunk. If it's a cork one, make sure it still floats in gas.

 

[1946Zephyr]

Re: 1950's Johnson 3 HP

most carb kits I've seen come with a new float.

 

[tx1961whaler]

Re: 1950's Johnson 3 HP

most carb kits I've seen come with a new float.

The OEM ones do; the Sierra ones don't.

 

[1946Zephyr]

Re: 1950's Johnson 3 HP

Yea, I was about to say, I just rebuilt a carb on a 1958 3hp and of course, I only buy OEM parts for my stuff. I would stay away from Sierra as much as possible. Simply because their stuff doesn't match OEM as much as it should.

 

[BigB9000]

Re: 1950's Johnson 3 HP

Simply because their stuff doesn't match OEM as much as it should.

A big +1 on that.

I ordered a carb kit for the 6hp from serria, then went ahead and ordered the right parts from shop.evinrude

 

[tedstur]

Re: 1950's Johnson 3 HP

My kit didn't come with the float.

I appreciate the advice I got here. I took the bowl off to discover that I neglected to put the spring on the float pin! Put it on and bingo! The motor is running well. It's very smooth at medium to fast speeds, and tends to run a bit rougher on the slow speed. This motor sat for 17 years, so perhaps it will take a few tanks of gas run through it before it smooths out.

It is a '54 JW-10 and I will be using it on my 16 foot sailboat.

 

[bktheking]

Re: 1950's Johnson 3 HP

If the idle bothers you, take the carb off and soak the carb again, overnight.

 

[1946Zephyr]

Re: 1950's Johnson 3 HP

A big +1 on that.

I ordered a carb kit for the 6hp from serria, then went ahead and ordered the right parts from shop.evinrude

Yea, I read a thread here just over a month ago, where a guy had trouble with a Sierra water pump on his 3hp. The vanes were so big that his motor died tryin to turn the darned thing. Unfortunately, I have a hard time trusting what I buy at Napa. I've had pretty good luck with stuff at Vintage outboard though.

 

[tmcalavy]

Re: 1950's Johnson 3 HP

Ditto...pull and re-soak the carb, put it back on and run some Sea Foam through the next tank of gas...bet the idle smooths out after that.