1957 Johnson 35 HP Starting Problems

[Mister Dave]

Alright fella's I have a 1956 35 HP Johnson that is not starting. The carburetor was rebuilt and the engine has spark. A quick shot of starter fluid will get it running and it will continue to run for a few seconds with the throttle opened all the way but then it dies. I'm at 5000' elevation in Utah. Is there any tricks with these old monsters? I have the cruise a day tank with the double lines and it seems to have good pressure. It primes fine. What could be the problem?

 

[JB]

Re: 1957 Johnson 35 HP Starting Problems

Carb is not providing fuel.

Could be a restriction in the fuel supply to the carb or air leak in the supply lines.

Could also be an unsuccessful carb service.

Go to the Top Secret file ^^^ and do "Outboard won't start".

 

[exodave]

Re: 1957 Johnson 35 HP Starting Problems

Dave, let me introduce myself: Dave. I just picked up this same engine last week and am parrelell with you in getting it running. Same problem. I have a carb kit on the way and I expect a fresh cleaning and tuning will only make things better, since who knows if the last guy knew what he was doing?

For some reason, I found that sometimes the plug where the fuel line attaches to the engine works itself a hair loose, and the fuel stops coming. What I did, was pull the fuel line off of the carb, and mess with that connection, and the primer pump until fuel was pouring from it. I was able to get the motor to idle, although too fast, that way.

I also have the coils and ignition kits coming, since I might as well have the best spark possible, just in case it's on it's last legs. So far, everything I've taken off of this thing looks original, so I'm looking to strengthen every piece I can before getting into the headache of playing with the carb. Just less frustration when you can rule everything else out, yeah?

 

[Mister Dave]

Re: 1957 Johnson 35 HP Starting Problems

Thanks guys, I will look at those things and hopefully have some success. A small motor mechanic rebuilt the carb so I will start with checking those fuel lines and mechanisms.

 

[Mister Dave]

Re: 1957 Johnson 35 HP Starting Problems

A few more questions. I should be using sae 30 oil at a 16:1 ratio, is that right? And also, can I use an sae 30 with detergents in it or should it be detergent free?

 

[JB]

Re: 1957 Johnson 35 HP Starting Problems

No, no, no!!

Use only modern TC-W3 certified outboard oil and 87 octane unleaded gas. E-10 is acceptable.

Correct fuel mix for your '57, I believe, is 20:1, but 16:1 would do no harm.

 

[Mister Dave]

Re: 1957 Johnson 35 HP Starting Problems

Thanks JB I really appreciate the response. I've been using tcw3 to try to get it started and not having any clue about these things was going to switch to sae 30 because the manual specifies it. Anyway, glad to know! I got it started this morning and I was using a 16:1 ratio but found that making it 24:1 seemed to make it run a bit smoother. It seem to be letting some of the two stroke fuel out of the exhaust why would this be?

 

[tmcalavy]

Re: 1957 Johnson 35 HP Starting Problems

Your clean carb won't feed fuel to the engine unless it's set right. You have two jets with knobs on the front...bottom is the high speed rich/lean adjustment, top is the idle circuit rich/lean. Take the cover off and loosen the lock nuts on each one, right up next to the carb...you want them just loose enough that the knobs will turn. Gently seat both knobs/jets/needles clockwise until they stop...don't get heavy handed. Back the high speed knob/jet/needle out counterclockwise about 3/4 of a full turn. Back the idle circuit knob/jet/needle out counterclockwise 1 and 1/2 half turns. That will get you in the ballpark if the carb is nice and clean. Pump up the primer bulb on the fuel line until it's firm, or prime the engine with the tank pump-up knob if you have a two-line fuel system, roll the throttle over to start, make sure its in N, pull the choke out and hit the starter switch or pull the rope. It should kick over and go on about the second or third pull. After it starts, let it run a few seconds then push the choke in/off. Run the thottle up and adjust the high speed (clockwise is lean, c-clockwise is rich) until you find the sweet spot...it should pick up noticeably as you lean it out a little. After you find the sweet spot on the high speed, tighten down the locknut. Idle it down to slow, and adjust the idle circuit jet the same way...find the smoothest running spot and then tighten the lock nut. You'll have to go through this again on the boat to fine tune it. If you run it in a barrel/tub to get the initial settings right, make sure the water level is half way up the leg or higher. If the water pump and impeller are working it will spray a bunch of water out of the large hole in the back of the leg...keep an eye on that until you're sure.