Looking for info

[westay]

Just before the lakes iced over last year I bought a 1954 Sears 13 1/2 foot aluminum boat. It came with a 10 hp Johnson 2 cylinder 2 stroke motor also from 1954 and a 1954 6 gal gas tank.

The motor is clean and appears to be in good shape. I get spark. The carburator is clean and the two jets are as well. My problem appears to be in getting the gas from the tank to the carburator. The hose setup is a two line with one fuel and one air. The hoses aren't blocked and the tank appears to be pressurizing when you press the pressure button many times.

Anyone have any experience with old two stroke engines that has any advise I would appreciate it.

[UtahFlyGuy]

You didnt mention anything about a choke. Did you locate it?

[westay]

Yes, I've cranked with the choke open and closed. The butterfly works fine.

[UtahFlyGuy]

Could be clogged jets to me.

[Danny]

Have you pulled the spark plugs, poured a tiny tiny bit of fuel straight into the cylinders and then cranked it over?

Someitmes that gets a cold engine running again.

How about timing?

[westay]

I've pulled the plugs to make sure I was getting spark, but haven't done the fuel in the cylinder trick yet.

I'm not sure how to time a two stroke engine. While I took apart the carburetor, I didn't take the crank and magneto apart so I don't know what is under there.

[jonescort]

Check compression. Clean your valves and jets. If you need any help let me know, I have a parts washer and all the goods to work on any engine.

[westay]

Thanks Cort, valves and jets are clean. It was one of the first things I checked when I tore down the carburetor.

[westay]

Cort, compression if anything is too high. I've got good compression. I just ain't got no gas.

[jonescort]

Does it use a fuel pump?

[jonescort]

Is the gas tank located above or below?
Is it gravity fed?

[westay]

Cort, this is almost as old as I am. No, it does not use a fuel pump. No, it is not gravity feed. The tank sits in the bottom of the boat below the motor. As far as I can tell you push a little vacumn pump until the line fills with fuel. Then the compression of the engine pulls the fuel from the carburetor into the cylinder.

It's entirely possible I'm missing something though as I've never worked on an old two stroke before. All my mechanic work has been on 4 stroke auto engines.

[UtahFlyGuy]

There are a few manuals to these motors online but from what I've seen they want about 75 bones for them.

[Danny]

I've pulled the plugs to make sure I was getting spark, but haven't done the fuel in the cylinder trick yet.

I'm not sure how to time a two stroke engine. While I took apart the carburetor, I didn't take the crank and magneto apart so I don't know what is under there.

The engines I've messed with have a little pin that lines everything up (on the crank) for timing. Sometimes that pin can shear and throw everything off.

I would try the fuel straight into the cylinder trick. If it fires a few time and then stalls, some how your gas obviously isn't traveling from the tank to the cylinder. If it won't even fire then, well...who knows.

[jonescort]

Disconnect the fuel line from where it enters the engine. Hold it above the gas tank , set the line in a small bowl, and pump the little pump. If you get enough fuel in and it starts to feed itself you don't have a problem. I have an older briggs that wasn't getting gas where it needed to go. Did this test and thats how I figured out what was wrong.

[raynanwalt]

I think that the hoses or connectors on the hoses have a tiny leak and the gas flow is inadequate because of the air leaking into the flow where the gas should be.
Ray (Izaak) Walton

[westay]

Thanks to all. I'll try the suggestions and see what works.

[MickG]

insert hand into pocket pull wallet out get credit card out and buy a new motor.
The End

[westay]

My wife wants to reclaim her craft room where I have the motor spread out. She keeps asking how much it would cost to just buy a new one. It might happen but I hope not.

[cfonnes]

My old motor has a pump bulb (primer) on the gas line. I pump the heck out of it until I can no longer squeeze it, then the engine start fine.

Maybe you are not pumping enough.

[westay]

I've been researching and have found how the gas system works. In a two line system the fuel goes from the tank to the carburetor and air is forced from the motor down the air line into the pressurized tank.

Therefore, if gas is not flowing either there is a leak in fuel/air circuit or there is a blockage. It should be easy to determine which.