1957 Johnson 3 hp - No Fuel In Cylinders

[hippovet]

I have tuned up a 1957 Johnson 3 hp - new ignition parts, rebuilt carburetor, new head gasket, etc.

It is generating a strong spark but won’t start. There doesn’t appear to be any fuel making it into the cylinders, even when I squirt some into the carburetor. I even tried starting fluid. Nothing! The plugs and cylinders are dry.

I checked, cleaned and reinstalled the reeds. Compression (cold) in both cylinders is 75.

What could be preventing fuel fuel from making it into the cylinders? What am I missing here?

i have tuned up several similar 3 hp motors in the past without having this issue.

Thanks

 

[Zack19919853]

Try spraying fuel in the cylinders to see if it will even bust off

 

[Zack19919853]

Should check compression when it’s warm as lubricants tend to thin as the get warmer

 

[hippovet]

I can’t warm it up because it won’t fire, at all.

I’ll try removing the plugs, spraying some fuel in the cylinders, replacing the plugs and then try to start it. Is that what you’re suggesting?

 

[hippovet]

I sprayed fuel into both cylinders, replaced the plugs, and tried to start it. Nothing. I sprayed starter fluid into one cylinder and tried to start it. Nothing. I rechecked the spark with my in-line plug tester and there appears to be a good spark. I tried different plugs. Nothing.

My next step is to try a different carburetor, although I don’t see why that should make a difference.

 

[oldboat1]

3/8 inch open air. Set it for a half inch and work back if you need to in order to find spark. You may not be getting fuel from the tank (valve open?), or the fuel is contaminated (water?), but should have popped when you used starting fluid.

 

[Rick.]

Sounds like the cab needle is stuck closed. Would be interested to know if you have fuel in the bowl? Rick.

 

[hippovet]

The fuel is a little old. I’ll replace it with fresh fuel. But, why didn’t it pop when I sprayed starting fluid into the carburetor?

There is fuel in the bowl. It might not be getting further than that. I’ve cleaned the carb twice.

I’ll do more work on testing spark. My in-line spark tester is a light.

 

[racerone]

Are the plug leads on the correct cylinder ?

 

[hippovet]

Racer one,

Good call. Oops on my part. However, after reversing the leads, it still wouldn’t fire. It got dark on me so I’ll see what I can do in the morning. I’m going to change fuel, reset the points, and try again. I have another carb I might try also.

 

[Zack19919853]

Plugs fouled? It should have at least tried to fire when squeezing gas into the cylinders.. maybe not getting good spark. I bought this one. I don’t think the light that you have works as efficiently as these and as the one noted above. You can actually see what spark your getting and adjust it. Also can hear a good snap. I would check with that and use fresh fuel and try again squeezing a little in each cylinder if that don’t work then seems as if you aren’t getting spark.

 

[Zack19919853]

I wouldn’t reverse the plug wires unless you are certain you have them backwards. I would make sure the are on the right cylinder as this could keep it from firing up!

 

[hippovet]

Excuse my ignorance but I’d like to know how fuel gets from the carburetor to the cylinders. I assume that fuel/air is drawn in thru the reed valves by a vacuum created by the pistons. I’m asking because it really seems like nothing is making it into the cylinders.

I ordered the plug plug tester in the photo. I think the plug wires were reversed because I compared them to the wires on the other three ‘52-‘67 Evinrude/Johnson 3 hp motors I have. I like these little motors.

I haven’t done anything today because I’m trapped inside by wildfire smoke. Fires plus COVID suck.

 

[racerone]

I would say you think you have strong spark.----I say you do not have strong spark !!

 

[hippovet]

I just stripped everything off of the stator plate. I’m starting over on the ignition.

 

[hippovet]

That worked. I cleaned the stator plate, reinstalled the points and carefully set them using an ohmmeter, and reinstalled everything else. New gasoline also. Started right up and ran great. I think the point gaps were too wide.

 

[racerone]

Using a meter and timing marks to set the points get you the strongest spark every time.

 

[Zack19919853]

Using a meter and timing marks to set the points get you the strongest spark every time.

I’m assuming a multimeter and a timing light racerone? Curious to know myself lol

 

[racerone]

Just need an ohmmeter to set the points.----Yes you can use a timing light and the marks on the flywheel and magplate.----You could check before and after the work.