1955 5.5hp Johnson, a real puzzle

[lindy46]

Here's a good one - I'm about to cry "Uncle"! I have a 1955 Johnson 5.5hp and it just won't run. Compression is 65psi & 69PSI. I've replaced everything under the hood - coils, points condensers, plugs, and wires. I've rebuilt the carb, I've adjusted the synchronization. She will sputter, sometimes run for maybe 5 seconds, and then just dies. You have to pull and pull on the starter, and sooner or later she will fire again and die. Tried 2 different gas pressure gas tanks, thinking maybe a tank problem - no. Any ideas?

 

[jonesg]

Re: 1955 5.5hp Johnson, a real puzzle

Not enuf compression, it might be ring blowby, have you tried some seafoam to decarb it, the rings might be stuck.

 

[wbeaton]

Re: 1955 5.5hp Johnson, a real puzzle

65-69 psi is on the borderline, but don't blame compression, yet. Have you tried spraying pre-mix gas directly into the carb? Are the wires connected to the right plugs? Points and spark plugs gapped to .020" and .030" respectively? Are you getting good spark?

 

[Whoopbass]

Re: 1955 5.5hp Johnson, a real puzzle

I've had small outboards run fine with 55 psi and higher so I doubt compression is the issue unless older outboards need more compression to run.

 

[samo_ott]

Re: 1955 5.5hp Johnson, a real puzzle

I agree it's borderline also but should run... It must be something else... If you're getting a good strong spark and the wires are on correctly, then it's gotta be in the fuel system, so try as Wayne suggests and spray some pre mix right in it and see what happens...

 

[JB]

Re: 1955 5.5hp Johnson, a real puzzle

Go to Engine FAQs, Lindy. Do "Outboard won't start" as though you have done nothing to the engine. Something may not have worked. . .like the carb cleaning.

Let us know what you find.

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

65-69 psi is on the borderline, but don't blame compression, yet. Have you tried spraying pre-mix gas directly into the carb? Are the wires connected to the right plugs? Points and spark plugs gapped to .020" and .030" respectively? Are you getting good spark?

The plugs and points are gapped properly. Plug wires are correct. There is GOOD spark. I've also been spraying premix gas directly into carb. I've had the carb open several times and all is well with the carb. The needles look good - not worn or bent. Wonder if it could be the reeds in the intake manifold?

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

Soaked cylinders overnight in Seafoam - checked compression again and now up to 74psi and 78psi. 1/4" strong spark. Still won't fire with tank hooked up, and spraying premix in carb. Bummer

 

[JB]

Re: 1955 5.5hp Johnson, a real puzzle

Do the troubleshooting, Lindy. You are just easter-egging.

 

[Silvertip]

Re: 1955 5.5hp Johnson, a real puzzle

Spark, fuel, air and it all has to happen at the proper time and it will run. Miss any one or more of these factors and it won't. You either did something wrong or the engine has other mechanical issues. But this is a two stroke so unless there is an air leak or crankcase seal leak, it should run if all else is normal. If spraying fuel into the carbs doesn't make it run, I'd look at spark issues as well as timing.

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

Go to Engine FAQs, Lindy. Do "Outboard won't start" as though you have done nothing to the engine. Something may not have worked. . .like the carb cleaning.

Let us know what you find.

Went to faq's, typed in "outboard won't start" and it came back with no matches. Tried typing "starting problems" and got the same result.

 

[jbjennings]

Re: 1955 5.5hp Johnson, a real puzzle

lindy,
Most of the time when I've found I had to crank numerous times to start a motor and when it finally did start only ran a short time and died, then all over again, it was because it was flooding out. When you pump the primer, does it ever get firm( the needle valve stops letting fuel in)? If it does get firm, keep a small amount of pressure on it and see if it will bleed down (slowly put fuel in the carb because the needle is leaking).

Also, try taking out the plugs and cleaning them. Take the fuel line connector off the motor and pull until it cranks. Once it dies, put some fuel/oil mix in the carb throat. Does it start right up and run until it runs out of fuel? If so, it's your carb, fuel lines, or related stuff. If not, then some other problem. I think we all agree that even with 60 lbs. it would at least run. With 75lbs. you'll get it running nicely.

BTW, if it's your reeds being blocked or bent open, you'd never get it cranked without putting fuel directly into the cylinder. Reeds are almost never the problem, although I got some bugs in one one time that were blocking about 2 or 3 of the leaves open.

Are your spark plugs really wet after a few pulls? That could be a sign of flooding... At least your spark sounds good if it jumps 1/4 inch gap with a blue pop.
Keep describing the situation for us with as much details as you can, even the most insignificant tidbit.
If it makes you feel better, you're not going to believe how smooth it runs once you get it right. And easy starting----it will start almost looking at the starter grip!
DOn't give up! YOu'll get it.
JBJ​

 

[Vic.S]

Re: 1955 5.5hp Johnson, a real puzzle

Went to faq's, typed in "outboard won't start" and it came back with no matches

it is THIS POST on the Engine FAQs board.

Initiative test to find it but it is near the top so you failed

Some others in the FAQs that might be of interest too.

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

lindy,
Most of the time when I've found I had to crank numerous times to start a motor and when it finally did start only ran a short time and died, then all over again, it was because it was flooding out. When you pump the primer, does it ever get firm( the needle valve stops letting fuel in)? If it does get firm, keep a small amount of pressure on it and see if it will bleed down (slowly put fuel in the carb because the needle is leaking).


JBJ​

Interesting - I tried pumping the primer on the tank to get it real firm, but once it gets pretty hard, gas starts squirting out the hole, arrowed in the attached photo. Should it do this?

 

[Rick.]

Re: 1955 5.5hp Johnson, a real puzzle

I'm not familiar with your carb. but no it isn't normal for gas to squirt out. It would seem to me that your needle and seat aren't closing just right. You may want to take the carb. apart and check for foreign matter in the seat. Also check that your float floats (not water logged). Rick.

 

[jbjennings]

Re: 1955 5.5hp Johnson, a real puzzle

It only takes a TINY piece of debris between your needle and seat to cause it to leak and flood your carb. If you have a cork float, you will likely need to replace it with a plastic one. You can get it from your local BRP dealer. It comes separate from the carb kit, I believe. Or you can just order one from laingsoutboards.com If the float needle valve leaks, it will cause the problem you've described. Have you replaced the old fuel lines? A lot of time they will rot and put debris in the carb and cause your problem.
Good luck,
JBJ

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

Found a "new" old carb on ebay for $10, rebuilt it, installed it, and the motor started right up! Got her adjusted so she starts 1st pull and purrs like a kitten. Now the only problem is a gas leak at the intake manifold - so now I have to take everything back off and find/replace the gaskets. Always something with these old motors.

 

[jbjennings]

Re: 1955 5.5hp Johnson, a real puzzle

Glad you got it running, Lindy! Just be sure to be careful that you be certain that you get every single screw out of that intake manifold so that you don't try and force it and warp it. I believe there is a screw or two behind the carb in the center of that manifold that you don't want to miss, but I could be wrong because I don't have a 5.5hp.
Good luck,
JBJ

 

[lindy46]

Re: 1955 5.5hp Johnson, a real puzzle

Well, unfortunately, this motor is turning into a money pit! Turns out the reed plate is the problem - it has a good sized nick in it, underneath the gasket, so the gas is just running out the opening. So I guess I need to get a new reed plate (and gaskets). Any ideas where I can find one cheap? I've already got $150 tied up in this motor, not to mention the hours and hours of labor, and I had bought it as a re-sale. I may just keep it, or use it as a parts motor since I'll never get my money out of it.

 

[jbjennings]

Re: 1955 5.5hp Johnson, a real puzzle

Reed plates should be dirt cheap. Try placing an ad on aomci.org's free webvertize and I guarantee you someone will have one. Or try laingsoutboards.com, they will have one for sure but be more expensive than the aomci members. Ever thought about some JB weld on the reed plate, and sanding?
Good luck,
JBJ