1955 Johnson 5.5

[jbjennings]

Re: 1955 Johnson 5.5

Compression on the cylinders is 60-65 psi.

There is fuel in the carburetor bowl, it spilled out when I removed the high speed needle to check it.

The spark on the inline tester wasn't a big blue zap, it was more like a medium orange zap. Could it be dirty points? I suppose I could clean them.

I think that's your problem. COmpression may be low due to stuck rings as well. I would get good spark and proceed from there. You may luck out and once you get it running, loosen up those rings with some seafoam in the mix.

 

[HighTrim]

Re: 1955 Johnson 5.5

I would go back to the ignition and revisit it. Very often carb issues, are not carb issues at all.

Dress the points lightly with either a points file, or a piece of wet/dry folded over an old hacksaw blade. Run that through the points, then dip a business card, or paper stock in acetone and run that through a few times to clean.

 

[derrTderr]

Re: 1955 Johnson 5.5

Ok, I'm going to clean the points this morning and see what happens.

 

[HighTrim]

Re: 1955 Johnson 5.5

Also make sure that the coil laminations are right on the edge of the mounting boss. Too far in and you will limit spark. Cannot remember, did you do the coils?

 

[derrTderr]

Re: 1955 Johnson 5.5

I will check to make sure the coils aren't too far in when I clean the points. They are new coils and I checked the resistance of the primary and secondary windings when I installed them.

 

[derrTderr]

Re: 1955 Johnson 5.5

Ok, I just cleaned the points and verified that the coils are flush with the mounting boss.

Unfortunately the situation remains the same. The motor sputtered a little and then no signs of life.

 

[HighTrim]

Re: 1955 Johnson 5.5

Ill go back to where Frank was headed with one of his earlier questions. I have had a couple of these 5.5hp motors with broken shock absorbers that would not start. You can often pinpoint this by stiffness turning the crank. It would take experienced feel though with good ones to tell the difference. The extra tension will actually not allow it to run.

Your compression is on the low side for that model. It is even though, so should start at least. That is depending on the accuracy of your gauge as well, some read different than others.

If it is sparking and jumping a 1/4" gap, and fuel is getting to the cylinders, it would have to be one of the above. Do you have another gauge? have you tried adding pre mixed fuel into the cylinders directly? Will this get it to fire momentarily?

 

[derrTderr]

Re: 1955 Johnson 5.5

I haven't sprayed premixed fuel directly into the cylinders through the spark plug ports. I will try that tomorrow. The compression gauge is one I bought from Autozone only a couple days ago and it's the only one I have.

I will rebuild the lower unit again and see if there is something fishy going on down there tomorrow too.

Thanks guys, my old lady and I took the boat out and paddled around today sans motor. It was still fun.

 

[HighTrim]

Re: 1955 Johnson 5.5

The shock absorber is beneath the water pump. It should measure 6 3/4" long, any more and she is broken. They can be welded, but Im not a fan of that. I would rather find a good used one.

 

[naturelover]

Re: 1955 Johnson 5.5

Ill go back to where Frank was headed with one of his earlier questions. I have had a couple of these 5.5hp motors with broken shock absorbers that would not start. You can often pinpoint this by stiffness turning the crank. It would take experienced feel though with good ones to tell the difference. The extra tension will actually not allow it to run.

Your compression is on the low side for that model. It is even though, so should start at least. That is depending on the accuracy of your gauge as well, some read different than others.

If it is sparking and jumping a 1/4" gap, and fuel is getting to the cylinders, it would have to be one of the above. Do you have another gauge? have you tried adding pre mixed fuel into the cylinders directly? Will this get it to fire momentarily?

What would be good compression numbers for these motors?

Could it possibly be out of time?

 

[HighTrim]

Re: 1955 Johnson 5.5

80 to 95 psi or so.

Timing is fixed, not adjustable. You can only adjust the points timing which he said he did.

 

[jbjennings]

Re: 1955 Johnson 5.5

If you've only got an orange spark at 1/4" gap on the tester, you still aren't getting enough spark to ignite the fuel --just my opinion. There's something wrong or it would be a hot blue pop.

 

[Crosbyman]

Re: 1955 Johnson 5.5

can the side bearing oiler hose be cracked causing a vacum loss in the crankcase ?

 

[derrTderr]

Re: 1955 Johnson 5.5

The side oiler hose looked fine on my inspection. I suppose I could replace it anyway just to eliminate that issue. What kind of line should I replace it with?

What should I be looking for in regard to the ignition system to get that hot blue spark?

 

[jbjennings]

Re: 1955 Johnson 5.5

Did you re-use old wires? Cut off about 1/2" to get to good non-corroded copper. New wires? Did you push them onto the coil p9ns, or screw them in (screw them onto the pin). Did you change the condensers? If not, I would since bad condensers will cause weak spark. Those ignitions can be finicky, but will give a nice hot blue spark when working correctly. I'll bet that if your spark is orange, that is the main reason it won't crank. Even with only 60psi, you'd get it to at least run, it just likely wouldn't idel well. Your gauge could easily be wrong as well--very common. Good luck...

 

[derrTderr]

Re: 1955 Johnson 5.5

I purchased all new ignition components when I first started working on this motor in late 2009. Everything has been sitting in my garage covered in a shop towel. None of the components look corroded or anything like that.

I purchased and installed new coils, condensers and points. I also installed new spark plugs and spark plug wires. I screwed the wires onto the coil spike with decent pressure. I also cleaned the points, checked the coil primary and secondary windings and adjusted the timing. I verified the wires aren't crossed and that the coil laminates are flush with the mounting boss and all wires are neatly tucked away from moving parts.

 

[Crosbyman]

Re: 1955 Johnson 5.5

oiler hose can be simple fuel line hose* that fits the nipples but dont bend it to sharply at the top and bottom curves

I used NAPA fuel line and tye wraps

mine looked good on my 7.5 but upon removing it I found it on the brink of falling apart

 

[geoffwga1]

Re: 1955 Johnson 5.5

I purchased all new ignition components when I first started working on this motor in late 2009. Everything has been sitting in my garage covered in a shop towel. None of the components look corroded or anything like that.

I purchased and installed new coils, condensers and points. I also installed new spark plugs and spark plug wires. I screwed the wires onto the coil spike with decent pressure. I also cleaned the points, checked the coil primary and secondary windings and adjusted the timing. I verified the wires aren't crossed and that the coil laminates are flush with the mounting boss and all wires are neatly tucked away from moving parts.

I note that you said in post #30 when you revived this thread that you had overhauled the carburetor.I am assuming that that was 4 years ago and if the motor has been standing for those 4 years chances are it will need doing again really thoroughly,carefully cleaning out all the tiny passageways in the slow running area especially,and paying particular attention to the slow running needle packing,it will probably have dried out and shrunk in that time .(and the fibre gasket in the float bowl if there is one,I can't remember
The same really applies to the ignition stuff you did.Not so much the coils but definitely the points and plugs.On the subject of plugs I have on two or three occasions fitted new Champion plugs only to discover that one of them was arcing across the insulator to ground and was losing or had a very degraded spark.I changed the plugs to the Autolite equivalent (#353)and the problem went away.I'm not saying this is your problem but given the factthat we have tried almost everything else nothing should be overlooked.
Good luck,I'm sure we'll get to the bottom of it eventually.
geoffwga1

 

[derrTderr]

Re: 1955 Johnson 5.5

I purchased new spark plugs from Autozone in the last month when I started working on this again. I rebuilt the carburetor again but was still using the repair kit parts from four years ago.

When you talk about the packing washers, I'm thinking that maybe I should replace those with some new ones. Also, is there a way to test condensers? Everything else in the ignition checked out good. I read a thread on here where someone expressed worry that the flywheel was damaged. How can I tell if there is something wrong with that?

 

[nwcove]

Re: 1955 Johnson 5.5

i doubt the packing washers are giving you any issue, are the needles loose? you need a special gizmo to properly test the condensors, they are rarely bad from new, and it would be a long shot to think that you got two bad ones! weak flywheel magnets are another longshot, but you can test them by dangling a screwdriver about a half inch away , the magnets should pull the screwdriver in with authority.
have you tried a few drops of premix directly into the plug holes as suggested? are you positive that the fuel pump is plumbed correctly?