1958 Johnson 35hp running on one cylinder

Im restoring a wooden run about. check out my restore thread 1960 luger matador. And I have a 1958 Johnson 35hp on the back. She starts good every time has good compression. But it's only consistently running on the top cylinder. Everyonce in a while both cylinders will fire and she goes like mad. I changed the plugs and that seemed to help a bit. But it still loses the bottom cylinder. What's the first step in some of your minds to fix this problem? All the help would be greatly appreciated!! Thank you

Re: 1958 Johnson 35hp running on one cylinder

have you cleaned and gapped your points to .020 visually check the coil for any cracks,spark plug lead in good order.you may have to go through carby.I am just learning myself and my 1960 big twin 40 started only running on top cylinder turned out I hadnt tucked the coil wire in under the coil and the drive shaft rubbed against it causing it to short out cheers.

Re: 1958 Johnson 35hp running on one cylinder

Firstly, when cold do you have spark on both cylinders? Second, once warm do you lose the the spark in the bottom cylinder?

Finding spark issues is one of the most difficult problems to diagnose especially when the problem is intermittent. Once you have determined when the spark disappears the problem may be easy to diagnose.

If the problem exists when it is cold, try swapping the coils to see if the spark issue moves to the top cylinder. If the spark is now inconsistent on the top cylinder the problem more than likely is the coil. If the problem doesn't move then it may become more difficult but you have now at least narrowed it down to parts and pieces within the bottom cylinder ignition system (i.e. condenser, points, wiring).

If the problem doesn't appear to be the coil, do as nahoo7 has suggested. Inspect the points gap, wiring, and cam on the plate assembly to ensure it is withing specs. Check that the plate assembly is not loose (if this is the case it may shift enough that the breaker points will not have a proper gap). IF everything is within specs and the wiring is intact and not grounding I would consider swapping condensers. Normally if the problem only exists on a warm motor it is generally the condenser. Try swapping condensers to see if the spark problem moves to the top cylinder. If it does move to the top cylinder a new condenser is in your future (IMO I would replace both). If the problem still exists in the bottom cylinder it must be a wiring issue or the points may be bad. At this point try swapping points to see if the problem moves. If it does you have found your problem (or properly gapped the breaker points, this is very important that it has the proper gap before troubleshooting) and new breaker points are in order. If the problem does not move it more than likely is a wiring problem, double check and replace all terminals and splices.

I hope this helps you along the way. If you still have problems let us know.

Re: 1958 Johnson 35hp running on one cylinder

Awesome reply!! Thank you so much for taking the time for that response!!! I removed the fly wheel today and visually inspected the points, one point is very clean and looks good the second point is completely full of carbon. I replaced the plug wires and another set of new plugs as the other new set had gotten pretty fouled. I will be cleaning the points and seeing if that helps for my first step. Then will be trouble shorting as you outlined. The problem stays pretty consistent whether a cold start or when it's warm. Maybe a smidge better when warm but Not much. I'm not sure where my coil is??? Any advice where it is on this pic???

Re: 1958 Johnson 35hp running on one cylinder

Your coils (2 ea, 1 for the top and 1 for the bottom cylinders) are the two green things with the copper plates. Your condensers are the two silver things with the wire coming out of the top.

Re: 1958 Johnson 35hp running on one cylinder

HI FJ. These links and pics can walk you through an entire ignition rebuild. If one set of points has carbon deposits that makes me think you have a short somewhere beneath the flywheel. The coils themselves (the 2 big green things) are relatively new and are probably fine so I would focus on looking for a wire with worn insulation causing it to arc. You may have to disassemble the magneto, but it's easy to put back together. You can take pics with your pics along the way to hep too. Holler if you get stuck.

3 HP Evinrude Lightwin Ignition System Tune-Up 1952-1967

Re: 1958 Johnson 35hp running on one cylinder

looks like whoever replaced the ignition parts knew what they were doing! all wire tucked away nicely. if you dont find any chaffed wires, you may want to do some research on the cut out switch. im not sure if it can cause an intermittant issue but its worth asking about! ( its a safety feature to kill spark to one cyl if the motor over revs )

Re: 1958 Johnson 35hp running on one cylinder

Thanks a ton for the info!! Kfa that's an awesome description of how to work on this ignition system!! Thank you!! I'm going to begin as you say, clean the points and look for a loose damaged wire. Then go from there, I already found the rebuild kit for about 20 bucks so thats a definite possibility. I will work on it tomorrow and give you guys an update. Thanks a million for all the help everyone!!

Re: 1958 Johnson 35hp running on one cylinder

So I cleaned the points with all the carbon on it. And while inspecting the point with the carbon buildup I noticed that it looked like it wasn't hitting aligned. I'm wondering if that gap is creating an open spark allowing the carbon buildup. But I also can't seem to get them aligned to fit flush. Is the way that the two points are hitting against each other a problem??

Re: 1958 Johnson 35hp running on one cylinder

Does anyone else see a problem with that screw. It appears that it is not the right size and not securing it right.

Re: 1958 Johnson 35hp running on one cylinder

Another problem solved and another man save hundreds of dollars by the iboats heroes!!!!!!!!

So I took look at my points, And noticed that they weren't coming together flush. So instead of messing with old parts I decided to buy all new. I went to Napa And bought the tuneup Kit. I replaced the points and condensers Set the gap. And checked for spark I had spark on both cylinders. I put everything back together and fired it up, She's now running consistently on both cylinders!! Thank you so much for all of your help, The kind of person that's willing to help a unanimous guy on the Internet out is truly a good person!

It sounds like I might need a little bit of carburetor adjustment, But at least we're running on both cylinders to start from. Once again thanks a million!!!

Re: 1958 Johnson 35hp running on one cylinder

That screw is the adjustment screw, it kinda rides in that slot. The actual screw that holds the points in place is closer to the crank shaft and can't be seen in that picture.

Re: 1958 Johnson 35hp running on one cylinder

FJ_Russo said:

Another problem solved and another man save hundreds of dollars by the iboats heroes!!!!!!!!

So I took look at my points, And noticed that they weren't coming together flush. So instead of messing with old parts I decided to buy all new. I went to Napa And bought the tuneup Kit. I replaced the points and condensers Set the gap. And checked for spark I had spark on both cylinders. I put everything back together and fired it up, She's now running consistently on both cylinders!! Thank you so much for all of your help, The kind of person that's willing to help a unanimous guy on the Internet out is truly a good person!

It sounds like I might need a little bit of carburetor adjustment, But at least we're running on both cylinders to start from. Once again thanks a million!!!

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Glad you got her running FJ! Here's a handy link to help you get the carb dialed in.

http://forums.iboats.com/engine-fre...sorted-carb-variations-joe-reeves-167352.html