Re: Johnson PO38

Home Forum Ask A Member Johnson PO38 Re: Johnson PO38


cajuncook1


Replies: 842
Topics: 72
#81214
quote Mr Harris:

Thank you very much. I have had the flywheel off while heating it up for that very reason. A manual impact is about the only thing I haven’t tried. I have one, but the biggest bit I have is a 3/8” and these screws are 3/4 across. Think that would tear it up? I already put a 3/8” slotted bit in my pneumatic impact and it just broke the bit right off.
I already have that parts manual and I did use the old school cotton plug wires. This ain’t my first rodeo, haha. When working on such an old machine a manual is usually my first move.

I will try to find or make a 3/4” slotted bit for my impact. If not, are the screws available?

Well, you having some experience working with these old motors, does help…..lol

Screws can be obtained from parts motors or someone in the club may have an inventory of some to sell to you.

I have not worked on Johnson PO motor, but do I have these models

1937 Johnson model 110 1.7hp
1937 Johnson model KA-37 9.2hp
1940 Johnson model HA-10 5hp
1948 Johnson model KD-15 9.7hp

The usual resistance is between 3 to 7 ohms, but on your coil and ignition I am uncertain. One of the other guys may offer guidance.

Another thing to consider, is your magnet. Pre WWII magnets were soft magnets that would require re-magnetizing. Post WWII are permanent magnets and require no maintenance. My Johnson KA-37 barely put out spark, but one of AOMCI members re-magnetized the flywheel magnets and I was getting big fat blue sparks jumping about 3/8 inch with a open air gap spark checker.

There are used condensers that are still good and can be obtained from members, but in the past several years the use of modern solid state condensers have served well with some of these old motors. I put one on the Johnson KA-37 and I have good spark. I am looking for the type and range of that condenser. If I can find it I will post it. Maybe someone who has the information on hand can post it.

Please post pictures or vids of your motor project. We always love a good project and pictures. Oh, I have sent the information to your email address under http://www.wetransfer.com.

Cheers,

Cajun