Home › Forum › Ask A Member › Johnson HD-15 Magneto issues › Re: Johnson HD-15 Magneto issues
The compression won’t come up much until the rings have seated in the cylinders. A Zephyr I have took at least an hour of steady running before I noticed any rise in compression. Breaking in new rings can take a while. In the old days, they spun the motors somehow in the factory to break them in a bit and I’ve tried it using the lathe and spraying the intake occasionally with fogging oil to keep everything inside happy.
If you are getting frustrated, it’s best to put the motor aside for a while and work on something else. When you come back to this motor refreshed, it will be like a new project and you’ll have it figured out in no time. That works for me everytime!