Phelon coils Mercury

[mercuryman]

Has anyone been successful in replacing Phelon coils with the universal OMC coils in 2 cyl Mercuries like Mark 10.

[jasonh]

Yes, I have done conversion many times. Work ok for phelon up to mid 63 when they changed to later phelon. You have to file laminates a little to fit coil on. I hand file them to get the nice and even. You may have to use dremel or round file to make passage in webbing under coil for spark plug wire . Longer plug wires are need to reach around. There are instructions around. I could dig them up if you PM me an email for them.

[jeff-register]

Jason is 100% correct. Take your time, pay attention to detail & the swap will work well.
Jeff

[mercuryman]

JasonH I followed your instructions and got the OMC coil to fit tight on Phelon laminates, connected the spark wire and checked for a reading through the secondary winding and primary hooked up points and condenser. Got a very weak spark turning engine with a electric drill. The engine is a 1957 Mercury Mark 10. There is no is no way the adjust the clearance between laminates and magnet. The coil I am using looks new tomorrow try it on my lightwin. Where did I go wrong ?

[RICHARD A. WHITE]

Did you use the same condenser??? I am not positive that the OMC and Mercury condensers are the same value. If using an OMC coil, use the correct OMC condenser. That is how I did my Neptune Mastertwin sparks just fine….

http://www.richardsoutboardtools.com
classicomctools@gmail.com

[dave-bernard]

the lams you are using are the merc’s correct so that would not be an issue

[jim-moffatt]

I will add a couple cautions.

1. You should remove the minimum metal possible for the omc coil to fit the merc laminations. The merc laminations are matched to the magnet spacing on the flywheel which you cannot change. Narrowing the center laminations will change the relation to the flywheel magnets and MAY reduce spark. I have no idea whether the reduction is significant or not.

2. As Richard said,The omc coil is matched to the omc condensers so that should not be an issue. But the merc condensers should also work fine.

[jasonh]

I didn’t give instructions rather a description of general process. I offered to dig up the detailed instructions. You never asked.

Basic troubleshooting needs to apply here. I have never had issues.

When I do it, I file even amounts off each side of laminate leg.

Did you use new plug wires and good condensers? Did you wire to correct points? Phelon laminates need to be mounted were originally mounted. Can’t swap them around. They were mounted then machined for proper air gap at factory. Besides that, tough to troubleshoot over internet. I assume if you are willing to take on conversion you are comfortable with ignition systems. You need to go down line and troubleshoot. Sounds like you used unknown coils. Verifying coil seems logical.

[mercuryman]

Thanks for the reply for some reason the PM’s I sent didn’t go out. I have converted Scott Atwater motors but not Mercury. Some part is bad or not connected correctly . Thanks

[jeff-register]

Again, Jason is correct. The windings in each brand coil are matched to the capacitor. When buying the coils, try to get the matched electrically capacitors to be sure the assembly is correct. Coils matter by size of winding wire & how many wraps per lamination as well as fitted windings & laminations.
another issue I have seen is current reversing due to loose stator to block requiring a bonding conductor between the magneto & engine block. The bonding conductor stops any reversing of current into the other cylinder magneto with Phelon mags.

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