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Just a couple pics of a rare 4 bolt Mc6 I just finished

Nice motor as always, Scott. Ron has some of the 4 bolt blocks. Wish I had a NOS 4 bolt Mc10! Ted

Scott,

All three of my Mc6s (two were complete when I got them) have coils with the wire that runs from the points to the coil hard soldered to the coil so you can only remove the coil if you disconnect the wire down at the junction where the condensor wire attaches.
I see that the motor in your pics has the more common arrangement with the wire that plugs in to the recepticle on the coil. Is that the way the more was when you took it apart or did you change to that setup for convenience?
I also noticed that the four bolt version is beefed up with more material visible on the exterior around the area where the cylinder liner ends... did they add material any where else?
Steve O'Hara

Steve,
I didn't see any changes on the back of the block but on the front in addition to the beefed up side wall there is an added gusset on the side mount boss below the fin and an additional gusset on the PTO side intake manifold mounting tab.

On the coils, this and one other Mc6 are the only ones that I have received complete and un-molested and both have the connector type coil assembly. The other was a 3 bolt block but had the later flywheel and flatback carb. I am familiar with the hard wired coil that you are talking about because many of the early saws used them including the Mc15 which was a 60's low cost saw.

Maybe Tom can chime in on this with his coil experience?
Scott

I remember having to deal with the soldered primary wire on a number of Mc10's and Mc6's. We always ran maverick ignition operated by a normally closed button switch, and had to either split the primary wire or unsolder it from the coil. TJ

My two unmolested Mac 10s both have the soldered primary wire.
Bob

Mc-10 coils have two hard soldered short leads with female bullet connectors on the free end. One is for a kill switch and the other is for the points. There is a plastic sleeve over the connectors to insulate them. No need to unsolder them, just disconnect them.

crap, now I have to take the flywheel cover off my Mc 10 to see how it is wired... been too long since I restored it to remember.
I've arrived at the conclusion that there is no such thing as a "correct" Mc 6.... seems there are at least a half dozen variations!
Steve O'Hara

PS... Tom.... that is the only coil I have ever seen with gap setting specs printed on the coil... always something new when we get these discussions going.

Tom,
I checked my Mc10s and they both have the female connectors as you describe.
Bob

Earliest style Mc-6 coil as far as I know. Right or wrong I converted my Mc-6s to the later non soldered style because I have all the NOS parts required to make the switch. Steve, yes .008" - .010" air gap.
You'll notice that the plug wire location on the Mc-10 coil is on the top while the later coils have it at the bottom. The later coils work on Mc-10s but getting the wire and grommet up and thru the notch on the head shroud is more difficult.