Rub marks on magnets mystery

[Dave Young]

I have an engine apart to replace the clutch plates and brake drum. Just noticed these rub marks on the magnets. They are 5.25” off center. I’ve looked extensively at the area of the mag ring and see nothing that has been causing this interference. The oil pipe is intact and is 4.5” off centerline. Baffled. Any ideas? Nothing is laying loose in the oil pan either.

[Dave Young]

More pics. By they way,

Dave Nolting’s new drums are spectacular!

[Jerry VanOoteghem]

Have you had this engine apart in the past and not see these marks then? If not, then I would say that in the past, an oil funnel came loose and did this. That you don't see signs of a messed-up funnel now, is probably because someone before you fixed it.

[Norman Kling]

I had one which had just been reassembled. Apparently the funnel for the oil line was just touching the magnets, because the first trip out The magneto quit working. So I drove it on battery for about 5 years. I was rewinding magneto coils and did 3 of them. So I decided to put one in the car which had quit running on magneto. I found the funnel laying in the crankcase and had been driving it for 5 years with only the line and no funnel and the magneto plug oil line. It got enough oil, but the magneto coils had been cut. So maybe your magnets have been rubbing on the funnel.
Norm

[Dave Young]

Well, seems like the funnel is the only thing in that area and it shows no evidence of contact since last rebuild, so I’m good to continue. Thanks

[John kuehn]

I bought a new oil funnel for my 1919 Runabout on the rebuild several years ago and noticed when I installed it the funnel was a little wider than the original. After running it for about a year I went to start the engine only to find it had a clunk sound. Pulled the engine and found that oil funnel had come apart and was hung between the ring gear and crankcase! That was a lesson to make sure the new reproduction wider funnel itself clears the flywheel magnets enough! Seems like I remember the original oil line was the earlier one and I replaced it with the later larger length wise earlier one. I think that the larger funnel is an improvement over the older one and thinking back it was a recommended change.

The repo funnel mouth was open more than it was supposed to be and eventually it started rubbing on the magnets. The next on I bought I closed up the funnel opening and it’s been working fine the last 15-20 years.