Whats this hole?

[Patricktjms]

Smaller 1/2 hole just rear ward of the oil fill cap. On the housing between there and the mag. It isn't threaded. What's it for and should it be plugged?

 

[Jim.ME]

Smaller 1/2 hole just rear ward of the oil fill cap. On the housing between there and the mag. It isn't threaded. What's it for and should it be plugged?

Just a hole in the part of the housing that covers the shaft and coupling for the distributor or magneto. Reach underneath the housing and there should be a larger hole.

Based on the picture, you have a distributor not a magneto.

 

[Patricktjms]

Just a hole in the part of the housing that covers the shaft and coupling for the distributor or magneto. Reach underneath the housing and there should be a larger hole.

Based on the picture, you have a distributor not a magneto.

That's not my picture. That's just the only picture I could find on Google with the same hole. Mine is a 1950 with a mag.

 

[wore out]

That's not my picture. That's just the only picture I could find on Google with the same hole. Mine is a 1950 with a mag.

I've seen many with a good old fashioned cork in that hole.

 

[Brian G. NY]

I've seen many with a good old fashioned cork in that hole.

Exactly....my WD which was my Dad's has a cork stuck in that hole. I don't think the cork was factory; just seemed like a good place for a cork. LOL

 

[Nordic]

Smaller 1/2 hole just rear ward of the oil fill cap. On the housing between there and the mag. It isn't threaded. What's it for and should it be plugged?

If you have a timing light you can check your timing using this access hole. The timing is supposed to be set at 30 degrees advanced at full throttle. When your timing is correct you will see the head of the pin that is used to hold the mag coupler in place, while pointing your timing light at the hole. What really helps is putting a blob of white paint on the head of the pin. Best results are had in the dark or at least a shady place as the brightness of daylight makes it hard to see.

 

[Brian G. NY]

If you have a timing light you can check your timing using this access hole. The timing is supposed to be set at 30 degrees advanced at full throttle. When your timing is correct you will see the head of the pin that is used to hold the mag coupler in place, while pointing your timing light at the hole. What really helps is putting a blob of white paint on the head of the pin. Best results are had in the dark or at least a shady place as the brightness of daylight makes it hard to see.

That shaft turns at the same rate as the crankshaft?

 

[Jim.ME]

If you have a timing light you can check your timing using this access hole. The timing is supposed to be set at 30 degrees advanced at full throttle. When your timing is correct you will see the head of the pin that is used to hold the mag coupler in place, while pointing your timing light at the hole. What really helps is putting a blob of white paint on the head of the pin. Best results are had in the dark or at least a shady place as the brightness of daylight makes it hard to see.

The shaft in that hole drives the distributor and only turns half crank speed. Info I have is that the timing marks are on the outside rim of the flywheel, and you access them by removing the cover on the bottom of the flywheel housing which reveals an arrow cast into the flywheel housing (front center of the opening). That arrow is used to align the timing marks on the flywheel to.

 

[Tramway Guy]

The shaft in that hole drives the distributor and only turns half crank speed. Info I have is that the timing marks are on the outside rim of the flywheel, and you access them by removing the cover on the bottom of the flywheel housing which reveals an arrow cast into the flywheel housing (front center of the opening). That arrow is used to align the timing marks on the flywheel to.

The shaft in the hole turns just as fast as the crankshaft. The magneto(or distributor) has a gear inside to drive the rotor at half speed.

 

[wore out]

The shaft in that hole drives the distributor and only turns half crank speed. Info I have is that the timing marks are on the outside rim of the flywheel, and you access them by removing the cover on the bottom of the flywheel housing which reveals an arrow cast into the flywheel housing (front center of the opening). That arrow is used to align the timing marks on the flywheel to.

The mag drive turns crankshaft speed.

If a mag is used there's 2-1 gearing that drives the rotor, if a distributor there's 2-1 gearing in the distributor drive unit.

 

[Jim.ME]

The shaft in the hole turns just as fast as the crankshaft. The magneto(or distributor) has a gear inside to drive the rotor at half speed.

The mag drive turns crankshaft speed.

If a mag is used there's 2-1 gearing that drives the rotor, if a distributor there's 2-1 gearing in the distributor drive unit.

Ok, my mistake on the speed of that shaft driving the distributor/mag, thanks for the correction.

What about the timing marks? Did I miss on the location of those marks?

 

[Nordic]

Ok, my mistake on the speed of that shaft driving the distributor/mag, thanks for the correction.

What about the timing marks? Did I miss on the location of those marks?

You are right Jim, the timing marks are on the flywheel accessed under the tractor. It's not very convenient however, unless you have a second person helping with adjusting the timing while keeping track of the marks underneath using the timing light.