Oil in magneto?

[AHS]

47 Cub. Right down below the coil, there is a series of (magnets?) The magnets are covered with a film of oil, there is a oiling point right there. Should there be oil there? As I was taking it apart, I remembered the previous owner said “it’ll run for about 30 minutes then die on ya” it was the coil! All burnt and crispy! There was water in the transmission. There is fresh oil in there now, I probably should change it once I get it up and running.

[Rick Spivey]

If you can see oil in that area, then either someone over-oiled the magneto, or your governor seal is leaking. Does the oil look very clean, or is it somewhat dirty like engine oil? The governor seal can be replaced by removing the magneto, but there is a special insertion tool to help get the new seal inserted to exactly the correct depth. It can be done without the tool, but requires close attention to the depth when installing.

[inairam]

If the magneto was soaked and PO was using an external coil it may be time to get the mag rebuilt. The 47 would have had a mag and not an external coil. I have used this guy several times and have been very happy. http://www.rebuiltmags.com/

here is a post about the tool http://www.farmallcub.com/phpBB2/viewtopic.php?t=94808

[AHS]

If you can see oil in that area, then either someone over-oiled the magneto, or your governor seal is leaking. Does the oil look very clean, or is it somewhat dirty like engine oil? The governor seal can be replaced by removing the magneto, but there is a special insertion tool to help get the new seal inserted to exactly the correct depth. It can be done without the tool, but requires close attention to the depth when installing.

Ok, I oiled it. The oil looks clean. Should I wipe it off? What should be oiled by the oil cap? I have new gaskets for the magneto. All I need the puller and the wooden tool? I saw the magneto on the website, but I’m too far into it! And it’s expensive!

[SONNY]

Thats the problem with mags. EXPENSIVE!!!

[Glen]

Hi,
If you remove the magneto and oil runs out from the area where the magneto drive is, the magneto drive oil seal is probably leaking. It is engine oil leaking, unless someone has put lots too much oil in the magneto oil cup.
The oil cup oils the magneto bearing.
The area between the magneto and the magneto drive oil seal is supposed to be dry of oil.

The magneto drive is made on the end of the governor gear.
TM Tractor has a new oil seal for it, below is their listing.

http://www.tmtractor.com/new/gv/436fp.htm

If you replace it, check the seal surface on the governor gear, if it is rough, or has a groove worn in it where the oil seal was running, use fine sandpaper and smooth the surface. Clean off all sanding with a clean rag.

Be sure to install the new seal with the seal lip facing ahead.
Watch closely when installing it that the seal lip doesn't turn backwards, it won't seal if it turns backwards.
Put oil on the seal rubber, and the governor gear surface, before putting the new seal in.

Below are pics of the magneto drive oil seal, installed in the engine.
The 2nd pic has the governor removed.

[AHS]

Ok, let me look at the tractor again and see if it’s leaking.

[Rick Spivey]

You should only need to put a couple drops of oil in the magneto, maybe twice a year depending on usage; maybe only once a year.

[AHS]

Ok, grease at the bottom of the magneto drive, I mean what ‘looked like grease’. AND.. the gasket was split at the top of the magneto drive.. it looked like a homemade gasket. There was grease all around that area.. what is it to remove the magneto drive to replace the seal? There is nothing on YouTube about it.

[Bill V in Md]

To remove the old governor seal you will have to remove the magneto. I also prefer to remove the governor to drive the old seal out from the governor side. I have heard that it is possible to remove the magneto oil seal without removing the governor, but I think it is too difficult. Just remember (before removing the governor) to position the engine at top dead center on the compression stroke and that will allow you to reinstall the governor and insure you have the governor gears meshed properly with the idler timing gear so they are timed correctly with the ignition. The governor and idler timing gears are both marked (punched) to insure they are timed properly after installation, and this is much easier to do before you install the new oil seal. After the governor is installed, you can install the new magneto oil seal.

Also be sure to install the new seal at the correct location or depth. There was a special tool made and sold by one of the forum members (Earl Fauble) years ago, but not sure he is still selling them. There are also several posts by members including Raymond Durban that made their own tool out of wood. It makes driving the seal to the proper depth much easier.

Good Luck,
Bill

[Glen]

Hi,
Below is a post I put info on about replacing the magneto drive oil seal.
It has pics of the governor gear, the idler gear, and shows the timing marks.
My post is the last one on the page.

viewtopic.php?f=1&t=110067

[AHS]

You guys are so awesome! The #1cylinder is at TDC. First of all is to remove the governor. Is there any other seals/gaskets I should be worried about, that I have to replace?

[Bill V in Md]

I believe the only other gaskets you will need to replace are the governor housing and magneto housing gaskets.

[Dale Finch]

If it wasn't mentioned, while you have both the mag & gov off, and have removed the old seal, look for the tiny dot (punch mark) on the mag side of the gear, looking in from the mag side. Then make a corresponding mark on the gov side (chalk, punch...) so that you know how to align the gov once the seal is in place.

[Glen]

Hi,
Below is a page from the Cub service manual showing the parts of the governor, and linkages.
To remove the governor, you need to remove the shaft number 30 in the pic, by pulling it out of number 8 in the pic.
Remove pin number 3, then the 2 bolts holding number 5 onto the engine, and the shaft comes out as an assembly.
Check key number 6 for wear, it is common that they wear.

When it is assembled, check number 30 for looseness in number 8, by turning it forward and back.
If it is loose, it can make the governor work slow.
People tighten it by replacing the key, a hardware store or auto parts store may have them.
The key is sometimes tight in the keyway in the shaft.
Then if 30 is still loose in 8, people cut 1 or more small strips of an aluminum can and fit in the connection. It has to have the right thickness of material to fit in the space, it might need something other than an aluminum can.

http://www.farmallcub.info/manuals/gss- ... 002-15.jpg

Below are listings for the gaskets mentioned above, from TM Tractor.

http://www.tmtractor.com/new/gv/289fp.htm

http://www.tmtractor.com/new/el/725fp.htm

The long throttle rod from the throttle lever has to be disconnected at the governor also to remove the governor.
Check that the long rod fits well in the clip near the right rear of the head, the clip keeps the rod from flexing up and down.
The clip has it's own bolt to hold it on the head, with a 1/2" head, it doesn't use a head bolt to hold it on.
The clip should be straight and when the rod is in it, bend it mostly closed so it holds the rod. Be sure the rod moves freely forward and rearward in the clip.
Below is a pic of the clip from TM Tractor.