Magneto on 3T D7

The d7-3t can use too a AMERICAN BOSCH and a WICO magneto

If it is an odd fire engine, it can be so badly out of time that one of the times the mag fires, it isn't going to be anywhere close to TDC. Take your cap off and check when the impulse fires, the first time it should be on cyl #1[attachment=55984]15735234667813305562680282918998.jpg[/attachment][attachment=55983]15735233959416744845467749226811.jpg[/attachment]

The first pic, see where the rotor should be just before #1 fires, pointed at the #1 tower.
The second pic see where the cam is on the rubbing block? Cam turns counter clockwise and the next fire is only 90 deg for #2. This mag is the Eisemann RC-2Q.

Just to ad my bit .
I have several of these machines and feel i know the timing set up pretty well. Some good information on previous posts .
First job is to locate the timing marks on the flywheel. Remove the side plate on the flywheel housing and using a paint pen or similar highlight the timing marks on the flywheel for easier reference. Turn the engine over slowly with plugs removed as you have done . With a finger over no 1 plug hole turn engine over until compression starts to build , continue turning engine as slow as possible until impulse clicks. Spark should be seen at no 1 plug and flywheel marks should be at or soon after the no 1 tdc mark . Turn engine slowly another 180 degrees and no 2 plug should fire and no 2 will be at tdc . The crank will turn another turn and a half before this is repeated but the impulse will click every half turn of the crank. ie; no 1 will spark again at 3rd click . Spark advance is taken care of when the engine starts, by the impulse . When using this method, time engine to TDC mark not the MAG mark.
On a 3T there is really only 2 ways the mag can be fitted . Right and wrong. Assuming the correct mag is fitted .
Hope this helps.

Also, when looking for timing marks keep in mind that the flywheel turns opposite of the hand crank, at least it does if the crank was to come out of the front if the tractor. Crank out top of the hood? IDK!

Thanks to all of you for your valuable input.
It may be a few days before I can get back to the 3T, but I should be better qualified when I do.
Having the odd fire design explained should be a big help. The cap is configured as the one shown in Stephen's photo.
I have one idea about why my observation puts number two spark at such a strange time, but I won't go out on that limb
before I go back and make more observations.
When I know more, I will let you know.
For what it's worth, the tractor SN is 3T-8671

Another question on the D7.
The diesel fuel is "old enough to know better", but possibly not old enough to vote.
I have started quite a few old diesels without worrying about the fuel. They always seem to start and run.
I was just wondering if there is anything I should do, besides maybe changing the fuel filters.
Cat seems to be pretty proud of those rolls of string!
I don't want you to tell me to drain all the fuel, open the injector lines, purge them with new fuel, etc,. before attempting to start,
but i am inclined to defer to the wisdom of greater experience. The tractor's years of down time have been spent under cover, behind
closed doors.

I have started lots of engines that have been sitting for many years and have never had a problem with old diesel.
In fact I would suggest the older the better, as the old fuel, I believe, had better lubrication quality's than todays fuel. Just my observations though.

I would guess 15 to 30 year old fuel is better than 3 to 10 year old due to changes made.