Hello, I am in the process of acquiring my second D7 Cat.  I looked at this one 12 years ago and the owner at the time decided not to sell it so I found a 1958 and have been running that for a decade now. Anyway, this one has a 3S2986 magneto on it and I am not able to find a breakdown of the parts so I can rebuild it. It has a tone of moisture damage under the cap and I need to replace points, condenser and coil. Hopefully that will do it. Tag is missing off the magneto but it is the six screw cover and the housing looks identical to the 3S2986. Not sure about the year of the machine but I am assuming its a 60 or 61. Cool think is that this has the early tilt blade cylinder on it the runs off a battery operated pump. Supposedly the first one delivered to NYS with that on it.

Any help in locating parts is appreciated

Gets worse, Cat also had a 3S2987 number on their magnetos, anyone know the difference between the 3S2986 and the 3S2987?

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I have some 3s2987 magneto but no 3s2986 these number fit on same machine

Looks like you have a tag that has been painted over on the mag. Remove the paint carefully as numbers may be painted on not stamped.      

3S2967 is a Wico XH2823S
3S2986 is a Wico XH2799
There are differences...
 

The 3s2987 and 3s2986 are liste for D7E and D8H and more but they fitt on 17A too and have too 7m4700 and 8m9145 liste for 17A WITH CAP 6 BOLTS.

Thanks for the information. I am starting to think that it is a 3s2987 and will get back out to try to remove the paint, not looking for a whole magneto but rather a points and condenser kit. Maybe a coil too.. As far as it being a D7E, it is my understanding that the !7A prior to 1961 and not earlier than 1959 was a D7D and the 17A D7E designation started in 1961 with upgraded HP and wet clutches. I can seem to find when the serial number start was for the D7E?

Looks like I need a WICO 1-5090 set of points, a WICO 2-5007 Condenser and a 5-5011 coil  according to magnetoparts.com and they have none in stock. These are the same for the XH-2799 and the XH-2823 magnetos. I also need gasket #12726. Any suggestions on where to purchase?

To my knowledge it is either a 17A or a D7E, it can't be both. Have you tried Brillman Company for magneto parts? They have a good online store interface that's easy to use.

I get my parts from "Mark's Magneto Service"
860-537-0376
Located in Connecticut