Your 4S6471 is a Wico # XH-2836S. This is the early model that uses the #88-5103 rotor but I still could not find any info on timing the gears. Perhaps a call to one of the magneto rebuilders would get an answer.

Thanks for all the input. I know I can do trial and error to make it work. Just wanting documentation to add to my library. I really like seeing it written down in black and white. If I find anything I'll make sure to post it here.

"Arthropod" wrote:

Green Horn, thanks for the pics. That isn't the same magneto as mine though. I've seen the type you have. Your rotor doesn't have a gear on the rotor, correct? The magneto in my question has a rotor with a gear on it and the rotor meshes with another small drive gear. The small drive gear has two teeth with a taper, which I assume is a timing mark. My question is when you slip the rotor in place, does the contact on the rotor point towards those timing teeth on the drive gear. I figure it does, but was looking for documentation on it.

I finally remembered to write down the Caterpillar part number.
p/n- 4S6471. I'll take some pictures of this mystery mag.

Hi just wondering if this was ever resolved. I have the same mag and my Cat book docent show this mag

I'm not knowledgeable about mags and want to time this correctly

Any help appreciate. Hope I'm posting right

Cat D2. 5U7061. Don't know the year, man told me it's a 52 model

Well this is several years late, but figure I'll update the thread.

Yes, the tapered teeth on the small gear were the timing marks. And the rotor has a small indent (mine has a white mark) that is the timing mark on the rotor. I placed the rotor in place so the indent that is in the rim of the rotor was pointing to the tapered teeth. When you spin the pony you will note that when the piston is at TDC the rotor is correctly pointing towards the plug wire in the cap.

By tapered teeth, is there more than one or do you mean tapered tooth as in one.

There are two teeth on the small metal gear that if you laid the gear flat on the table, two of the teeth taper downwards towards the outside of the gear. The taper is real obvious when you look at the gear. The small gear drives the rotor, which is of that ceramic material and has a set of gear teeth as part of its underside that mate with the small gear. I noted yesterday that the ceramic rotor has what I think is a timing mark notch on the rim of the rotor. As I remember I lined that notch up, centered on the two tapered teeth of the small gear the last time I worked on the machine (I think about five or so years ago I had mag issues that left me down in the woods). My rotor has a small crack developing in the ceramic material, but it has been like that for the past five years or longer. I think I'll smear some JB Weld on it this go round.

The reason I found my old post here was I was googling something else and this post popped up. I went to start my 1949 D2 yesterday evening and the mag is not firing. I have it apart right now for repair and was searching around for various parts. Bench testing it has no spark. I haven't dug in very deep yet, but hoping maybe the condenser is shorted. If not that I fear the coil has gone. Though I see they are available, so not the end of the world. This machine has been sitting for probably a year not started. Was running fine last time I used it, but my 1955 D2 has become my go to machine since it has a blade and mostly I am grading the road to the meadow when I crank up a D2. I was going to drag some logs yesterday and thought it would be fun to use my 1949, but instead I had the hood off the 49 and was into the magneto. Another kind of fun, but wasn't part of the plan.

Ok, thanks.
Lining up the rotor mark to between two tapered gear teeth makes sense.

I will transfer knowledge. Pictures attached of the Wico X magneto parts. Small gear with tapered timing teeth. Rotor with gear. Pic of the magneto timed.
you turn the magneto so the two tapered teeth face the rotor, then insert the rotor so that its timing mark points to the small gear teeth.

On the big drive gear that seats into the pony there is a V mark. On the gear inside the pony, from front side of pony you remove that plug so yo can see the gear face. Turn the pony by hand until you see a V or it might be an M, hard to see with my older eyes. Anyway, DO NOT USE THE 'O' mark. I have included a pic of the 'O' mark on the pony gear. I couldn't get a good pic of the 'V'. That 'O' is an internal timing mark for the pony. 180 degrees from the 'O' is that 'V' that is the magneto timing mark. When you can see the 'V' you then insert the magneto so its 'V' on its drive gear meshes with the pony gear. You sort of need to hold the rotor in position (it is pointing at #1 plug wire) and slip the mag into position. Little tricky.

Note that when I timed the magneto (little gear points at timing mark on rotor), I think the 'V' on the drive gear sort of looks out of position. Ignore that. Get the rotor pointing at the small gear. When you insert the drive gear correctly you will note the rotor is in the correct position for #1 of the cap.

I have included pics of the carb. In getting my machine running after sitting for I guess more than a year idle, I had to also work on the carb. The typical, stuck needle valve and that jet in the bottom of the bowl clogged. If your pony doesn't want to run unless you choke the snot out of it, that is usually a sign that little jet in the bottom of the bowl has crud in it.
I was lucky and in my spare parts I had an old needled valve that was all metal, not with that piece of crap rubber tip that all modern needle valves have.
So, machine is back working again. Hope this info helps others.

That's some good info, thanks for posting.
Doesn't seem to be much printed info out there on Wico/Cat installations.

Hope it helps others.
Ended up the condenser in the mag was bad. I had one of similar design that fit. Bench test drew fire.