Magneto question

Whats the difference between an American Bosch MJK 4/2 360 B-410 and a MJK 4/2 360 C-410. The 360-B was on a D6 9U parts machine I bought several years ago, it has an impulse problem I'm tring to fix. The D6 I'm working on now has a WICO mag on it with a Cat part # 4S6470. My parts book doesn't show a WICO mag in it. Did the D6 9U's come with WICO mags at some point?
Thanks.

Rick, maybe this will help some.. Dont know about the Wico though..

Magneto Numbers-----------------------
Here is a listing of MJK starting engine magnetos that should help keep someone from buying the wrong magneto. You will need a parts book for the machine you are wanting to buy a magneto for and procede from there. On any areas I have listed that says "should be", I did not have a listing for that particular vintage of MJK magneto listed in my American Bosch book and had to go to a latter vintage of magneto with the same numbers. Example: MJK 4A 409 Caterpillar part # 3F8575, I did show an A vintage of magneto, but I showed a MJK 4C 409 magneto that usually means it supercedes the previous letter vintage. I can not state that I have made no errors, this took some time (too much time).

Craig

The number in the top row is the Caterpillar part number.

'=degrees

The right hand most number listed in the second row tells the rotation of the magneto when looking directly at the impulse hub or drive gear. American Bosch had a direction of rotation indentifier built into their application numbering system. Even numbers are clockwise (cw) and odd numbers are counter clockwise (ccw).

flange mounting = mounting flange bolts are vertical

horizontal flange mounting = mounting flange bolts are horizontal

I did not research which flange mounted magnetos stand on end. Any that do have to have spring loaded impulse weights so they will latch up due to the fact they can not fall into place by gravity.

1H3572
MJK 4/2 360' C417
ccw / horizontal flange mounting

3F8569
MJK 4A 408
cw / should be a horizontal flange mounting

3F8570
MJK 4/2 360' A408
cw / horizontal flange mounting

3F8571
MJK 4A 41
ccw / horizontal flange mounting

3F8572
MJK 4/2 360' A47
ccw / horizontal flange mounting

3F8573
MJK 4A 313
ccw / flange mounting

3F8574
MJK 4/2 180' A311Y
ccw / flange mounting

3F8575
MJK 4A 409
ccw / appears to be horizontal flange mounting

3F8576
MJK 4/2 360' A409
ccw / appears to be horizontal flange mounting

4F8678
MJK 4/2 360' A410
cw / horizontal flange mounting

4F8679
MJK 4A 410
cw / horizontal flange mounting

5F7489
MJK 4B 408
cw / should be a horizontal flange mounting

5F7490
MJK 4/2 360' B408
cw / horizontal flange mounting

5F7491
MJK 4B 41
ccw / should be a horizontal flange mounting

5F7492
MJK 4/2 360' B47
ccw / horizontal flange mounting

5F7493
MJK 4B 313
ccw / horizontal flange mounting

5F7494
MJK 4/2 180' B311
ccw / flange mounting

5F7495
MJK 4B 409
ccw / should be a horizontal flange mounting

5F7496
MJK 4/2 360' B409
ccw / should be a horizontal flange mounting

5F7497
MJK 4/2 360' B410
cw / horizontal flange mounting

5F7498
MJK 4B 410
cw / should be a horizontal flange mounting

6F1082
MJK 4/2 180' B107
ccw / should be base mounting

6F1083
MJK 4/2 180' B109
ccw / should be base mounting

6F1084
MJK 4/2 360' B48
cw / should be a horizontal flange mounting

7F6532
MJK 4/2 180' C313
ccw / flange mounting

7F6533
MJK 4/2 360' C412
cw / horizontal flange mounting

7F9922
MJK 4/2 180' C107
ccw / base mounted

7F9923
MJK 4/2 180' C109
ccw / base mounted

7F9924
MJK 4/2 360' C48
cw / horizontal flange mounting

7F9929
MJK 4C 408
cw / horizontal flange mounting

7F9930
MJK 4/2 360' C408
cw / horizontal flange mounting

7F9931
MJK 4C 41
ccw / horizontal flange mounting

7F9932
MJK 4/2 360' C47
ccw / horizontal flange mounting

7F9933
MJK 4C 313
ccw / flange mounting

7F9934
MJK 4/2 180' C311
ccw / flange mounting

7F9935
MJK 4C 409
ccw / horizontal flange mounting

7F9936
MJK 4/2 360' C409
ccw / horizontal flange mounting

7F9937
MJK 4/2 360' C410
cw / horizontal flange mounting

7F9938
MJK 4C 410
cw / horizontal flange mounting

8F5871
MJK 4/2 360' C411
ccw / horizontal flange mounting

9F1165
MJK 4/2 180' C319
ccw / flange mounting

9F2513
MJK 4/2 360' C49
ccw / horizontal flange mounting

9F4475
MJK 4/2 360' C45
ccw / horizontal flange mounting

9F5113
MJK 4/2 360' C420
cw / horizontal flange mounting

My parts book has the 4S6470 as the "complete magneto" to order. All the Bosch versions are listed as "individual parts only" or something to that effect.

American Bosch mags came in A, B, C, D models.....all pretty much alike.
I show the 410 models as having a part number ICK 2A4-30 deg. impulse coupling assy and assigned to the industrial engine D6

The 408 models have a ICK 2A2-30 deg. impulse coupling assy and are designated for the D6 tractor.

Yes, towards the end of the D6"U" run they switched to the WICO mags and used them on into the D6B production. (To me they are not built as well as the AB units.)

Thanks guys for the answers and information and I appreciate all the mag numbers you put together KidNV. Nice job! That will come in handy. I was able to fix my impulse problem by robbing the weights and plate from a six cylinder Bosch I had laying around that came off a MM power unit. I was surprised they used the same parts. Thanks again, Rick

Ok,
So Pulled the cap off my magneto MJK 4/2 360C-47 and the pulled the rotor off. It disintegrated in my hand. I’m thinking this is the source of my pony engine problems. Now the rest of the rotor (Brass piece) seems seized in the shaft. I pulled on it and pulled the whole gear shaft out. I’m worried that there was a snap ring and washer on the back of the shaft that popped off and is now lost inside the mag, so far have not found it. It could be stuck to the magnets inside the.

I also have a MJK 4/2 180 A311 with all good parts.

Question: Can I swap back flanges, drive gear, points, etc. and run the 4/2 180 clock wise or will it not spark rotating the opposite way, maybe due to the windings in the armature?

Thanks in advance!
Jeff T

I misread above. Since both part numbers are odd, they are both ccw, so there should be no roation issues.

So the real questions are:
1. Am I missing a retaining ring/washer?
2. Can I swap rear flangs and use the other mag?
3. Timing for reinstall?

Thanks again,
Jeff T

hello tarquj ,the sheet i have for the Bosch magneto says all the parts are the same expect parts 2,3,4B and 67B,
MJK4/2 360 is clockwise rotation and MJk4/2 180 anti clock wise rotation ,
http://img685.yfrog.com/gal.php?g=79698014.jpg
.
bruce oz

Hi Bruce, thanks for the reply,
I didn't get a chance to tinker with the Mags last night, but I'll try again tonight.

Are you sure about this? this contradicts what kidNV states above although he also caveats his list by "I can not state that I have made no errors, this took some time (too much time). " But, according to this:

-MJK 4/2 180' A311Y ccw / flange mounting
-MJK 4/2 360' C47 ccw / horizontal flange mounting
This supports my theory that only the mounting flanges are different (with a few minor casting changes, etc.), once flanges swapped I should be good to go... the 180' vs 360' looks to be the flange designation while the last numeric character odd vs even correlates to ccw vs cw rotation. This is consistent through the entire list.

One more thing about the 180 mag, we used the cap from the 180 on the 360 years ago. We had to cross the plug wires to get it to run, but couldn't remember if that was the stock config or if it was the difference in mags causing the need for cross wiring. I'm wondering if that is another difference in 180 vs 360... Another note, the 180' came from an earlier dozer (no clue about serial number, was in a bone yard) than the 955 which was running with the 360'.

Jeff T

hello tarquj sorry for the miss info,i did miss reading the c47 when i was reading the mag info😖mokin:.kidNV info is better than mine .it is hard picking up mag info with so many models fitted to the cats ,in the link it looks like the flanges are diff part like you say .bruce oz

No worries Bruce, I appreciate the feedback.
Any ideas on how the 180' mag will react when I bolt it into my machine? I am going to try it and see anyway, but it would be nice to know ahead if i have to debug.

Either way, I note my results here.
jt