Magneto Problem?

[Andy Dutkiewicz]

I have a Farmall A that I replaced the mag coil & condensor becuase when it would run for about 1.5 hrs it would quit on me. I took the mag out to replace the coil and put it all back together and timed it, and it started but was running pretty rough, which is what I expected. I went to adjust the mag to smooth it out and it quit running. Now when I try to start it it will not start at all. I checked the mag again and when I try to time it by lining the up the mag and rotor in the number 1 position I can not get to line up. It seems like the mag and rotor are either in the 12pm or 2pm position and I can not get it to line up with number one. My timing marks are on and #1 pistion is at TDC. Is there a chance the magneto could have jumped and wil lnot line up anymore? There is a tremendous amount of play in the mag when I try to line it up but I just can't seem to get it in time. Am I doing something wrong. Feeling frustrated, this has gone on for a couple of weeks and I cannot get my tractor running again. I appreciate anyone's help and wisdom. Thank you

 

[Nebraska Cowman]

Did you have the little gears out that drive the rotor? they have to be timed too.

 

[Andy Dutkiewicz]

No, I did not know about that. How do you do that?

 

[Cienna]

How about new points and condenser----These are as important in a magneto as they are in an ignition system.

 

[Andy Dutkiewicz]

I did replace the condensor and the points are in good shape, I regapped them to the correct gap, so I know I am good there. I am more curious as to how to retime the little gears for the rotor? Do I need to take the mag apart to retime the gears?

 

[Bret4207]

Andy, if you had the gears out you need to find the manual and set them according to instructions. Had a devil of a time finding that info for a Cat pony mag I have, but there are usually marks to go by if you can locate the info.

 

[Andy Dutkiewicz]

I did not have the gears out all I did was take the entire mag/distributor of the tractor and aligned the mag and rotor the best I could. That would make sense to me why that mag slot would not line up correctly! I apologize if I am slow but if I understand everyone correctly I have to take the portionunder the distributor apart and line up the gears on the inside too. I do have the manual and will look through that as well. Thank you. I appreciate it the information.

 

[El Toro]

You need to remove No1 sparkplug near rhe radiator and bring No1 piston to TDC on the compression stroke. Hold your thumb over the plug hole while a helper hand cranks the engine until you feel pressure against your thumb.

Once you feel pressure drop[ a long plastic straw on top of the piston. You watch the straw rise while the helper keeps slowly cranking. When the straw quits rising you should be at tdc on the compression stroke.

Remove the cap on the mag and see where your rotor is pointing. If it isn't pointing to your No1 plug tower you need to pull the mag and rotate the rotor so it is. Hal

 

[Anonymous-0]

I did that but when #1 is at TDC and the timing marks line up on the flywheel, I pulled the rotor and try to line up the rotor I can not get it to #1, it will only get as close as the 12:30 position or the 2pm position. Someone mentioned earlier that I need to time the small gears near the rotor, do I need to pull the distributor off the mag body and line up timing marks there? teh last time I did exactly as you said it did start running, but it was rough. When we went to adjust the mag the tractor quit and would not start again. I feel like I am missing some thing.

 

[Bob]

First, take off the little cover just under the rotor (2 screws) and see if the gears are correctly timed. Instructions are in the Blue Ribbon Service Manual at the link below.

Make sure the engine is rotated to the #1 TDC position at the end of the compression stroke.

Then, (before installing the mag) rotate the mag BACKWARDS so the impulse doesn't catch so the rotor points to the #1 high-tension tower. Set it so the points have just closed going backwards/begin to open when it's turned forwards.

Install the mag and the wires (in firing order).

Be SURE the kill switch is set to "OFF".

Rotate the engine exactly TWO turns, approaching #1 TDC SSLLLOOOOWWWWWLY, and verify that the impulse snaps AT (NOT before) TDC.

http://www.cleancomputes.com/Cub/Blue%20Ribbon%20Service%20Manuals/GSS-5035%20Service%20Manual%20Magnetos/index.html

 

[Andy Dutkiewicz]

Thank you!

 

[barnE]

Did you have wires off? Also any tower on cap can be number #1 if you identify as such and use correct firing order and rotation. Dave

 

[Bob]

So... did you yet 'er runn'in?

 

[Andy Dutkiewicz]

No. I took the mag off the tractor yesterday and I am going to check the distributor gears as I feel I may be a tooth or 2 off as I tried to retime the mag and got the same result, it fired up ran rough and when I went to move the mag to smooth it out it quit and now I can not get it running. I need to see if the dist gears are off or if the mag is wore out and needs to be replaced. It is the original. Thanks for your help and wisdom, I do appreciate it. I will let everyone know once I get it running. Thanks again