Ignition rotor.

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Qtr Milr
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Ignition rotor.

Postby Qtr Milr » Fri May 27, 2016 7:01 pm

Sorry for all the questions!! I'm used to working on muscle cars. This is my first ever tractor. I was checking out everything under the hood now that it's off and checked the cap and rotor. The rotor is so loose that it's wearing into the bottom terninal of the cap. I pulled the bracket that holds the rotor in place and the rotor basically fell off. Shouldn't it be tighter on the end of the shaft?? I can put the rotor on any way I want. Isn't there something to index it on the shaft??
Thanks again for any and all help!!

Thackery
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Re: Ignition rotor.

Postby Thackery » Fri May 27, 2016 7:14 pm

Yes the rotor, and matching shaft have a flat side. There is nothing that actually holds it on it just slides on and tha cap traps it in place.
Thackery
1953 Cub, Sickle Mower, 42" Mower, Cultivators, 189 Double Plow, 54 Blade, Grader Blade
1968 Lo-Boy w/1000 Loader, 1957 Lo-Boy w/FH, FH Disc, FH Potato Plow.

Jim Becker
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Re: Ignition rotor.

Postby Jim Becker » Fri May 27, 2016 7:28 pm

Lets back up a little here. This is a '49 isn't it? It would have started with a magneto. If it still has one, the rotor turns on a smooth round shaft. It is driven by a small pinion gear. Timing the rotor requires aligning timing marks on the rotor and the pinion. Since the rotor goes 1/2 the speed of the pinion, their are 2 ways to align the marks. One is right, the other 180 off. Read more details here:
viewtopic.php?f=140&t=83108

If it has been converted to battery ignition, a different story applies.

staninlowerAL
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Re: Ignition rotor.

Postby staninlowerAL » Fri May 27, 2016 8:31 pm

Jim has you covered on this one. I reread your posts and I'm not really sure what you are dealing with on the ignition system. Pictures might help but before you go jumping from one thing to another a definitive assessment of your tractor's electrical system will save you a lot of time, agrivation and probably expense also. Just my thoughts. Stan
EDIT: You can get all the specifics by downloading the service manual GSS 1012 from the manuals link at the top of this page.

Qtr Milr
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Zip Code: 46818

Re: Ignition rotor.

Postby Qtr Milr » Fri May 27, 2016 8:39 pm

Yes it's a 49. It still uses the magneto. I just assumed that the rotor had some way to index it like a car. There is so much slop in it I'm surprised it ran as well as it did!! I'll get the tune up parts ordered and go from there.... Now that I'm not sure exactly which way the rotor was pointing I have more fun to figure out!! I sure appreciate all the help.
Thanks,
Scott

Jim Becker
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Re: Ignition rotor.

Postby Jim Becker » Fri May 27, 2016 9:32 pm

Qtr Milr wrote:. . . Now that I'm not sure exactly which way the rotor was pointing I have more fun to figure out!!

Two ways, both require aligning the timing marks on the rotor and pinion:
1) Guess. Put it in one way and see if it will start. If it doesn't, reinstall the rotor 1/2 turn around.
2) Turn the engine to TDC compression on #1. Install the rotor pointing to #1 (about 2 o'clock) so the marks are aligned.

Both of these shortcuts assume the plug wires are in the right places.

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Glen
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Re: Ignition rotor.

Postby Glen » Fri May 27, 2016 9:36 pm

Hi,
I think Thackery gave info for a Battery Ignition rotor, so if you have a magneto, it is different. :)

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Re: Ignition rotor.

Postby Eugene » Fri May 27, 2016 9:37 pm

Qtr Milr wrote:The rotor is so loose that it's wearing into the bottom terminal of the cap.
This happens after long term use. The metal tang on the rotor and the distributor cap center terminal wear out. Both the rotor and distributor cap should be replace.

This is not to interject on the original discussion topic.
I have an excuse. CRS.

Qtr Milr
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Re: Ignition rotor.

Postby Qtr Milr » Sat May 28, 2016 6:27 am

Great info!! Thanks again. I'll be replacing cap, rotor, wires and plugs. Ought to run like new!!

Bill E Bob
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Re: Ignition rotor.

Postby Bill E Bob » Sat May 28, 2016 7:00 am

Remember to get a rotor for a magneto and you might check the pinion for wear, if still original it should also be replaced. (BTW-they aren't cheap)

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Glen
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Re: Ignition rotor.

Postby Glen » Sat May 28, 2016 8:15 pm

Hi,
Clean out the old grease and dirt in the area around the rotor gears, and then grease the rotor and pinion gears when you put it together. :)

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clodhopper
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Re: Ignition rotor.

Postby clodhopper » Mon May 30, 2016 9:51 pm

you might want to sit down before you look at the price of a mag rotor and pinion....

Qtr Milr
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Re: Ignition rotor.

Postby Qtr Milr » Wed Jun 01, 2016 7:50 am

Too Late!! Oh well. My rotor is a crispy critter and the cap is the same......


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