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Discussion Starter #1
1969 MF 135 with perkins

they sell a resistor, and the new coil I got came with one, what is the purpose of it?
The trouble I am having is a transient power loss, I think its in the electrical system , sometimes it goes away when it is warmed up other times it works just fine.

I am changing the coil and wires, already have done the points and condenser, new wire from ignition to coil. I have never had a resistor on the coil in the last 30 years since I got it. The last time this happened I thought it was gas and replaced the carb. and it did the same thing for a while , then it started running fine and has been for three years. BUT sometimes when it runs a while it will stall out, usually when its hotter out. then when it cools down it runs fine, I have heard that, that might be the coil

this time it was running well getting time for a tune up. but also have been fighting a burn spot on the starter winding, so I decided to replace the starter, that went well, changed the points cond, and started having trouble again,.
I was getting plugs fouling, so I changed them, and this is why I think that its ignition. I also used a strobe light to get the timing, but it was not a steady blinking, but all jerky , this is leading me to think I have some problem with ignition.

thought it might be the ign wire shorting out so I change it also.

I just got the new coil and will try that out.

if you have any clues I would appreciate and suggestions. I use the tractor all the time and its a nuisance when it is not working well
 

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If I'm not mistaken, the resistor is needed when converting a 6 volt ignition system to a 12 volt chasis ground system. The resistor reduces voltage to the coil so it doesn't burn up the ignition system.

:howdy: May want to wait for a more knowledgeable person to confirm this!
 

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Discussion Starter #3
thanks, well I put it on as is? and its running fine, hope someone will confirm this
 

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Pull the distributor cap and the rotor and then see how much you can easily rotate the distributor shaft also check for side to side movement in the shaft do this when the engine is hot and cold. I'm thinking that either the distributor gear is worn out or that the distributor shaft bushings are worn out and causing your issues


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Forgot to mention that there should be very little side to side play( almost none) the gear play will be more but still shouldn't feel like you are turning it more than like 1/16 to 1/8 inch


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certified tractor nut
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Any updates?


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Discussion Starter #8
it was the coil, as soon as I put it on it ran better than ever I noticed the old coil had written on it something like (resistor required) so I am wondering what it does, and thinking that it is important.

it is on the secondary side of the coil so it probably isn't 67 to 12 volt thing.

I had tried two different coils over the last 2 or three years but this new one makes complete ignition, which I was not getting before.
 

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Discussion Starter #9
its one of those things with a lot of clues that don't make any sense till after you fix it.
looking back I was getting a lot of carbon on the pipe and at a leak in the exhaust, and smokey when I started it and dieseling when I turned it off, with a faulty coil , that would cause those things to happen. thanks for the help. and I hope \this may help other too!
 

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Glad you got it running good again


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