35MF Gas -coil resistor

MF35 4 cyl Continental gas that I seldom start.
I am quite certain that the last time it ran for any amount of time that it was fine. That was about a year ago.

I tried to start it and it smoked from the external resistor for the coil and would not start.

Went to Automate and told the parts guy what the resistor was for and that it is the same resistor used on late 1960s and early 1970s Chryslers. He said he knew just what I was talking about and gave me a "Standard T-series" #RU4T resistor.

I put the new resistor on and it started right up and ran for about 3 minutes then quit like the key was shut off. It will not restart now. I felt of the external coil resistor and it was hot.

What is likely my problem? Should I try another resistor?

Thanks, Greg
 
1st I suspect u will need a new set of points, and I'd change the condenser as well, they will go bad just sitting. ck the coil, I guess this is a 12volt tractor? id get the correct resistor from a supplier like tractor supply if there is 1 in ur area. the coils will also breakdown just sitting..
Doc
 
good suggestion. just a thought , I changed the coil on my IH 240 several yrs ago, put a 12 volt coil with an internal resistor, haven't changed the points since. again, just a thought
Doc
 
Yes, it is a 12 volt tractor.
The points look good -almost new. The points, rotor button and cap have evidently had very few hours put on them. I assume the condenser was replaced at the same time.

-Would it have run good for a few minutes than stopped dead if it was the condenser?

-So do I need a 12 volt coil with a built in resistor or will any 12 volt coil work? Will Tractor Supply have the coil with a built in resistor?

-What kind of damage would I do if I wired straight to the coil (bypass the resistor)that is on it and drive it about 2 miles to get it to my garage to work on it? I assume it will start if I do this.
 
T/S should have the parts u need. as to why? I have seen many scenarios in the past. make sure u have 12 volts at the coil, if not there is a wiring issue. condensation forms on ing parts, it turns white when warmed by voltage being applied to the circuit. if there is no pitting on the face of the points u should be able to clean them with a small piece of card board, such as the box top off the coil box. ck the point gap as well, if memory is good its between .016-.020, this should at least get er going
Doc

you should get a 12 volt test light , if you don't already have 1. I suggest a good quality1 not an elcheepo.
 
Will do on getting the correct coil and cleaning/setting the points
for starters.

Will it hurt to bypass the resistor and drive it about 2 miles with the
coil that is on it?- assuming it will start like this.

I appreciate y'all, Greg
 
as to by-passing the resistor, u can try that, but if the coil is bad, u wont get very far would be my guess. a 12 volt coil with internal resistor would be a better choice , and probably fix ur issue. again I can not stress enough test the system, ck voltage to and from the coil. u could find the plugs fouled instead of an ing problem. I hope some of this helps.

Doc
 
Hey Greg, I had a problem lke that with my 135 4 cyl
last week took me a week to figure it out. i had
bought a new coil thinking that was my problem to
start with. short of the story is i had to put a
external resistor at the coil, was getting to much
fire at the points and burnt them up actually some
of the plastic on the points had slightly melted. i
got a resistor from NAPA with 1.82 Ohms that took
the volts down going to the coil to about 9 volts .
works and runs great now. Hope this helped
 
If you have a 12 V electrical system, check your coil's primary resistance. If it is ~3.6 ohms, you don't need a resistor. The resisitor is used for current limiting of the primary. The max allowable current for long point life is ~ 4 amps.Ifth eprimary resistance is ~ 1.6 ohms, then you do need a resisitor. Reistors will get hot as they dissipate power to reduce the current.
 
If you have a 12 V electrical system, check your coil's primary resistance. If it is ~3.6 ohms, you don't need a resistor. The resisitor is used for current limiting of the primary. The max allowable current for long point life is ~ 4 amps.Ifth eprimary resistance is ~ 1.6 ohms, then you do need a resisitor. Reistors will get hot as they dissipate power to reduce the current.
 

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