MF35 Intermittent Spark to Plugs

[WranglerBowman]

Hey all, I'm losing it right now with my 1964 MF35 Z134. I was disking my garden and the tractor just stopped for no apparent reason after using it for about an hour, no spark. Because I was racing the rain to get my garden it I ran out to TSC and bought a 12V coil and 12v solenoid and figure that should cover my bases. It started and was running and then just cut off again after only 15 mins...hmmmm...must be a fuel issue then. Started foolin with the carb, it started running again...cuts off. So I pulled the entire carb apart, cleaned everything real well, put it all back together, starts up but only runs for a bit. I've gotten used to setting this carb well enough to run but can not get the tractor to stay running. Bought all new points, cleaned the distributor...won't stay running. I'm getting good spark from the coil to the top of rotary cap, but rotary cap is not putting out consistent spark, it sparks to the plugs for a little, then stops, then will spark here and there. I took off one of the wires from the distributor and plugged into an old plug so I could see how it was sparking and the tractor runs great when it's getting spark, then all of a sudden no spark, what am it missing?

 

[SIMassey]

Hey all, I'm losing it right now with my 1964 MF35 Z134. I was disking my garden and the tractor just stopped for no apparent reason after using it for about an hour, no spark. Because I was racing the rain to get my garden it I ran out to TSC and bought a 12V coil and 12v solenoid and figure that should cover my bases. It started and was running and then just cut off again after only 15 mins...hmmmm...must be a fuel issue then. Started foolin with the carb, it started running again...cuts off. So I pulled the entire carb apart, cleaned everything real well, put it all back together, starts up but only runs for a bit. I've gotten used to setting this carb well enough to run but can not get the tractor to stay running. Bought all new points, cleaned the distributor...won't stay running. I'm getting good spark from the coil to the top of rotary cap, but rotary cap is not putting out consistent spark, it sparks to the plugs for a little, then stops, then will spark here and there. I took off one of the wires from the distributor and plugged into an old plug so I could see how it was sparking and the tractor runs great when it's getting spark, then all of a sudden no spark, what am it missing?[/QUOTE)


Ignition switch losing contact or an inline fuse loose making intermittent contact? Does the 35 have a fuse next to the key switch like the 135?

 

[WranglerBowman]

I don't remember seeing a fuse near the ignition switch and I looked over the switch and everything appears to be making contact well, but I'll pull all the wires off and clean up the connections and see if that makes any difference. I'm really starting to think that the rotar is not making great contact with the distributor cap points.

 

[SIMassey]

I don't remember seeing a fuse near the ignition switch and I looked over the switch and everything appears to be making contact well, but I'll pull all the wires off and clean up the connections and see if that makes any difference. I'm really starting to think that the rotar is not making great contact with the distributor cap points.

Internally the switch could be bad. Any splices in the wire powering the coil? Could be a break internally in the wire from the distributor to the coil or the wire to the ignition switch. 1964 was 51 years ago. Anything is suspect at that age. You've changed all the normal repair parts. Now's the time to check the rest of the components in the ignition system. Might just run new wires to eliminate the possibilities. There's not much left. Even a bare spot on a wire thats vibrating could short out momentarily causing the problem.

 

[WranglerBowman]

I checked the wire from the switch to the coil and besides the 2nd outer plastic coating peeling off, the first plastic coating around the wire is fine with no cracks or bare spots on the wire. I'm gonng to order a new distributor condensor, rotor and cap, along with cleaning the ignition switch connections. If that doesn't work I guess I'll replace all the wiring to and from the ignition switch.

 

[WranglerBowman]

So I installed a new distributor condenser, rotor, cap, and cleaned the ignition switch up...I'm getting spark from the coil to the cap...and I'm getting spark to the points beneath the rotor...but I only got a couple sparks to the plugs when I first fired up and now I'm not getting any spark to the plugs...can anyone explain what could be the issue? I've replaced the ground wire from the points to the coil also. I'm not really sure what else to look at.

 

[donhartman]

I know it is redundant ,but are you positive you have a good ground connection even from the battery ? Take them loose and rough them up . Sounds kinda like you are loosing a ground to me !

On that carburetor ....you may as well start at the top . Clean the rust from the tank ,then the tank screen onto the screen in the bowl etc . Otherwise you will keep having to get into that carb. Stuff can and will get past them screens and into the carb . Also how are the floats ? Good day Don

 

[WranglerBowman]

Yep, I've cleaned and looked over every ground I could find on the tractor to everything. I'm going to double check the points gap tomorrow morning. The floats are stained but no holes and it functions as it should. I really don't think I have a fuel issue at all and it's just getting the carb set up right. Thanks.

 

[Harry in Ky]

Don't see any mention of plug wires? You ARE I assume using the old style wires with metal core? Later style automotive wires with carbon core will not work well with points/coil ignition.

 

[WranglerBowman]

Don't see any mention of plug wires? You ARE I assume using the old style wires with metal core? Later style automotive wires with carbon core will not work well with points/coil ignition.

I'm using new wire which are copper core low ohm MF wires.

So after setting the points gap to 0.022 as specified in the manual and turning the distributor about 20 degrees I started getting consistent spark and after setting the carb at 1 full turn for the Air screw and the jet screw I actually got it to start and run. Then I spent the next 4 hours trying to tune the carb with no luck, won't stop bucking if I try to take it up a 5% slope and wants to stall. One interesting thing though is I can drive up a 30% slope IN REVERSE with absolutely no problem, no stalling runs like a champ!!! ...but I can't go forward under load. I'm thinking the float is doing something weird in the carb with the gas sloshing around in the bowl of the carb against the float, and when I throw it in reverse the gas runs to the front of the carb and the float drops. Has anyone had this happen before? How did you fix it?