Electrical problem with my Cub 184 tractor

[Charlie M]

Went to get my Cub 184 ready to mow yard from winter storage and it wouldn't start. Got it up to my shop and determined there is no spark. I have put a meter on the + side of the coil and I get 12 volts there as it should. Its a 12 volt system and is designed to deliver 12 volts to the coil when starting. When I check the - side of the coil and open the points I also get 12 volts there. Shouldn't I get a lot more voltage at that point to fire the plugs? I took the points out and cleaned them, put them back and re-gapped them. Points are good with no pitting, just some darkness on the metal which filed off. I'm getting 3 ohms of resistance across the coil terminals so I'm thinking that isn't the problem. Possible bad condenser? Tractor ran good when parked last fall. Looking for some thoughts?

 

[Brownie450]

Check if there is a safety switch [have to have clutch depressed].
Otherwise possible bad condenser.
I went to get the cub cadet out this spring, & errattic firing --back fired.
Finally started & ran badly. Changed out the condenser, & no more
problems. It was an original condenser.
Jim

 

[Charlie M]

I've been doing some home work on how a condenser works in an ignition system and I think you're right about probably a bad condenser. If it is its the first time I've had one go bad so I can chalk it up to a learning experience. Mine is only a couple of years old but that doesn't mean much when talking about the quality of electrical components these days. I have a new one so I'll find out in the morning if that is the fix.

 

[Jim.ME]

Went to get my Cub 184 ready to mow yard from winter storage and it wouldn't start. Got it up to my shop and determined there is no spark. I have put a meter on the + side of the coil and I get 12 volts there as it should. Its a 12 volt system and is designed to deliver 12 volts to the coil when starting. When I check the - side of the coil and open the points I also get 12 volts there. Shouldn't I get a lot more voltage at that point to fire the plugs? I took the points out and cleaned them, put them back and re-gapped them. Points are good with no pitting, just some darkness on the metal which filed off. I'm getting 3 ohms of resistance across the coil terminals so I'm thinking that isn't the problem. Possible bad condenser? Tractor ran good when parked last fall. Looking for some thoughts?

Battery voltage on the + side of the coil and battery voltage on the - side when the points are open is correct. Simple description. The coil is like a transformer. The high-tension power from the center post is generated inside the coil from the current passing through it via those two terminals to ground through the points making a magnetic field. When the points open the field collapses and creates the high-tension power to make the spark. If you put a test light on the - terminal the light should flash as the points open and close during cranking. If there is no flashing the points aren't working, which could be a bad ground or broken wire.

 

[Mrfred54]

If your condenser is bad, good luck with a new one..... Ill bet in the last five years, I've had at least 10 new condensers go bad with in a week or less. Even tried different brands. Anymore when doing a tune up for a customer I tell them up front I will not change the condenser. All made in China shi#$#. Luckily over the last 40 years I have keep a lot of the old ones for all makes of tractors

 

[Brownie450]

I lucked into a box of Filko caps some time ago. Forget the number
but they fit 90% of the applications around the farm. They were
made in the USA.
Jim

 

[Janicholson]

I've been doing some home work on how a condenser works in an ignition system and I think you're right about probably a bad condenser. If it is its the first time I've had one go bad so I can chalk it up to a learning experience. Mine is only a couple of years old but that doesn't mean much when talking about the quality of electrical components these days. I have a new one so I'll find out in the morning if that is the fix.

I will add: almost all tractors with 4 cylinder gas engines stop when shut off with the points closed. If they are showing voltage at 12+ or- on both sides the points probably need to be cleaned up with fine abrasive paper then cleaned to remove grit. Jim

 

[used red MN]

I hate to say it, but did you happen to shut the gas off? Or maybe it leaked a little and the tank is empty.
Edit: Well reading in this more I guess you said there is “no spark” so my above answer is getting the cart before the horse so to speak. I am a big believer in testing the points with a test light while cranking to assure that it will flash as Jim.ME has recommended! This tells you they are performing as the “designed switch” in the circuit.

 

[560Dennis]

Did you pull the spark plugs out and check if the are firing ?

 

[K-Mo]

Went to get my Cub 184 ready to mow yard from winter storage and it wouldn't start. Got it up to my shop and determined there is no spark. I have put a meter on the + side of the coil and I get 12 volts there as it should. Its a 12 volt system and is designed to deliver 12 volts to the coil when starting. When I check the - side of the coil and open the points I also get 12 volts there. Shouldn't I get a lot more voltage at that point to fire the plugs? I took the points out and cleaned them, put them back and re-gapped them. Points are good with no pitting, just some darkness on the metal which filed off. I'm getting 3 ohms of resistance across the coil terminals so I'm thinking that isn't the problem. Possible bad condenser? Tractor ran good when parked last fall. Looking for some thoughts?

This may not be your problem, but maybe a low battery. I have experienced it multiple times. After sitting through the winter, the little C60 will spin right over with a low battery, but the battery is too low to fire the plugs. Put a charger on for 5 minutes and it's good to go. Experienced on both 154 and 184. You said you measured 12 volts. A fully charged 12 volt battery should measure about 12.6 volts.

 

[grandpa Love]

If your condenser is bad, good luck with a new one..... Ill bet in the last five years, I've had at least 10 new condensers go bad with in a week or less. Even tried different brands. Anymore when doing a tune up for a customer I tell them up front I will not change the condenser. All made in China shi#$#. Luckily over the last 40 years I have keep a lot of the old ones for all makes of tractors

On the flip side of your experience.....we have bought at least 50 condensers ( for 50 different tractors, over 3 years) from Napa and never once had a bad one. I would bet it's actually a different issue and the condenser gets the blame. Either that or I'm just lucky . Napa numbers are on my shop wall.

 

[560Dennis]

Suggest clean the distributor rotor contact and distributor cap contact s , helps

good Point

 

[Mrfred54]

On the flip side of your experience.....we have bought at least 50 condensers ( for 50 different tractors, over 3 years) from Napa and never once had a bad one. I would bet it's actually a different issue and the condenser gets the blame. Either that or I'm just lucky . Napa numbers are on my shop wall.

I have actually reinstalled the old condensers on some tractors to make them run right. Then put the new one back in and they run like crap. I've now have a good old condenser that I have a wire soldered to the clamp with a alligator clip on the end to ground it and hook the condenser to the distributor wire for testing

 

[John T]

Mornin Charlie, you asked:

When I check the - side of the coil and open the points I also get 12 volts there. Shouldn't I get a lot more voltage at that point to fire the plugs?

With the points OPEN you should see battery voltage on the coils output (to distributor) NOT more, same as voltage on the coils input (from battery and ign switch)

With points CLOSED you should NOT see any voltage as a good set of closed points takes that to ground

A total shorted out condensor or its wiring causes no spark (try unhooking it and see if she fires???) while a total open still allows a spark just weaker..

If you work through my Troubleshooting Procedure it can help funmd the cause of no spark. Often points are the problem while a bad condensor can cause no spark

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T

 

[Charlie M]

I fixed the problem this morning. Went to NAPA and got a new condenser, installed it and the tractor started right up. First time I have ever had one go bad and it was a on-line purchased condenser installed about 3 years ago so I had a bit of a knowledge gap on the issue. All 12 of my tractors now have a condenser from NAPA and all have worked out of the box and not failed in use yet. Maybe just luck but until my luck runs out that is the only place I'm buying points and condensers. Thanks to everyone on input to the problem.

 

[John T]

I fixed the problem this morning. Went to NAPA and got a new condenser, installed it and the tractor started right up. First time I have ever had one go bad and it was a on-line purchased condenser installed about 3 years ago so I had a bit of a knowledge gap on the issue. All 12 of my tractors now have a condenser from NAPA and all have worked out of the box and not failed in use yet. Maybe just luck but until my luck runs out that is the only place I'm buying points and condensers. Thanks to everyone on input to the problem.

Thanks for the update and congratulations. A mag rebuilder told me over half of the new condensors he buys check bad grrrrrr

John T