Model 50 ignition

Brian Tyree · Posted: Thu Nov 29, 2012 2:48 pm Post subject: Model 50 ignition

I am having a problem with my 1953 Model 50 that is driving me nuts! Help. The tractor sat for years and the motor was stuck. I pulled the head and got the cylinder unstuck, put it back together and got it running. The problem, It runs on the right cylinder. the left is not firing at all until I unplug the right cylinder and then it starts running on the left. It will even start on the left if I have the right plug wire off the plug. The minute I reattach the right plug wire the left stops firing. This tractor has a distributor.When I put a inductive timing light on either cylinder it seems like it is firing. It seems like it will run on either side, but only one cylinder at a time. thanks Brian

Bob Harvey · Posted: Thu Nov 29, 2012 4:22 pm Post subject: Re: Model 50 ignition

Only guessing , but, there must be something goofy with your distibutor. How's the cap? Are the points opening equally on each cyl. ? Is the timing correct? As you already know, makes NO sense. HTH

Brian Tyree · Posted: Thu Nov 29, 2012 6:35 pm Post subject: Re: Model 50 ignition

I know, It makes no sense. I have traded the cap from my model A. It didn't change anything. I keep trying to think of some reason why this could happen.

F-I-T · Posted: Thu Nov 29, 2012 7:50 pm Post subject: Re: Model 50 ignition

greenmech · Posted: Thu Nov 29, 2012 8:02 pm Post subject: Re: Model 50 ignition

Just guessing here. Could have a manifold leak and getting just enough gas to run one cylinder? Ron Mn.

F-I-T · Posted: Thu Nov 29, 2012 8:19 pm Post subject: Re: Model 50 ignition

Paul_IN · Posted: Fri Nov 30, 2012 4:31 am Post subject: Re: Model 50 ignition

Have another coil to try? Maybe its weak and can"t build up enough energy to fire both cylinders.

Brian Tyree · Posted: Fri Nov 30, 2012 4:56 am Post subject: Re: Model 50 ignition

I will try another coil later today. It has a newer coil on it now, one made to run without a resister. I will go to a straight 12 volt coil. It is a Delco distributor.

John T · Posted: Fri Nov 30, 2012 6:08 am Post subject: Re: Model 50 ignition

Its the SAME points, coil and condensor and rotor tip that fires BOTH cylinders so you might try a new cap and rotor or at least do a critical visual to look for moisture, cracks or carbon traces etc. Look carefully at the rotor and where it fits down on the shaft for carbon or other indications of shorts.

Check the points gap on BOTH high cams and insure theres no distributor shaft wobble

Id run it in the pitch dark to look for tell tell arcing like plug wires etc

Got another set of wires you might try, maybe its a plug wire problem (arcing may show up easier in the dark).

On the vacuum leak the other gents mentioned with her idling spray carb cleaner or WD 40 etc all around the manifold base and carb to manifold junction and around the carb to see if it makes it smooth out and/or speed up, if so you found a vacuum leak leaning her out

John T

34gpa · Posted: Fri Nov 30, 2012 8:05 am Post subject: Re: Model 50 ignition

I would change the condensor also,had an A that did something like that,it will be the cheapest thing you replace. Have had them do some funny things over the years. Good luck

Brian Tyree · Posted: Fri Nov 30, 2012 11:47 am Post subject: Re: Model 50 ignition

I have changed the condenser, built new spark plug wires,coil wire, and installed a coil from a 6V Norton Commando. It was handy. Nothing has changed. I swapped the distributor cap from my model A. I haven't tried the rotor yet, but will do that. It still runs nicely on the right cylinder and is not running on the left until I take the right plug wire off. Then it will run on the left. It has the 2 barrel carb. and a delco distributor. This tractor may yet become yard art!

WTW · Posted: Fri Nov 30, 2012 11:50 am Post subject: Re: Model 50 ignition

Brian, Not to question your knowledge but, I have to ask. when you say left cylinder is missing you are referring to the flywheel side? Right being the pulley side. The reason I ask this is you normally never hear the right side hit/fire at an idle until a load is applied or a plug wire is removed. Will it miss under load as well? If you have not replaced both plug wires do so. If by chance a plug wire had an open, spark may take the path of least resistance and jump in cap creating a confusing situation. Would be pretty confident problem is not coil, condenser, or points.

Bob Harvey · Posted: Fri Nov 30, 2012 2:27 pm Post subject: Re: Model 50 ignition

I thought that too, but it would mean a faulty mnfld to head gasket - it is a twin choke carb and the carb would have to be working only on 1 side --POSSIBLE !!

Bob Harvey · Posted: Fri Nov 30, 2012 2:29 pm Post subject: Re: Model 50 ignition

Brian, see my reply to greenmech ---maybe ???

Brian Tyree · Posted: Fri Nov 30, 2012 3:31 pm Post subject: Re: Model 50 ignition

I very much appreciate all of the suggestions. When I talk about the left side, it is the flywheel side. Also I know when it is actually firing or not. The cylinder does not get even a little hot. The right side gets normally hot, burn your fingers hot. When I pull the right plug wire it starts running on the left and the cylinder gets hot quite quickly. Either side will run with out the other. It even idles quite well. The right seems to run a little better.

Allis Chalmers	Case	Cockshutt	Farmall IH	Ford 8N,9N,2N	Ford
H. Ferguson	John Deere	Massey	Minn. Moline	Oliver	All The Rest