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Farmall A won't start.

M

Mr. Farmall

Member
My 1946 farmall A won't start. Compression is good, getting fuel, not flooding, timing is good, and the spark checker sparks. It has a electronic ignition kit. When I start it, it seems to fire once and not fire again. I heard that GM ignition modules when they fail sometimes still work right when cool, but stop working once they heat up. I wonder if my Pertronix module is experiencing a similar failure, fires a couple of times and fails? Also heard a failing ignition can still fire a spark checker, especially with a higher volt coil like the Flamethrower coils.
 
nothing like points and condenser.you can have the worst set of points and as long as you have a gap and clean contacts , u can always get the engine running. with electronic ignition u are done when it quites working.
yes the G M modules used to quite when hot and once cooled down would still run. you also had to make sure you had the heat silicone applied under it to transfer the heat away.
 
Spark checker is only good for those who do not know how to really check for a good spark. Only spark checker i have ever used was hold the plug wire close to the engine block about a 1/4 inch off. You should get a nice blue/white spark that jumps a 1/4 inch gap. NOTHING beats that way and no spark checker will tell you how good the spark is all they do is tell you that you have a spark be it good or bad just that you have it
 
Why the electronic stuff put the original mag back on and go my mower engine i built 20yrs ago used a mag i had cleaned up ect it has ran all that time starts eery time they just work 60pluss yrs old and still will provide many more yrs of service. Some think they need the new fangled stuff then have problems this modern electric stuff does not always solve the problem. Are the bushings good in your dist good ect. When you put the dist on the bench hooked to a batt and wire going to all 4 plugs does it fire good. You can drive it with a var batt drill and check in all rpms if it passed all tests it should work on the engine.
 

This tractor has always had a IH distributor on it, which as far as I know is factory original. I don't think it was ever a mag tractor as it is a late A.
 
Have you double checked that the plug wire are in the right order, if you have spark and all else then it could be the dist cap wires are off by a hole or 2
GB in MN
 
(quoted from post at 12:30:18 05/08/16) All FARMALL As came with a mag dists were never factory on the A.
Click to expand...

While this is true there was how ever a factory/dealer package to change to battery ignition PN 353938 R91
GB in MN
 
Yes that would have been in around 49 long after the A went out of production. Mags still were available till in the 50s
 

Well it had a distributor when my Dad bought it back in 1990 and it wasn't new looking then. If it was swapped it was done a very long time ago and the mag is long since gone with whatever the previous owner did with it. This A has factory electric start, generator (replaced with GM alternator by me), and lights. I always been told distributors were an option by 46.

A rebuilt mag would cost more than 4 electronic kits, and I don’t have a old mag for a core exchange rebate as it was long gone before my family got the tractor.
 
(quoted from post at 22:07:25 05/08/16)
. . . I always been told distributors were an option by 46. . . .
Click to expand...
46 is simply wrong. The A never came with battery ignition. It wasn't available for the Super A until at least mid-1950.

This is, of course, irrelevant to your current problem. Follow up on the suggestions already given.
 
(quoted from post at 13:46:42 05/08/16) Have you double checked that the plug wire are in the right order, if you have spark and all else then it could be the dist cap wires are off by a hole or 2
GB in MN
Click to expand...

I checked the wires ad they are in the correct timing order, 1-3-4-2.
 

Well I guess the two options for me are either revert the IH distributor back to points or buy other Pertronix kit as generally electronic ignitions are vary reliable. Perhaps aftermarket electronic ignition isn't quite as reliable as OEM systems in cars. A mag swap, especially with having to eat a core charge isn't an option due to high expense. That is besides my unfamiliarity with mags and bad experiences with them on lawn mower engines.
 
I always carry a spare engine with me!! Seriously,
you can buy a good used mag for around $100 with
no core. I would just put points back in your
distributor and go . Either will last a lifetime with
only minimal maintenance.
a226109.jpg
 
(quoted from post at 23:08:26 05/08/16)
Well I guess the two options for me are either revert the IH distributor back to points or buy other Pertronix kit as generally electronic ignitions are vary reliable. Perhaps aftermarket electronic ignition isn't quite as reliable as OEM systems in cars. A mag swap, especially with having to eat a core charge isn't an option due to high expense. That is besides my unfamiliarity with mags and bad experiences with them on lawn mower engines.
Click to expand...

Before I purchased a new Pertronics kit I get an adjustable gap spark tester and see if your current kit is working right. With the adjustable gap tester you can set a gap to test how strong the spark is. if the unit will not jump a 1/8" gap it maybe bad, if it does you have another problem to find.
http://www.walmart.com/ip/Thexton-404-Adjustable-Ignition-Spark-Tester/41576155
 
(quoted from post at 23:08:26 05/08/16)
Well I guess the two options for me are either revert the IH distributor back to points or buy other Pertronix kit as generally electronic ignitions are vary reliable. Perhaps aftermarket electronic ignition isn't quite as reliable as OEM systems in cars. A mag swap, especially with having to eat a core charge isn't an option due to high expense. That is besides my unfamiliarity with mags and bad experiences with them on lawn mower engines.
Click to expand...

Before I purchased a new Pertronics kit I get an adjustable gap spark tester and see if your current kit is working right. With the adjustable gap tester you can set a gap to test how strong the spark is. if the unit will not jump a 1/8" gap it maybe bad, if it does you have another problem to find.

http://www.walmart.com/ip/Thexton-404-Adjustable-Ignition-Spark-Tester/41576155
 

So I swapped the points back in and still nothing. It is even worse since the timing light doesn't light at all with the points. The coil is a new Bosch Blue Coil. Looks like there is a short or break in the wiring somewhere.
 
Its simple to just run a wire from the battery to the coil direct and a new wire drom the coil to the dist. / points crank it over and see if it makes spark, it could be a short in the wire from the coil to the dist where it goes into the dist shorting it out.
GB in MN
 

I used a testing light on the tractor, distributor ground is good, positive power line to coil is good. The off switch works.
 

Think I may have found one problem, the side terminal on the distributor body isn't isolated when the points are open, even with the ignition switch off. I assume that side terminal should be dead when the points are open?
 
Yes that could be the problem, if I get a chance to look a my "B" I'll see how it is insulated.
GB in MN
 

I did some more testing, the side terminal is isolated with the points open when the ignition is on. Tried the spark checker and no spark. This is weird that the module fired the coil some while points doesn't fire it at all.
 
Have you cleaned the points? a point file and then spray them with contact cleaner or carb cleaner and see if that helps.
GB in MN
 

Power is getting through the points, and it is also getting through the positive line from the ignition switch. Before I removed the Pertronix module I tested it, and 12 volts went through it, and when I rotated the engine to when a magnet was over the module, voltage dropped to 0 like it should. I wonder if the new coil I bought is defective?
 

I did static test of the coil with a multimeter, primarily resistance is 3.9 ohms and secondary is 7.7 ohm. But I guess this isn't proof positive that the coil is good.
 
A couple of questions, has the tractor been converted to 12 volt using a Delco alternator? If so is it a one or three wire one? Is there a ballast resistor installed? Have you tried a new or different condenser?
GB in MN
 
(quoted from post at 20:15:34 05/12/16) A couple of questions, has the tractor been converted to 12 volt using a Delco alternator? If so is it a one or three wire one? Is there a ballast resistor installed? Have you tried a new or different condenser?
GB in MN
Click to expand...

Yes it has a Delco alternator which is a 3 wire model. There is no resistor, as the coils I use have built in resistors for use with the Ignitor module. Have not tried a new condenser yet, the current one is several years old but wasn't used much as I converted to electronic ignition not long after replacing the points and condenser.
 
Hi did you have it running with the electronic system? You can remove the wire from the -side of the coil that goes to the dist. then put your spark tester in the coil tower and with a jumper wire connected to the - coil terminal just touch it to the engine monumentally and if the coil is good there will be spark then connect the wire from the coil to the points and with the points closed open them and close them with a small screw driver and there should be spark from the coil if not the points are not making good contact and need cleaning.
 

It ran well for several years with the electronic kit, then one day it suddenly won't start, been fighting this over a month now.
 
Ok so when it wouldn't start you suspected the electronic unit, I think you posted that you have weak spark with the electronic unit? Maybe its ok and its the dist cap and or rotor are bad? Just trowing out ideas, another question about the alternator setup does it have a diode to prevent the igniton from working when the swith is turned off or is it using a resistor? I have seen where a double resistor was supplied one side was for the ignition part and the other was to reduce voltage for the coil if those 2 get reversed by mistake the voltage is dropped to where the coil can barely produce spark again ideas. I would not give up on the electronic system but first need to try and get some kind of spark.

I was thinking about my previous post and a a bet way to check the points and coil would be to just remove the wire from the - coil terminal turn the engine over so the pointd are closed turn the ignition switch on an just touch the points wire on the coil - terminal with the spark tester in the coil tower it will spark if the points are making good contact if no spark clean the points.
 
(quoted from post at 17:04:13 05/13/16) Ok so when it wouldn't start you suspected the electronic unit, I think you posted that you have weak spark with the electronic unit? Maybe its ok and its the dist cap and or rotor are bad? Just trowing out ideas, another question about the alternator setup does it have a diode to prevent the igniton from working when the swith is turned off or is it using a resistor? I have seen where a double resistor was supplied one side was for the ignition part and the other was to reduce voltage for the coil if those 2 get reversed by mistake the voltage is dropped to where the coil can barely produce spark again ideas. I would not give up on the electronic system but first need to try and get some kind of spark.

I was thinking about my previous post and a a bet way to check the points and coil would be to just remove the wire from the - coil terminal turn the engine over so the pointd are closed turn the ignition switch on an just touch the points wire on the coil - terminal with the spark tester in the coil tower it will spark if the points are making good contact if no spark clean the points.
Click to expand...

I replaced the coil first, when there still wasn't a spark I then suspected the module. So far the points are even worse than the module since that had a weak spark every so often while the points are producing zero sparks.

I don't believe the alternator has either a diode or resistors, tested it last night and there is no current through it with the ignition switch off. It does have a built in solid state regulator.

I will go try your suggested test but I am suspecting my replacement coil is a dud.
 
Very easy and a no special tools needed to test a coil. Hook the - side of the coil to a battery and then take a wire and touch the battery then pull that wire back off. When you do that you should get a spark from the center wire that your holding close to the coil body
 

OK I performed that test and it did spark. Next I reattached everything and hooked up the spark checker inline with cylinder 1 and it lit up. Then I tried the timing light which still doesn't light consistently.

I got got a question, if the cam timing gear sheared it's key, could that throw the timing way off without any external signs. Or would a free spinning timing gear squelch really badly?
 
Well anything is possible with these old tractors, remove the dist cap and crank the engine over and watch the rotor see if turn turns smoothly and completely in 360* if you have a crank that would be good to use if you want remove the spark plug so it will crank easier then check that the firing order is right number 1 on forward most cylinder and go on thur all 4 cylinders if that checks out I'm thinking the dist cap & rotor and maybe the plug wires could be suspect.
 

I checked the timing. Cranked the engine to TDC for cylinder #1. The rotor was pointing to cylinder #1 so the timing seems ok.
 
Get a voltmeter and check that there is 12 volts at the coil + terminal with the ignition switch on.
 
(quoted from post at 19:57:32 05/12/16)
I did static test of the coil with a multimeter, primarily resistance is 3.9 ohms and secondary is 7.7 ohm. But I guess this isn't proof positive that the coil is good.
Click to expand...
.7 ohm's on the secondary side can't be right. Do you mean 7.7K (7,700) ohm's?
 
(quoted from post at 12:20:22 05/17/16)
(quoted from post at 19:57:32 05/12/16)
I did static test of the coil with a multimeter, primarily resistance is 3.9 ohms and secondary is 7.7 ohm. But I guess this isn't proof positive that the coil is good.
Click to expand...
.7 ohm's on the secondary side can't be right. Do you mean 7.7K (7,700) ohm's?
Click to expand...

All I know is one source says that the Bosch blue coils should have a secondary reading around 7.5.
 
(quoted from post at 19:57:32 05/12/16)
I did static test of the coil with a multimeter, primarily resistance is 3.9 ohms and secondary is 7.7 ohm. But I guess this isn't proof positive that the coil is good.
Click to expand...

All I know is one source says that the Bosch blue coils should have a secondary reading around 7.5.
Click to expand...
've never heard of a coil secondary that is within a few ohms of the primary.

The number you state isn't correct. What resistance scale are you using or is an autoranging DVOM?
 
(quoted from post at 05:53:16 05/18/16)
(quoted from post at 19:57:32 05/12/16)
I did static test of the coil with a multimeter, primarily resistance is 3.9 ohms and secondary is 7.7 ohm. But I guess this isn't proof positive that the coil is good.
Click to expand...

All I know is one source says that the Bosch blue coils should have a secondary reading around 7.5.
Click to expand...
've never heard of a coil secondary that is within a few ohms of the primary.

The number you state isn't correct. What resistance scale are you using or is an autoranging DVOM?
Click to expand...

It isn't a auto range meter. This coil does have a built in resistor, the electronic ignition kits need coils with 3 ohm resistance so the module doesn't burn out. I looked at several sources for the specs on this coil which Bosch says is supposed to be around 3.4 primary, 7.79 secondary and the readings I posted are close to those. This is a 12 volt coil, not a IH 6 volt. I am not an electrical expert so if there are issues with what Bosch says I don't have answers.

I did check the voltage for the power line to the coil and 12 volts is getting to it.
 
NO such thing as a coil with a built in resister. The difference in a 6 volt coil and a TRUE 12 volt coil is how they are made/wound
 
(quoted from post at 21:26:27 05/18/16) NO such thing as a coil with a built in resister. The difference in a 6 volt coil and a TRUE 12 volt coil is how they are made/wound
Click to expand...

It is a true 12 volt coil, and the electronic kit is set up for 12 volt, negative ground. Pertronix, the manufacturer of the kit says to use a coil with a built in resistor, as the kit needs minimum 3 ohm resistance in the coil to prevent overload and module failure. Both Pertronix and Bosch state their coils have built in resistors.
 

"I did check the voltage for the power line to the coil and 12 volts is getting to it." That's good so the coil is getting full voltage, and you posted that there was spark from the coil tower when the wire was touched monetarily but when its all together no constant spark, that make me believe that there is a problem with the rotor or the dist cap or both. Here's what I would do clean the points good and try a new dist cap and rotor.
GB in MN

PS the spec's on the Bosck coil are
Bosch Blue coil (Brazil)
0 221 119 027 or 00012 (VW 043 905 115C)
turns: 150-1 (unverified)
primary: 3.4 Ohm
secondary: 7.79 kOhm[/url]
 

So I have been thinking what else the problem could be. After the last time I ran the tractor, I replaced the manifold gaskets because it was leaking smoke out of an exhaust port. Decided to take the manifold off again to see if there was something wrong. The old gaskets were silver and the new ones were grey. Took the manifold off and saw that the grey gaskets when crushed, pushed into each other and formed a overlap which would be a high spot right in the center of the manifold. Could such a weird overlap induced high spot cause enough of a vacuum leak to prevent starting?
 

Replaced the intake gaskets, still won't start. Took the Zenith carb off, took it apart to see if anything was was wrong with it, there is a rip in the bowl to body gasket but the rest of the carb looks fine, there was fresh fuel in the bowl. The floats seem to be ok. Looks like it will take a week for the replacement carb gasket to arrive. There aren't any IH dealers in 100 miles of me so I have to mailorder parts and wait.

This is really becoming upsetting, the tractor seems to be defying logic why it won't start. I can really see why they changed tractors over to diesel now. The grass around it is getting chest high, even if I do get it running the grass may be too tall for it to cut now.
 




Mr. Farmall I know you want to get this fixed as much as these folks want to help ya. Maybe its time to start posting pictures of the set up on your tractor as many pics of suspect areas as you can think of open some things up and lets take a look at em.They say a picture is worth a thousand words,. take some pics of that carb while you got it off.
I've seen more times than not someone spots the issue in the picture that you may have overlooked. Besides pictures you can blow them up and get a real close view of the parts in question.
If you don't know how to post pictures

#1. Click on reply to a persons post, screen will come up to log on to.#2. Put your email and password then click log in, screen will come up. #3. Now scroll down and click on upload photo another screen will appear in the small box.
#4. OK now click on were it says browse If your pictures are on the desktop you should now see them If not look to the left and click on pictures you should be able to select your picture from there. once you found the picture you want #5. Click on the picture then click open. #6.Now next to were it says browse click upload. It may take a moment to load the picture once you see the picture click continue Note: the picture is in the large message square but is a sequence of letters and numbers to see it #7. scroll up and click preview. #8. Now scroll the page up again your picture should be there if all is ok #9. scroll back down and click submit, Your done Hope this helps seem like a lot but it its really not

Best of luck Byron
 
You can make a new gasket quicker. Purchase the proper size material trace the new from the old, cut the outline with a single edge razor blade or an x-acto knife and punch out the screw holes with a brass ferrule and a small hammer.

In a pinch cereal boxes also make for good gasket material.
 
Here's a thought maybe the dist shaft bushing is worn so bad that the rotor and points will not work right, something to check out this happened on my 8N dist.
GB in MN
 

I checked the shaft and it doesn't appear lose. The carb gasket arrived early, installed it and double checked the float height. Still won't start. On a whim I swapped the points back out for the ignitor. With the electronic kit, the engine fired and ran for a nanosecond before stopping, then would not start again for awhile. With the points it just would not fire or run at all, really weird Going to replace the rotor and cap next in case there is a short to ground.
 
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