It will not even pop!!!!

[MARV2015]

OK all you JD experts!
I have a 1951 John Deere "A" that I am in process of rebuilding. Big problem - It will not even pop when trying to start! It has electric starter so cranking is no problem. Checked compression and getting 60 -65 psi on both cylinders. I even have another 1941 "A" that I borrowed the carburetor off of just to see if that would help -it didn't! I did put the "71DLTX" carb on my 1941 and cranked it up! Ran just fine and even adjusted the carb when it warmed up. Put the DLTX 71 back on the 51 "A" and still nothing! Not even a sputter!
It is getting gas because I have even resorted to squirting directly into a cylinder and still -NO POP!

The spark at the plug seems to be a bit weak but it is there.
I am NOT familiar with the insides of the WICO magneto and need some guidance as to how to go about checking it out to try and get a bigger spark. I DO NOT want to swap the mag off my 41 which is running quite well!

Any suggestions??? The last time this tractor was running was about 40 years ago and with what I have done to it - I think it should just jump right up and run! I'm a bit perplexed!

 

[David G]

I would run a point file through the points, then run dollar bill through them after, get a good spark and it will start.

 

[RandyB(MI)]

Unless it all appears new , you may as well get new points and condenser and rotor as they are usually wobbley/worn.Check cap for cracks and make sure the two contact lugs aren't all worn/torn up. Clean plug terminals with steel woll or such. Clean/scuff the contact poll on coil and corresponding spring steer finger in cap. If someone at one time put carbon core wires on it they are more than likely junk by now. Get solid core wires and non-resistor plugs. Make sure you can hear the impulse "clicking" in mag when you roll it. Won't start if not (unless you pull it). Hopefully you have drained that 40yr old fuel. It won't burn.

 

[old]

Bet the points need to be cleaned up. Simple as pulling the cap off and the point will be in plain site. I have to do that any time I want to run my JD-B but it sits for years with out being run and is hand start

 

[Ben So Tex]

Make sure the wires are in the correct hole. may have been swap in the last 40 years by sightseers.

 

[buckeye al]

Being a '51 it likely has an X series mag on it. They're a good mag but sitting for years usually causes point troubles. Mags are more demanding of their breaker points than distributors. That is... if the points aren't working their best they cause more degradation of the spark than similarly ailing points in an electric distributor! Mags are also more demanding of proper gap than distributors.

First thing I'd do is remove the distributor cap (not the whole mag, just the cap) and do EXACTLY as Old says below! Been there & done that way too many times to count! A points file will remove any hard crunchy, big, ugly stuff & the dollar bill dragged through the closed points polishes them to clean off the small bits of residue left behind by the filing operation. I don't recommend sand paper or emery cloth because they leave grit behind like slag on a weld & the grit doesn't conduct electricity. Check the gap to see it's .015".

Last of all if it's actually been 40 years since the tractor ran and this mag has not been serviced in the same time period, I'm surprised you see any sparks at all!

An X mag should give you a nice BLUE spark across a 3/16" gap every time the impulse trips without fail.

Since you say you don't even get a shotgun type kerblam out the stack, it hints to a mag issue. That or the wires are not cutting the mustard. If your plugs are in question, why not switch the plugs between the '51 and the '41 which you say runs nicely? I kind of doubt they're the problem because fouled plugs often spark when not under pressure that's when one of the lost sparks (when the valves are open) makes 'em pop out the stack telling you all about it! Those reports being missing, I'd get the screwdriver & points file if Old didn't beat me there!

Hope it's this simple.

 

[James Howell]

"<font color="#6699ff">[b:654c4848f0][i:654c4848f0]Any suggestions???[/i:654c4848f0][/b:654c4848f0]</font>"

You might also consider adjusting the magneto timing.

Reviewed the [b:654c4848f0]OPERATOR?S MANUAL No. OM-R2003R JOHN DEERE MODEL ?A? SERIES (SERIAL No. 648000 AND UP) TRACTOR[/b:654c4848f0] in the [b:654c4848f0]IGNITION SYSTEM[/b:654c4848f0] section under the [b:654c4848f0]Installing Magneto on Tractor[/b:654c4848f0] topic on pages 34-35.

"[i:654c4848f0]Installing the magneto after it has been removed from the tractor can be done easily as follows: First remove the spark plug on the flywheel side.

Place your finger over the hole and rotate the flywheel in the running direction until you feel a pressure of air in the cylinder. Continue turning the flywheel slowly until the punch mark stamped on the flywheel hub, lines with the ?V? grove on the flywheel guard.

In this position the slot in the coupling on the governor shaft will be horizontal.

Next secure a short piece of wire and insert one end in the upper terminal of the distributor cap on the magneto, bend the other end around within 1/8-inch of some metal part of the magneto.

Hold the magneto solidly in the same upright position as when mounted on the tractor.

Grip the driving lug on the impulse coupling firmly and turn the impulse slowly in a left-hand direction (counter-clockwise). Stop instantly when impulse trips and spark occurs between end of wire and magneto frame. When impulse trips, driving lugs on the magneto coupling will be in a horizontal position.

Replace magneto and gasket on the governor case, making sure the impulse coupling lugs engage slots on the governor drive coupling.

A gasket must be used between bolting flanges. After tightening the two cap screws firmly with fingers, rotate the top of the magneto toward front of tractor as far as possible. Then rotate the flywheel one complete turn and line the punch mark on flywheel hub exactly with the ?V? groove on the flywheel guard.

Now tap the top of the magneto toward the rear of the tractor a little at a time until the impulse trips.

Tighten the cap screw holding magneto to governor case and install spark plug cables. Left hand spark plug cable must be installed in upper distributor cap terminal.

[b:654c4848f0]Caution: Whenever adjustments are made on the tractor engine, remove the spark plug cables from spark plugs and battery ground cable to prevent accidental starting.[/b:654c4848f0][/i:654c4848f0]"

Hope this helps.

 

[jeo46]

Compression is low, but make sure mag is timed properly-could be 180 degrees out of time. Revere wires at mag and
see if it pops.

 

[46chief]

I don't think mthat is enough compression to fire. I have a cub motor that runs 100 lbs on each cylinder. What is the compression of your other tractor?

 

[MARV2015]

You just gave me another thing to check. I'm not sure but i will check it!
For now - I took the Mag completely off the 51 A and found the base unit with the flyweights and spring were all loose and not even assembled! The shaft would turn but nothing else happened. So - after looking up the parts illustration for the Mag - I managed to get it back together. Now - I will try to get a spark from it before i put it back on the tractor! Hopefully things will then come together and work properly.
More info tomorrow!

 

[BushogPapa]

Aa-ha'''ya went and made it MAD at ya.....!!!!

Happens at the worst times, too...

Do not accept "Weak Spark" are "Good Enough"...the spark should SNAP like it would BITE ya GOOD..

 

[MARV2015]

Well I have just acquired another Magneto and I will see if this makes a big difference when I install it. Probably get to it later today! More to come on this!

 

[MARV2015]

HOOOOOOORAY!!!!!!!! The new magneto really got it fired up!!!! What a sound -after all the times of hitting that starter and nothing happening - it fired up and ran the float bowl dry! Good sound -even acted like it wanted to get out of the barn and pull something! Just the nicest sound I could ever imagine today!
SO - now for the clean up and put all the little things back together -fresh oil and then to figure out how to make the power steering work! For now - I'm going to put the long steering column back in and just go it with out any power steering. I really want to get it running and drive it now!

 

[MARV2015]

Gee -It was short lived! The mag certainly made a difference and the tractor ran for a few minutes! I was adjusting the carburetor to smooth things out and it seemed to idle down real nice and almost smoooooth!!!! Then all of a sudden it just stopped and coasted to a stop. Kind of like the mag just went dead. I re-timed the mag and nothing - Not even a pop!
Pulled the mag and check to see if it was still firing and yep -it is! Nice blue spark! So I put everything back on the tractor and re-set the timing once again. Hit the starter and NOTHING again!
This time I pulled the plugs and noted they were very black and sooty. SO - decided it was time to stop for the day and clean up!
Soooooo- Friends ----What are your suggestions now????

 

[AlanA]

(quoted from post at 06:22:50 11/08/16) Gee -It was short lived! The mag certainly made a difference and the tractor ran for a few minutes! I was adjusting the carburetor to smooth things out and it seemed to idle down real nice and almost smoooooth!!!! Then all of a sudden it just stopped and coasted to a stop. Kind of like the mag just went dead. I re-timed the mag and nothing - Not even a pop!
Pulled the mag and check to see if it was still firing and yep -it is! Nice blue spark! So I put everything back on the tractor and re-set the timing once again. Hit the starter and NOTHING again!
This time I pulled the plugs and noted they were very black and sooty. SO - decided it was time to stop for the day and clean up!
Soooooo- Friends ----What are your suggestions now????

Clean the plugs. 8)

 

[MARV2015]

Well folks - I must say that I am SOOOOOO very embarrased!!!!
When I last posted that my "A" just stopped running while trying to tune it. I was trying everything I could get any info on this during the past week! I can now set the timing on this tractor in my sleep! Points -The same and backlash on the mag also!

I am almost ashamed to admit the problem was reeeeeeeally simple and I over-looked it all this time!
Only real thing I did was to put a gasket between the mag and the mount and -even better- I put more gas in the tank!!!!!
YEP!!!! That simple little thing -It RAN OUT OF GAS!!!

Now I have a tractor that is running and I might add -seems to run very well! I want to get the little things I have left to do all finished and get it out on the road for a little test drive. I would love to get both of my "A"s on the road together and compare them against each other.

SO - ON to the business of getting the water pump working and mounting an alternator - then get the lights working and then think about installing that other hydraulic unit!
Thank you all for your suggestions - your help - and your patience with me!