No start JD B

[nutsoverJD]

I have been trying to start my grandsons B (he is one years old). I have checked all timing marks from gov to crank. all is good. there is 110 psi compression in both cyl. I checked valve lash and readjusted as needed (wasn't off much). I have a 25degree mag.in it. it is an all-fuel machine. Do I need a 35degree mag? Had it running twice for a short time. Seems to have good spark I cleaned the Carb. Tried either and it will backfire to the intake. I moved the mag some both directions didn't help. Any suggestions will be appreciated. I will buy new plugs, what do you recommend there is champion D21 in there now.

 

[Mark-Ia]

If you've had the mag off or plug wires off, Try switching the plug wire in the cap if it's back firing through the carb

 

[nutsoverJD]

If you've had the mag off or plug wires off, Try switching the plug wire in the cap if it's back firing through the carb

I verified if the #1 cyl was firing at the correct time. but I will try thanks

 

[Fixingfarmer]

Your d21 champion or if you can’t find that Autolite 386. Properly gapped .030 and torqued to 32 to 35 ft lbs.

 

[nutsoverJD]

thank you

 

[used red MN]

I verified if the #1 cyl was firing at the correct time. but I will try thanks

Hello nutsover, welcome to YT! I will admit I don’t know all the ins and outs of timing the ignition on a two cylinder Deere but I will offer this. First off you’re new here, I/we have no idea how much “proof is in your pudding”! You say you checked it is firing #1 cylinder at the right time, but for that to be valid here you need to tell us exactly how you did it. Pull the both spark plugs and plug a spark plug onto #1 wire. Clamp it in a jumper cable that is grounded to the tractor on its other end. Crank the engine does it spark if so continue. Now hold your finger or thumb in the #1 spark plug hole and turn the flywheel feeling for the push of compression. When that is felt continue to turn the flywheel until the L.H. Impulse passes the mark, this should happen in less than a half a turn, this is when the number one plug should fire.
The piston can be at top dead center twice through the 4 cycles once at the end of the exhaust stroke and a turn later at TDC of compression. If you are just checking to see if it fires when the flywheel impulse mark passes the pointer you only have a 50/50 chance of being correct.

 

[nutsoverJD]

Hello nutsover, welcome to YT! I will admit I don’t know all the ins and outs of timing the ignition on a two cylinder Deere but I will offer this. First off you’re new here, I/we have no idea how much “proof is in your pudding”! You say you checked it is firing #1 cylinder at the right time, but for that to be valid here you need to tell us exactly how you did it. Pull the both spark plugs and plug a spark plug onto #1 wire. Clamp it in a jumper cable that is grounded to the tractor on its other end. Crank the engine does it spark if so continue. Now hold your finger or thumb in the #1 spark plug hole and turn the flywheel feeling for the push of compression. When that is felt continue to turn the flywheel until the L.H. Impulse passes the mark, this should happen in less than a half a turn, this is when the number one plug should fire.
The piston can be at top dead center twice through the 4 cycles once at the end of the exhaust stroke and a turn later at TDC of compression. If you are just checking to see if it fires when the flywheel impulse mark passes the pointer you only have a 50/50 chance of being correct.

I follow the procedure in the manual. However, it is confusing as my flywheel only has LHEO marking and then there is TDC and some degree markings' When I put it at TDC the piston isn't in the correct position. I opened the top case cover and verified the timing marks they line up as according to the manual. I do the thumb over the plug hole to check for TDC and it lines up with LHEO. According to the manual my timing marks are on the starter cover and flywheel when it is in this position the LHEO lines up with the mark on the side of the case it all seems to be in the correct position I also double checked and corrected the governor timing marks and set the mag according to the manual. I hope this explains what I checked several times am i missing something?

 

[used red MN]

I hope this explains what I checked several times am i missing something?

I just wanted to make sure you are aware of the two different positions that a piston can be at TDC within the 4 strokes. LHEO stands for Left Hand Exhaust Open, which I believe is there for the purpose of setting the valve, but I am not sure. So what all is up with the tractor? It ran before you worked on it? You had it apart and are doing restoration work on it? You should post this on the YT John Deere forum in the Manufacturers section. Give the information I just asked for.. “tell the background story” on it. You will get more responses there.

 

[rustred]

If you were playing with the May u are out of time. Just by saying backfire and you moving th Ed msg back and forth. No sense worrying about plugs or degrees. Time it first , get it running then proceed on the next problem. You don’t need to be worrying about flywheel marks. Feel for compression in number one. Then keep turning the flywheel slowly till the mag trips and stop right there. Then see if the piston is at top dead centre. Wires could be switched at dist. Plus no mention of when it ran last or why it’s not starting now. ? Confirm the timing first.

 

[Fixingfarmer]

What year B? Both early and early styled process should be the same I haven’t had to get into a late one but I’d assume cover gets pulled off.

Don’t worry about TDC for the time being.

If you are sparking at LH exhaust open that is incorrect you want to have it spark at LH impulse on the flywheel

Very possible it will run if you try switching the wires like all above have suggested that mag was off be 180 off and the wasted spark will be very close to the left exhaust valve open spot on the flywheel iirc

Most of your wico x will be 25 degree advance as I understand it. It should not matter the ones I have are wico X they will run with a wico C as well.

If your v marks on the crank and the governor gear inside line up you can’t help but be close to timed or 180 off at the mag. Flip the wires to try. If it bothers you pull the mag and rotate then put the wires back

 

[nutsoverJD]

I just wanted to make sure you are aware of the two different positions that a piston can be at TDC within the 4 strokes. LHEO stands for Left Hand Exhaust Open, which I believe is there for the purpose of setting the valve, but I am not sure. So what all is up with the tractor? It ran before you worked on it? You had it apart and are doing restoration work on it? You should post this on the YT John Deere forum in the Manufacturers section. Give the information I just asked for.. “tell the background story” on it. You will get more responses there.

thank you I will do that

 

[nutsoverJD]

If you were playing with the May u are out of time. Just by saying backfire and you moving th Ed msg back and forth. No sense worrying about plugs or degrees. Time it first , get it running then proceed on the next problem. You don’t need to be worrying about flywheel marks. Feel for compression in number one. Then keep turning the flywheel slowly till the mag trips and stop right there. Then see if the piston is at top dead centre. Wires could be switched at dist. Plus no mention of when it ran last or why it’s not starting now. ? Confirm the timing first.

OK I will. That is what confuses me is I check for compression stoke with finger in the plug hole and feel compression on my revolution to LHEO. and piston is on TDC

 

[nutsoverJD]

What year B? Both early and early styled process should be the same I haven’t had to get into a late one but I’d assume cover gets pulled off.

Don’t worry about TDC for the time being.

If you are sparking at LH exhaust open that is incorrect you want to have it spark at LH impulse on the flywheel

Very possible it will run if you try switching the wires like all above have suggested that mag was off be 180 off and the wasted spark will be very close to the left exhaust valve open spot on the flywheel iirc

Most of your wico x will be 25 degree advance as I understand it. It should not matter the ones I have are wico X they will run with a wico C as well.

If your v marks on the crank and the governor gear inside line up you can’t help but be close to timed or 180 off at the mag. Flip the wires to try. If it bothers you pull the mag and rotate then put the wires back

OK Thanks