no start JD B

[nutsoverJD]

I have a B that won.t start. It is a styled 50's something serial # past 201000 I opened the case to verify timing marks on both flywheel and gov. Mag seems to trip at LHEO when mark on flywheel is inline with the case mark. I bought it not running but did get it to run before. It ran ok but won't restart. It has spark I cleaned the carb. checked timing and reset mag. I don't have LH impulse mark on the flywheel just LHEO and TDC with degree marking. If I put the TDC marks Inline with the case mark piston is not at TDC. I time it as the manual say feel for compression and stop at marks on flywheel cover. However, my LHEO mark is at the case mark. Should I feel compression when turning to this position? Should the TDC mark be inline with my flywheel cover as the manual says??Others on this page suggested switching the plug wires. I haven't done that yet

 

[Jim.ME]

Here is a link to his thread in the Restoration Forum for background to date.

No start JD B

 

[NoDakInMN]

One of the things that make it hard to diagnose a starting issue is not knowing everything that is happening or the person's level of knowledge. So let's start with a couple basics because if you overlook those and skip ahead to more advanced issues you can waste a lot of time on what could be a simple fix. First, are your plug wires metal core? I've seen people put on plug wires meant for HEI systems on mag ignitions and they simply don't work. Second, is your mag impulse tripping as it should? You should be hearing a click each time the mag fires. The impulse speeds up the mag at cranking rpms to generate adequate spark because cranking speed alone isn't adequate. Third, if you crank the engine for a bit without it firing, are the spark plugs wet when you remove them? If they are dry, that points to an obvious carb/fuel issue.

When troubleshooting, especially with a piece of equipment whose history is unknown, it's best to start with the simple things and work your way up through a process of elimination. This allows you to build a base of knowledge of what is working on the equipment and what isn't, which is useful in diagnosis because often times it is a combination of factors causing the issue.

 

[Mike(NEOhio)]

If the timing marks on the crank to cam and cam to governor are lined up, the notches in the mag coupling should be horizontal when the LEFT HAND IMPULSE on the flywheel is aligned with the mark on the cover. Are you sure the flywheel is in the correct position to the crankshaft? If it is then ignore the LH EXHAUST mark. TDC is TDC and doesn't matter for mag timing, the mag fires both plugs on every revolution. And that's where the mag (or distributor points open) should trip for starting. The running advance is built in. Seems to be a lot of confusion in beginners trying to time these.

 

[nutsoverJD]

One of the things that make it hard to diagnose a starting issue is not knowing everything that is happening or the person's level of knowledge. So let's start with a couple basics because if you overlook those and skip ahead to more advanced issues you can waste a lot of time on what could be a simple fix. First, are your plug wires metal core? I've seen people put on plug wires meant for HEI systems on mag ignitions and they simply don't work. Second, is your mag impulse tripping as it should? You should be hearing a click each time the mag fires. The impulse speeds up the mag at cranking rpms to generate adequate spark because cranking speed alone isn't adequate. Third, if you crank the engine for a bit without it firing, are the spark plugs wet when you remove them? If they are dry, that points to an obvious carb/fuel issue.

When troubleshooting, especially with a piece of equipment whose history is unknown, it's best to start with the simple things and work your way up through a process of elimination. This allows you to build a base of knowledge of what is working on the equipment and what isn't, which is useful in diagnosis because often times it is a combination of factors causing the issue.

I will check the wires.

 

[nutsoverJD]

If the timing marks on the crank to cam and cam to governor are lined up, the notches in the mag coupling should be horizontal when the LEFT HAND IMPULSE on the flywheel is aligned with the mark on the cover. Are you sure the flywheel is in the correct position to the crankshaft? If it is then ignore the LH EXHAUST mark. TDC is TDC and doesn't matter for mag timing, the mag fires both plugs on every revolution. And that's where the mag (or distributor points open) should trip for starting. The running advance is built in. Seems to be a lot of confusion in beginners trying to time these.

The flywheel looks like it has been taken off to me but the counterweight on flywheel is at three o'clock when piston is at TDC

 

[used red MN]

Are you sure the flywheel is in the correct position to the crankshaft?

Mike, I gave him some unofficial (never worked on a JD two cylinder) help on his thread on the Restoration forum” Can the flywheel actually be put on incorrectly. I looked for information on this and what I found claimed that there is a wide indexing spline that wouldn’t allow this. What does a real JD man say about this?

 

[rustred]

The flywheel looks like it has been taken off to me but the counterweight on flywheel is at three o'clock when piston is at TDC

that is why i asked you to check for the mag tripping at tdc. on compression. but you get told other wise. so be it.

 

[Watthour]

...The running advance is built in. Seems to be a lot of confusion in beginners trying to time these.

Wouldn't that also be the "starting retard" built into the mag drive? Also known as Mag-Lag?

Then again, "starting retard" could be misconstrued as an operator who grabs the flywheel before disengaging the clutch, placing in neutral, and not opening the fuel petcock. Been there.

 

[used red MN]

that is why i asked you to check for the mag tripping at tdc. on compression. but you get told other wise. so be it.

To clarify, rustred is referring to his reply in the Restoration thread. By TDC he means the physical position of the piston not the timing marks. This may possibly be done by placing a wire or screwdriver in the spark plug hole to feel for the position if that will work on these. And by this the OP can possibly be able to determine that the flywheel is on wrong or if possible the wrong one. I am only saying this because there may be a possibility a styled and non-styled are different. I don’t know for sure, I am just throwing things out there that may help the OP. Some photos of what he has might help, often times the trained eyes can see things those with minimal experience do not.

 

[ET]

The tdc mark on the late B is a punch mark on the hub of the flywheel. It lines up with a vee mark on the bottom of the center hole in the flywheel cover.

 

[Mike(NEOhio)]

Mike, I gave him some unofficial (never worked on a JD two cylinder) help on his thread on the Restoration forum” Can the flywheel actually be put on incorrectly. I looked for information on this and what I found claimed that there is a wide indexing spline that wouldn’t allow this. What does a real JD man say about this?

My A has a V stamped on both ends of the crank and on the flywheel and my H has the same. See the pictures. I've also heard some have a rivet in one spline or a dead spline so it can go only one way, but never seen one. The V on flywheel is under the nut. W29 appears on the flywheel and the clutch driver toward the bottom, which leads me to think they were balanced as a unit at the factory. Can't see it here but there is a punch mark on the boss opposite the tapped hole that will align with the mark on the cover's center hole at TDC so you don't have to take the cover off, only the center plug.

 

[Mike(NEOhio)]

The flywheel looks like it has been taken off to me but the counterweight on flywheel is at three o'clock when piston is at TDC

Why does the position of the counterweight concern you? Check for the markings on both ends. These things are really pretty simple but can confuse newcomers. See my reply to used red's post. You said the timing marks on the gears all line up, BUT, where they line up is NOT TDC. Go by the flywheel LH IMPULSE. At that point the mag drive slots should be horizontal. With the mag off turn the cup CCW while holding it in a vice, not in your hand. You will feel the spring load up then a loud snap when it trips. That is from lag angle built into the cup and gives the running advance. Go another turn till you feel it hit the spring again. Keep it there and hold the whole mag so the lugs go into the slots and don't worry about the position when it seats in place. Then turn it forward till you can put just the bolts in. With the LH IMPULSE lined up, turn the mag slowly till it trips and tighten it there. Now it's timed.

 

[nutsoverJD]

Thank you for all the information. I will try again with all the information I received. My flywheel doesn't have a LH impulse marking.

 

[Mike(NEOhio)]

Thank you for all the information. I will try again with all the information I received. My flywheel doesn't have a LH impulse marking.

Show us a picture please.

 

[Mike(NEOhio)]

Thank you for all the information. I will try again with all the information I received. My flywheel doesn't have a LH impulse marking.

Can you show us a picture? My A has a dot on the heavy rim of the flywheel where the lettering is and I've never seen a letter series flywheel without it.

 

[nutsoverJD]

I will look closer the marks I do have are very hard to read