I need help with an old TD14. This is a farm machine as a result gets used very little. Started and ran last year, parked and won't start now. Now i have no fire at plugs in the gas position, how do you check a magneto? Not sure where to start at this point.. Thanks Ron
I'd say your points are probably dirty, clean them up and set the gap(.020") pull the cap and rotor (clean them too), should be 3 screws holding a cover to access the points. I've used a piece of business card for feeler gauge with good results. Should be one wire off the side of the mag, it gets grounded to kill, make sure it's not grounded to run. If that all fails your coil may be bad, you can cobble a oil filled auto coil into the system with a little wiring.
Points could be the problem but when sitting for that long I've seen moisture in the distributor more often than not cause the no start issue. Pull it off and use a bit of ether to blow out the cap and distributor. I've also seen the rotors pick up a lot of green stuff that causes problems.
The points should spark while cranking it. If they don't go no farther. Be sure all ether is cleared out. It can have explosive cap busting results. Rotor can arc through to distributor shaft. Once drilled a hole through a cap to use a standard coil. Ran the coil wire through it, not on a TD.
If it has the old hard coil mag it won't have a external coil and doesn't need one. As noted check the ground out circuit, check the cap and points. Is a start impulse coupler in the old mags, if it does not kick over during cranking won't give enough advance either to start.
Wow, Thanks for all the info. I replaced cap and set the points at about 13thousands (per a book on a td 14A). I could not find a wire from the magneto that might be grounded, is that underneath the mag are where else might i look? Just to be sure I understand, youshould be able to see an arc at the points with the dist cap off? If not where do I go next?... Thanks Ron
If the coil is bad, I used the magneto on an old TD9 simply for the points and wired in a external coil and ran it off of battery power.
Oops my memory failed me .020 is the point gap on the later dist models, .013 magneto point gap. Kill wire should be coming right of the side of the mag, I've seen the wire Insulation rot inside and ground to the case also.
Wow, Thanks for all the info. I replaced cap and set the points at about 13thousands (per a book on a td 14A). I could not find a wire from the magneto that might be grounded, is that underneath the mag are where else might i look? Just to be sure I understand, youshould be able to see an arc at the points with the dist cap off? If not where do I go next?... Thanks Ron[/QUOTE]
OK heres what I know now. I found the wire from the points to the condensor and the wire from the magneto. the points and mag wires apparently screw onto the condensor. However, the magneto wire reads a short to the chassis at all times which in turn shorts out the points and the condensor. Does this mean that the mag is shorted out or is there another switch that could be causing the problem? I think there is another switch somewhere that shorts the magneto to ground when in the diesel position. My lever is in the gas position, but could that be part of the problem or am I overthinking and the magneto is the problem?? Thanks Ron
If the wire has the solid ground it is not the mag at fault. Start the hand over hand on the wire, find all the switches that could possibly have it shut off, isolate and test each one. Condensers also can go bad, usually shorting to ground.
If the lever is in the gas position and the mag wire is still grounded, then the switch in the front of the manifold might not have flipped all the way over, this is caused by the shaft going thru the manifold getting sticky. Look up behind the carb and you will see a "V" piece of metal and a flat piece in the middle of the "V". Grab the V and make sure it is pulled all the way up. Then check to see if the wire is still grounded. George