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Coil Now Gets Hot- With New Distributor

mrlewp87 Jubilee was running pretty well, but had a slight wobble in the distributor shaft. I opted for a new one. Just installed it. Did my very best to set points at 0.025", repeatedly using .024 and .026 as support. New points, so feeler type gauges were ok as choice in tools.
Very curious that only now, is the coil becoming very hot to touch, where before- old worn out distributor- it would be slightly warm after 1.5 hrs. running time!?
Can't say what brand points/ condenser are in the new distributor. I have a new set (brand name?) likely of better quality. Use them? Or is this almost certainly related to the points set too closely? Isn't that a cause of too hot a spark, higher current? Or what?
Timing, also I'd guess. The Jube still doesn't like idling below 600 RPMs, so I focus on 1200, and timing at 20 dgrs. BTDC. (manual says 19.5). Coil still hot.

Jim Loveridge My first thought would be a bad condenser. For some reason it's drawing too much current. I don't think ignition timing would have anything to do with it. If it's not the condenser, and you if you have an ohm meter, remove the primary wire that goes to the coil and the wire to the condenser and check for any stray ground at that terminal when the points are open. Let us know.
BobV_KS Hot coil is due to excessive current. If condenser is open (lost internal connection) it would not affect current. If it were shorted or leaky (high resistance short) it should cause no or weak spark.

Another way to do Jim's test is to put a piece of heavy paper or plastic between the points, then turn switch on and check voltage on the wire between points and distributor. It should be near battery voltage, if it is low you have a short or leakage on distributor side of coil. Check feed through insulator and points/condenser connections in distributor

Is this a 6 or 12 volt system? If 12 volts with 6 volt coil and a resistor between coil and switch check that resistor is not bypassed.

Jim Loveridge Neat trick Bob, the paper between the points. I'll try to remember that. My thinking on an open condenser is that without it, the points are arcing just a bit and could cause the coil to get hot.
BobV_KS Jim, yes, I find the paper (or any non electric conducting material) to be easier than trying to turn fan to open points.

I don't believe an open condenser itself will cause coil to overheat. Battery supplied coil current flows when points are closed, and with open condenser there will not be enough secondary voltage from the coil to fire the plugs, so the engine will not run. With engine not running the only way to heat the coil is with distributor side of the coil grounded, either through closed points or unwanted short circuit and the switch left on.

mrlewp87 (Rem: new coil, new distributor- w/new points & condenser)
**12V converted system, 12V coil. Max current calculated to be just under 4 amps. Believing hi current as the cause of hot coil, I opted for max. gap settings all around::
.......... I started with plugs; cleaned and re-gapped to max-
0.028, instead of 0.025.
.......... points; far too tight on the 0.025 feeler! Re-gapped to 0.026 (attempted) Repeatedly found the gap to close some after tightening screws. Finally, using the 0.030 gauge, I got a good feel on the 0.026- after! turning of the screws. Oh, to set them at correct position; with plugs pulled, turned the _____? (thing which drives pistons. Ha. Crankshaft?) NOT using fan blades, as I've read to do, but questioned. That belt would be way tight if that could happen. There's a nub on front of the lower pulley wheel(?). It has slots to insert a thin shaft, such as (lacking an actual tool) a long screwdriver, which I used. Made real easy to turn the drive-shaft, but only forward.
........... Timing; an odd thing happened. After setting the points, I easily found 5 dgr.s, and saw the 8 dgr. mark I put there last fall. I began turning the shaft in very slight increments, so I could spot and re-mark at least the 20 dgr. point. I lost sight of any markings at all. So I reversed my tugs on the shaft (....hey!!**# :-O ) thinking I'd gone in the wrong direction. Never found them again! Gave up and decided to move on. Engine started up fine. Put timing light to it, and there were the vanished timing marks.
Again, I went with 20 dgrs. / 1200 RPMs. Ran the Jube for 20 mins. and the coil was just warm, not hot ! Thinking the points gap was primary cause.

Bob G I have eyeballed a lot of points. 0.001 or 2 one way or the other will not make the coil run hot. To have a hot coil, you would have to have a direct short and then it probably would not run.

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