Z Moline Ign or fuel problem

Hello,

Posting again after a year about the old family 1948 Z.

It had not been run in a few years before last summer I had it going briefly. I thought then (maybe still the case) of old fuel being why it has little power and seems to miss/run rough even driving about the yard.

This tractor has a magneto. J8C plugs.

This past week I was attempting to use it a bit to pull a hay rack to haul brush/branches. Not a real big load!

What seems to happen, is that it will idle mostly OK but not completely smoothly. Put any load on it and there is some missing or misfire going on. It may nearly stall. I pulled the plugs and found 1 wet one. Other 3 were dry but all had carbon on them (but not thick/crusty). Didn't have any new ones on hand but found some used ones of unknown prior use that were saved in a box so tried one of them to replace the wet one. Didn't make a difference in this problem at all. Tried pulling the wires 1 at a time to see if I could determine if there is 1 or more weak plugs/wires. Didn't seem to make ANY difference in the idle!! Pull off any 1 wire and no difference in the idle at all. Don't know what to make of that. I did see the spark was blue arcing from the wire to the plug tip if I held it near (not orange).

I am sure a set of new plugs can't hurt but not sure it would matter. I did have it running long enough to use up most of the old fuel and topped that off with a gallon or 2 of new. No change at all. So, I am not sure if this is a fuel or spark issue. Could this be wires?

thx

If it were mine, I'd put new plugs in. I'd also flush out the tank and lines to get all the old gas out. Clean the screen and make sure the gas flows fast enough out of the tank. I think you would benefit from a good carb cleaning too. If you can get it to idle OK, then put a load on it, where it coughs and sputters, if probably is not getting enough gas, or the gas is bad.

I would pull mag cover and clean and gap the points it works same as distributer and if they're off it wont run right. Here in the northeast if they sit a few months the points corrode and need to be cleaned to run.

I'd suspect a dirty carb to be the bulk of your problem. But a good tune up (Plugs, wires, and clean points) on the ignition would be worthwile also.