Sparkplug Adapter

Why were these adapters on 2 of my sparkplugs? I took them off and screwed the plug back into the hole.
Ferguson TO20

Well I tried to post a pic and that didn't work. There were 2 adapters on 2 of my plugs by some previous owner, I am just curious why?

I believe what you have are call "anti- fouler". Supposed to keep plugs from oil foul.

those cylinders may be pumping oil, will foul the plugs in short order, those extensions will help for a while if that is the problem as it keeps the plug further out of the oil.

normally its only a band aid, soon you may have to do engine work.

another and I think better solution is, if you only have one cylinder that is pumping oil, buy a "hot" range plug, designed to fire in a higher concentration of oil,
many times you can keep the old motor running for a long time with one of those.

by it having two, that very well may mean you have two cylinders pumping oil.

time will tell, I would not throw them away, just yet.

buy a few extra plugs and keep them in the tool box with a wrench to change a plug in the field. it starts missing, pull the old plug install a new one and be on your way.

note to file: if the motor still has fair to good compression, then the motor may have been hot at one time, when they are allow to get hot, sometimes the oil rings will get stiff and no longer scrap the oil off the cylinder walls as necessary, so oil gets by.

you may need watch the temp gauge and be sure the radiator and water pump are working properly.

Ok thanks for the information. I thought they may have been some type of thread adapter but after removing them the plugs screwed right in. I will keep a check on fouling. I had some bad idling and running that I pretty much corrected with a new carb. I had bought a kit for the carb I had, but when I got it apart there were pieces missing. After struggling with the rebuild I elected to buy a new one. I was still getting some sputtering so I checked the plugs, wires and spark. The 2 plugs with the adapters were not fouled with oil but badly with soot. I cleaned them and took the adapters out and the tractor runs much better.

non fouler extensions
can purchase different lengths I suppose.