Can anyone tell me how the heck to get the glow plug electrical leads off a Kubota powered bobcat 743? The front one heats but the rest feel cold. Can't get the leads off to remove the plugs, they don't have a hex nut on them looks like a knurled thumb nut of some kind.
Generally Kubotas have a knurled nut, with a straight screwdriver slot, cut offset from center., on top. Vice grips with knurled jaws, should get them off, in a space pinch...
That's not a screwdriver slot, that's the self locking design
Thanks for that. I've tried a pair of pliers but need more strength to turn the nut. I got one to turn a few degrees but it's turning the electric connection with it, afraid of breaking it. Do you put a screwdriver into the slot to unlock the self lock?
Worth a try. Sounds like you may need to replace them all anyway, so not too much worry about saving them?
I may have to replace the plugs but I'd like to save the conductors. I live on a small island and parts are a pin to get.
Been a while since I worked on the Kubota in the Bobcat at work but seemed to recall the slot in the nut that held the connectors on the top. Did some looking on Google and found this picture the shows what ours looked like. Just a round nut with the slot for a screw driver. Here is a better picture: That last picture is actually off a web page selling glow plugs for a 743 BobCat. https://picclick.com/Bobcat-Glow-Plug-Set-743-643-743B-Diesel-171363413935.html#&gid=1&pid=1
The "self locking" was a joke. They're just a funny looking knurled nut. Spray a little penetrating oil on and if they break off the glow plug then you need a new glow plug, which you might need anyway if they're burned out. If the one turns but takes the electrical connector with it, loosen it as far as the wire allows and the electrical connector should pop loose from the nut with a little pressure, maybe a small screwdriver or right angle pick if you're worried about it.
Delmer FTW.... looks like some have wrench flats under, you just need a flat ignition wrench to slip under the connector. And no that's not another joke, ignition wrenches are, or rather were a thing.
Penetrating oil is your friend. Time and heat in machinery aren't .
Thanks for the photos, I managed to get a little further into the engine area and loosened the three that are not going to require removing the injector lines. I used some stubby screwdrivers. I took out the three plugs and tested them, they all work. Glow red hot. I cleaned everything up and reinstalled. Hopeful it was just some corrosion on the plug nuts and connectors.
That one behind the injector lines is a PITA. I had to do that on my 743. I ended up replacing them all as since they wouldn't glow when hooked to a battery. Hopefully your injector lines come loose easier than mine did.
I just became suspicious it wasn't the head that was hot at the number one glow plug but the connector on the wire from the relay. I will remove the wire and replace the ring connector, there may be some corrosion in the connection causing resistance and thus heat. If that doesn't work I will change out all for plugs. Thanks for the suggestions. Al
The new connector solved the problem. Thank you. Al