Glowplug won't tread all the way in?

[sloth646]

M1008.

Searched no answer to my problem.

Decided to replace the glow plugs for the first time today. All the plugs on the drivers side came out and new ones went in fine. Then the passanger side. First plug came out fine, but when I put the new one in it treaded in fine for 3 or 4 revolutions then it gets real tight and is only threaded in half way. I don't want to crank on it real hard because im afraid it will break. Any ideas on what I should do or try.

Thanks

 

[sloth646]

Also, I have 2 extra wires on my passanger side with the spade connectors on them. Theirs a third wire but its been cut. Anyone come across these extra wires. All 3 wires are in that same wire bundle on the side of the block that the glowplug wires are with. Any idea what they go too.

Thanks again

 

[my86m1009]

not sure about the wires,first make sure the glow plugs are exactly the same like the thread length and threads. go to a hardware store and get a tap that is the same thread as the glow plug. Use it to clean the threads out in the head, try your best to keep the metal out of the combustion chamber. Don't force the tap in, just try and clean the old threads out. keep us updated

 

[sloth646]

Here are some pictures of what I am talking about:

Thats as far in as the glowplug will thread in.

The random 3 wires which are all connected to one of the big orange wires which I believe have some thing to do with the glow plugs. 1 of these wires was connected to the 4th glow plug passenger side. Other random wire is wired in with the rest of the glowplug wires.

Old glowplug (left) new glowplug (right).

 

[BIG_RED]

I think that the glowplugs are metric thread. But they are quite fine threads. Be sure to have the right tap to chase your glowplug holes with. And cover the tap in grease to collect all the little pieces of metal it knocks out of the threads. I believe that the orange wires are the power supply wires for the glowplugs. No idea what those little wires are for.

 

[sloth646]

I will try the Tap tomorrow and see what it does. from looking at my picture and looking at the other plugs it seems to me that the plug may not have been threaded in all the way to begin with.

Thank You

 

[Keith_J]

The replacement plugs appear to have different sealing geometries. The threads do not seal, it is the shoulder which seals the combustion chamber. If they do not leak (soapy water around the threads on cold start), all is fine.

Wiring? The plugs are parallel, electrically.

 

[sloth646]

So I think I figured out what the what the my mystery wires are. What I think happened is their is a short in the original glow plug wire that connects to the fourth glow plug. Some military mechanic connected a new orange wire to the glow plug relay. Then added three green wires to the orange wire for testing purposes. I have three orange wires that connect to glow plug relay. Should only be two right? Or what I think I figured out could be completly wrong. Here are some pics.

 

[sloth646]

So I solved my glowplug issue. I called and talked to mechanic and he said that the proplem was there is carbon build up in the hole for the glowplug. What he told me to do was take vasiline and put it on the threads of the glow plug and thread it in and out. Now this took forever, But eventualy the glow plug started going in further and further. I would take the glow plug out clean the black off it and add some more vasiline every so often. Probably about an hour of in and out's. Hope this helps anyone that run's into this problem.

P.S.

Thank you everyone for your input.