7.3 IDI Glowplug srewed up after removal

[derjackistweg]

I - probably - got an issue with the glow plug at #1 cylinder.

Vehicle:
E350 Van 1993
Engine 7.3 IDI N/A 100k miles

As the engine did not start in cold weather recently (just purchased) at 40F, I decided to change the glowplugs.
I removed the Glowplug at cylinder #1 and all worked fine. Glowplug was removed in one pice- BUT I cannot srew in the new one! The hole is just about 10mm deep until there is something that stops it.

I have no idea what this means. Looks like something from the inside has blocked the hole. What can I do?

 

[OLDBULL8]

Was the GP you took out in one piece or was the tip broke off? Gotta know that before answering.

 

[OLDBULL8]

Re-read your post. It did come out in one piece. That is a ZD9 GP your putting back in? IF the old came out like that, surely the new should go in. There can't be anything in the hole to stop it. the threads are 10.01 mm. Did you try and stick something else in the hole? You should put some antisieze on the new ones.

 

[derjackistweg]

OLDBULL8 is correct. The old Glowplug came out in one piece without a physical damage on the outside. Probably it is a worn out GP. The GP are from Delphi and the other all fit great. This should not be the issue.

At first I was not sure if I tried the correct hole, because I cannot see anything (it´s a VAN). But after making photos like this I am sadly sure it is the correct spot. I can see a thread if I am correct. On the first photo you can see how deep the GP falls into the hole, before it is blocked by anything. I tried carefully with a screwdriver also, same result.

You must be registered for see images attach

I was wondering is - hopefully not- the pre-chamber inside the cylinder maybe has fallen out? and now blocked the hole after the old GP has come out. This would be a kind of disaster!

Here are some pictures so you can see how it looks (just temporary:
http://www.derjackistweg.de/glowplug/

 

[ToughOldFord]

It would be impossible for the pre-chamber to fall out. Even if it was loose in the head half of it rests on the engine block.

Are you certain that is a GP hole? As rusty as it is in that pic it looks like part of the exhaust. Better picture maybe?

 

[derjackistweg]

It would be impossible for the pre-chamber to fall out. Even if it was loose in the head half of it rests on the engine block.

Are you certain that is a GP hole? As rusty as it is in that pic it looks like part of the exhaust. Better picture maybe?

I know the pre-chamber cannot "fall out" - but maybe turn? This is the probably most rare possibility and the worst also.

Check out the link on my homepage derjackistweg. I just uploaded several pictures. My guess is also that the GP hole is a different one- but it´s really hard so see/figure out.

 

[ToughOldFord]

Even if it managed to turn the top side is circular and bowl shaped, the dimension is all the same and wouldn't interfere with the GP.

 

[derjackistweg]

If anyone could provide a picture of a 7.3 IDI´s #1 GP this would be great! So I could compare and see if this hole is really the wrong one (what would be great). The GP are, I guess, all in a row from #8-1 and in theory below the GP wire but with all the wires/hardlines etc. it is tricky to see if this area (with the hole) is correct. I guess so as the injector sits above.

 

[icanfixall]

That definitely is the glow plug hole. Its directly inline with the injecter. Only reason you can't get the new plug in is there is carbon build up around the hole. Try reinstalling the plug you took out. Then compare them closely to see whats differant.

 

[derjackistweg]

The old GP look the same as the new ones. The is no visible difference when laying next to each other. And the other ones all assembled fine. The GP hole is only ~ half an inch deep (10mm). The first picture above shows how "deep" the GP falls into the GP hole.

If I try to push, nothing happens. Although I tried this carefully! also with a small screwdriver.

 

[franklin2]

He has a good point in post #9. Put the old glowplug back in. Does it go all the way in? If it does, and the new one doesn't, you will have to put them side by side and stare at them till you figure out the difference. Either shorter, longer, different diameter, something.

 

[icanfixall]

That glow plug you removed probably had some carbon buildup on it thats now stuck in the bore of the head. Look closely at the new plug. See that bevel area under the threads between the end that sticks into the precup. Thats the seat. In the head there is another machined seat where this comes in contact to create a seal. Feel down into the hole for it. Once thats found tap the blunt punch or screwdriver into the middle of the hole to push whats plugging the hole. Whats in there will fall into the precup and be blown out the exhaust with no damage. If what you say about the plug came out complete then nothing else can be causing this stoppage. See if the old plug will fit back in the hole too and repost back. If it does then the new plug is larger diameter than the old one and cleaning out the hole is needed.

 

[derjackistweg]

That glow plug you removed probably had some carbon buildup on it thats now stuck in the bore of the head. Look closely at the new plug. See that bevel area under the threads between the end that sticks into the precup. Thats the seat. In the head there is another machined seat where this comes in contact to create a seal. Feel down into the hole for it. Once thats found tap the blunt punch or screwdriver into the middle of the hole to push whats plugging the hole. Whats in there will fall into the precup and be blown out the exhaust with no damage. If what you say about the plug came out complete then nothing else can be causing this stoppage. See if the old plug will fit back in the hole too and repost back. If it does then the new plug is larger diameter than the old one and cleaning out the hole is needed.

If I got you right- this might be the reason.
http://www.derjackistweg.de/wp-content/gallery/glowplug/dsc00017.jpg This Picture in full resolution looks like there is carbon all around that little hole that was left from the "hot" (1inch long smaller) part of the GP.
So if I do/did not put the GP in exact the correct angle inside, it would stop at that carbon. Could be the reason. I will check this, maybe today, it´s 9PM here right now.

 

[gdhillon]

maybe try cleaning the threads with a .22 gauge brass brush?.....I used a 12 gauge brush to clean the injector bores (as per fellow idi'ers instruction)

 

[derjackistweg]

So no short term solution in advance!

I tried to scratch with a 2mm (10th of an inch) flat screwdriver inside the hole. The screwdriver can be put inside the GP hole as deep as the original(same size)/new GP: ~15-20mm (almost an inch) or less. So no "hole inside a carbon `plug`" or something like this.

BUT I can at the side of the hole push the screwdriver with the flat part (less than 1mm) deeper! Seems like as deep as the GP will sit if correctly working. With hard trying I can turn the screwdriver, which means turning from the flat part to the 2mm wide and around. So there is definitely something preventing the GP hole to work like it should or in other words: blocking.