No wonder I've had lumpy starting

[greasemonkey]

If you get to the point where you think the head is going to have to come off, then its worth drilling it out, and blasting some air in through the injector hole, to get the swarf out. Have a wiggle round with a magnet aswell. Nothing to loose.

[Rotary-Motion]

Is there anything that will dissolve carbon? an oven type cleaner maybe, pour some in the hole, leave, then run the engine?

carburetor cleaner is the stuff.

[Rotary-Motion]

If you get to the point where you think the head is going to have to come off, then its worth drilling it out, and blasting some air in through the injector hole, to get the swarf out. Have a wiggle round with a magnet aswell. Nothing to loose.

what i would do

[McDuff]

Araldite will not take the torque required and you also run the risk of any excess getting over the thread in the head - is the tip magnetic - if so use an extractor, if it falls into chamber use an extending magnet to draw it out through the injector opening

[nigelb]

If you get to the point where you think the head is going to have to come off, then its worth drilling it out, and blasting some air in through the injector hole, to get the swarf out. Have a wiggle round with a magnet aswell. Nothing to loose.

That's a good point well made Andrew

[greasemonkey]

Aldi had an bore camera on sale a while back, for £60. Dunno if they have them now, but it would not be big money to be able to have a peep around in the bore, after the job was done. Another thing you could do, is make up a tube to go on the end of a hoover, and suck the swarf out. just make sure anything that goes in is plenty small enough to come out, but the injector hole is a fair size, so shouldn't be a problem.

[nigelb]

I have access to that type of camera from work. We use them to check oil ways for swarf and drill witness's

[Glycer-rides]

Is there anything that will dissolve carbon? an oven type cleaner maybe, pour some in the hole, leave, then run the engine?

Oven cleaner's not good on aluminium.
I'd still try getting a tap of the optimum size just to 'catch' enough on the inner bore of the plug tip to allow it to be pulled out.
Chopping an old one up would take a few mins. I can't remember what's in there...element, powder?

[Head Womble]

Nige if you use something to eat the carbon so it frees off the end of the plug and then run the engine I don't think it will get sucked into the chamber,
the combustion pressure is far greater than the comparatively low negative pressure you'll get on the intake stroke.

Is it a DI or IDI, would the tip be able to make it out of the pre-chamber if it's an IDI engine ?

[nigelb]

The centre material is a white substance....maybe some sort of ceramic.

The engine is the AGP non turbo 1.9SDI

[nigelb]

Nige if you use something to eat the carbon so it frees off the end of the plug and then run the engine I don't think it will get sucked into the chamber,
the combustion pressure is far greater than the comparatively low negative pressure you'll get on the intake stroke.

I think the risk is just to great on that. The point of release could never be gauged or judged. If it was on a downward stroke the damage coming up could be catastrophic

[Head Womble]

Nige if you use something to eat the carbon so it frees off the end of the plug and then run the engine I don't think it will get sucked into the chamber,
the combustion pressure is far greater than the comparatively low negative pressure you'll get on the intake stroke.

I think the risk is just to great on that. The point of release could never be gauged or judged. If it was on a downward stroke the damage coming up could be catastrophic

Fare point, it's easy for us to come up with ideas but it's your engine and your risk.

[nigelb]

The ideas and discussion regarding my problem has been terrific. I am grateful for all the input. I'm taking the remaining plugs into work tomorrow to see if there is a suitably long drill and tap set in which to borrow. We'll see what happens from there.

Rest assured that a positive outcome will result from this and I'll post the results in due course. There is no point asking questions if they are not acted upon. Thanks guys.
 

[Glycer-rides]

In the meantime, leave some penetrant in there to soak? Maybe wick it up with a rag and change it every day.

Then you could disconnect the IP fuel shut off solenoid, so it won't fire up, and try to blow it out again by cranking the engine.

[nigelb]

I've been giving this problem lots of thought today and the centre of the stuck section will be easily drillable using a dremel type set up. I've now got the injector out and it affords me plenty of room in which to work. I could do with getting a small diameter "easy out" to assist in the extration. Still got a few days in which to source something. The internal diameter of the the broken piece, when the white ceramic insulator has been removed is 4mm. So plenty of material to have a go at as the OD is 5mm

It looks as though the glow part is possibly "welded" to the bore. The plug which came out is very clean and under a magnifyer there appears to some evidence of arc-ing from the centre electrode.

I've now done as suggested and filled the bore with some AC90.

I wont be able to get on and do the job properly until the weekend. I dont get back from work til 5.30 and don't relish working in the dark.

If anybody else has any bright ideas different to what has already been discussed....please....shout up!