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tbeavers
05-18-2015, 17:46
I had one glow plug stuck and I worked and worked on it and finally got it out kinda the other half is sitting on my piston is there any way to get it out without pulling the head off

DmaxMaverick
05-19-2015, 00:33
Do you know it is, in fact, sitting on the piston? If it just broke off after tugging and twisting, chances are it's still in the GP hole, and you can retrieve it just by removing the injector. If it fell off, it may still be in the pre-cup. Pull the injector and have a look. If it's in there, plug the hole before it gets a chance to fall through the flash-hole. If it hasn't, it's a piece of cake. Go to the reply I did in your other thread (won't start), and pick up wherever you are in the process. If you skipped a step (such as not plugging the flash-hole) and it fell into the cylinder, then you can take a chance that it will blow out the exhaust valve. Otherwise, you'll have to pull the head.

tbeavers
05-19-2015, 07:15
I had pulled the injector and and grabed it with some vice grips and when I grabbed it it shattered in to a bunch of pices and fell down in there

Dvldog8793
05-19-2015, 07:31
Get as powerful shop vac as you can find. Make an adapter of some kind(read-duct tape) and try to suck out as many pieces as you can through the injector hole. You will need to keep the glow plug hole open for this to work.

FYI- When in the Marines we had allot of problems with glow plugs swelling. The common thought(not mine) was to take out the ones that came out. The ones that broke and couldn't be easily removed, pieces were left in and the engine started. I would estimate that about 70-80% of the engines survived. All of them made a hell-of-a racket when fired up:eek:
The engines that didn't survive were sent up to next level of repair. Tax dollars at work! :mad: At least in my shop while I was in charge, that procedure stopped.

IMHO- Work on the rest of glow plugs. If more experience the same issue, then your chance of engine survival is going down with each one. Also, the cost and time to pull the head is less than the cost and time of a damaged piston....but if neither is an option then your decision is already made;)

Good luck!

DmaxMaverick
05-19-2015, 10:07
A shop vac won't pull any pieces from the cylinder unless you have extremely good luck. IF the piston is near the top, and IF a valve is open, it might pull the pieces from the cylinder (no guarantees). If these rare conditions exist, plug the GP hole with the old/broken plug, so all the suction comes through the open valve and through the flash-hole. If both valves are closed, and/or the piston is near the bottom, no chance of pulling any pieces from the cylinder. It must have some level of flow to move those little, dense pieces (the rings won't pass enough air to make one bit of difference). Gravity is your friend, as the flash-hole is low, placing the pieces near it, making the air turbulence likely to pick them up and carry them out. Of course, you can remove the valve cover and visually confirm an open valve, or manually depress a valve. It depends on how far you want to go before flipping the coin and measuring the risk factors.

The "crumbled" pieces shouldn't be metal, but the powdery ceramic insulator material (not solid like a spark plug). If large pieces didn't fall in, they won't cause any immediate damage (such as piston interference), and will quickly pass out of the cylinder. The ceramic insulator material is abrasive, so there is that risk. The GP casing metal is soft and won't cause any damage, as long as it isn't filled with the insulator material. Whatever is left of the center conductor wire is of no consequence. If you can rotate the crank a few times by hand (wrench), it won't cause issues on start-up. If you start it without incident, just drive and don't look back. Odds are, the pieces will remain low on the piston and inside the Ricardo Bowl, so chance of actual interference is less than it could be. If anything bad does happen, it will be long before the engine warms up, within only a few combustion cycles. I've done this many times and haven't yet killed an engine. This is not to say it can't happen.

joeq
05-19-2015, 16:09
Wow, great discussion for a diesel newb like me. I hadn't even given this a thought, when I was removing my stuck glows plugs to do a compression test. I was lucky, they all came out. It was strange, because a week before, when I tried most wouldn't come out, even by yanking. But a week later, they all slid right out, but one needed a little persuading.