If I Break a Glow Plug...

LMJ

Veteran Member
Joined
Feb 22, 2010
Location
Virginia
TDI
2000 VW Golf
Getting the glow plug code 2.5 years after the harness was replaced. I'm assuming it's the one stubborn plug that I wasn't able to remove. Gonna give it another shot after soaking it in with penatrating oil. If the plug breaks while I'm trying to remove it, am I screwed. What would be the procedure for removing it then.
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
I suggest a tee handle wrench. It helps you apply only torque with no bending on the plug.

If you don't have a tee use an extension so you can brace the head of the wrench with one hand while applying torque with the other.

Some guys suggest a torque wrench to keep from applying too much and twisting it off. I don't recall the max torque.
 

csstevej

Top Post Dawg
Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
I believe it’s 15 lbs.
If you do break the GP off it will be difficult to get it out, I’ve not been successful at it. I even snapped the extractor out too.
In my case the GP didn’t even budge, it snapped flush and didn’t leak.
It stayed that way for damn near 13 years till I just changed out my head ( snapped at Approx 120,xxx miles till about 394,xxx miles).

To keep the engine check light off ,depending on if you have a 2 wire or 4 wire GP system, connect all leads together, either by cutting and twisting or soldering.
This way the engine ECU doesn’t see an imbalance in current and doesn’t set an ECL.

Otherwise you need to pull the head and have a machine shop remove it.

Starting when extremely cold will be rough for the first 10 seconds but will smooth out.
Or install a frost heater as I did and keep on trucking.

When I did pull the head at 394, xxx miles even the cylinder with the broken GP still looked like the other 3 cylinders and still had the original crosshatch marks from original build.
 

ghohouston

Veteran Member
Joined
Apr 2, 2013
Location
Lewisville, Texas
TDI
2001 Jetta Sedan TDI 5 Speed
Get the engine good and hot before trying to remove, and you need a quick burst of energy to "break" it free, not slow torque.
 

STDOUBT

Veteran Member
Joined
Jul 30, 2007
Location
Portland, effing Oregon
TDI
dos jettas
I recommend Kroil. Time -honored penetrant. A few drops each plug when hot, let cool, drop some more....repeat.
I think I alternated a few time with carb cleaner too.
Also, I recommend an actual torque wrench like pictured below. DO not exceed 25nm reversing them out.

I was so paranoid removing a couple stuck plugs, but I just took my time, and actually gave it about 2 weeks working them in-and-out, back-and-forth...over time and with repeated (but conservative) use of penetrant they'll come loose. Also see:
https://forums.tdiclub.com/showthread.php?t=79819
All due respect ghohouston, I didn't need a quick burst, and would not recommend that. Slow torque worked in my case. But like I said, I was really paranoid.


Sturtevant Richmont MD70Nm Dial Torque wrench

 
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Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
I'm sorry, but I think some of the information above is not exactly correct.

First, I suggest 'choosing your battles'. If this is not a fight you have to do, DON'T. After all, it's getting to the point a glow plug (gp) isn't needed until next winter.

If you get it to loosen, but are unable to remove it, and THEN break it off, with the plug off it's seat, you will be removing your cylinder head. We have drilled out hundreds of glow plugs. We are good at it, but I would rather never do the next one.

Here are the ground rules for the best way to remove a stuck glow plug:

First, get a very accurate torque wrench and make sure exactly where 30 ft lbs of torque is. We have a simple and accurate method for properly setting a torque wrench.
A clic-stop torque wrench is perfect. The point is, when the torque applied on a glow plug is 33 ft lbs, that is all the thin wall between the 10mm nut on the g.p. and the body of the plug can take. Any torque above 33 ft lbs and you can expect the nut to shear and then, all it will do is spin in place. So, methods like a Tee handle or a 'Burst of energy'... how you going to guess at 30 ft lb 'burst'? However, I will agree, attempts with the engine hot will promote removal, as the aluminum of the head will expand more than the gp when heated.

If the gp will not budge, and the nut shears, the only choice then is to break off the nut and with the cylinder head on the bench, drill it out. More on the drill-out to follow...

As long as the gp is intact, we suggest a very good penetrating oil and to build a clay dike in front and around the gp so each time you come to a stop for the day, you can pour a 1/2 teaspoon of penetrant around the gp and let it work it's way into the threads. We may do this for a week before actually attempting the put torque on the gp.

One of the rules is, if the torque wrench clics at 30 ft lbs, STOP! Go the OTHER WAY! It doesn't matter if you loosen or tighten the gp, just get it to move. Once I am able to get it to move even the slightest amount, I can get it out, but don't pass 30 ft lbs torque. It may only move 1/4 turn and stop. Retighten it and loosen, tighten, loosen... eventually, it will move a bit more. I'd rather spend 45 minutes taking out a gp, than 90 minutes drilling one out with the cylinder head on the bench.

If you are able to remove the gp, it's not 'all done'. You need to check the threads on the gp and the threads in the hole. If you gp is damaged or stripped, so also are your threads in the bore. We use a 10 x 1.0 tap and a tap Tee handle with a 1/4" x 6" ratchet extension in it. Turn the extension 'backward' to how you would normally use it, with the square of the tap going into the female end of the extension and the male end going into the Tee handle. This will help you get far enough away from the head that you can spin the handle without hitting the cylinder head. You may find it helpful to use an arbor whose I.D matches the diameter of the tap and rest the arbor on the shoulder around the gp hole. That surface is square to the gp hole. Gently, by hand, turn the tap into the hole, attempting to follow the original gp threads.

The most common stripped gp hole is the #3. The reason is that the vacuum ball gets in the way of a straight shot at the gp threads. Remove the two bolts or bend the bracket holding the vacuum ball and get it out of the way when removing or installing gp's.

If the gp hole either has stripped out threads or damaged and pulled threads, we recommend using our Glow Plug Recoil Repair Kit. Although some feel the TimeSert are a better insert, the Recoil repair is simpler and cheaper. Also, in the event the Recoil does not work, you can still use the TimeSert as a 'second attempt'. We have LOTS of recoils installed and almost zero failures over at least 10 years. We have proven this methods effectiveness.

It may be the threads are good, but you may see is a bunch of carbon packed up into the threads of the gp or the gp hole. This is caused by inappropriate seating of the gp contact bevel to the seat inside of the cylinder head. If the carbon built up on the seat is not removed, the gp will seat on the CARBON instead of the aluminum of the head. This will cause the gp to leak slightly and carbon from the combustion chamber will force it's way into the threads, making a very hard to remove gp. The angle of the seat, if I remember correctly, is about 50 degrees. We make a gp seat cutter designed to quickly and safely remove the carbon and recut the gp cylinder seat for the proper contact surface and angle. Some have used an old gp and ground the threads off of the body so it will spin in the bore, then cut a small slice into the seat bevel on the gp. This can also remove the carbon. If you can't see a clean circle of aluminum at the bottom of the gp, you cannot expect the gp to seat without leaking.

Now, if the glow plug breaks off, you have few choices. The most important thing to know is the gp is at a COMPOUND ANGLE. It not only tilts away from the head at a 60 degree angle, but also 15 degrees to the side. There are many ruined heads that the drill went through the side of the gp into the water jacket, ruining the head. We use a drill in the gp hole to find the proper angle to drill. For example, if #3 gp needs drilled out, we put a 17/64" (I believe that is the best fit..) into the #4 gp hole, then tilt the drill to match the angle for drilling out #3. Methods...1) Use hand drill and gradually increase the hole size, making sure you do not drill down to the gp seat. Finish with a left hand drill bit, which will spin the shell of threads out of the hole. 2) There are machine shops that can remove the gp with an EDM machine, which basically, burns the gp out of the head with an electrical discharge. Figure $100-$150. Or, you can send it to me... I usually get them out for $90.

Another common mistake is expecting an easy-out to remove the gp. What we end up getting is a gp with an easy-out broken off in the hole, which compounds the effort to remove it. DO NOT use an easy out. I have NEVER seen it work.
 
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LMJ

Veteran Member
Joined
Feb 22, 2010
Location
Virginia
TDI
2000 VW Golf
Hey, thanks for all the information. I have until the end of september to get it done. I'll propbably change the other plugs and check wiring before attempting to remove the stubborn one.
 

Franko6

Vendor , w/Business number
Joined
May 7, 2005
Location
Sw Missouri
TDI
Jetta, 99, Silver`
LMJ,

You got lots of time. No rush. Just don't wait till the last minute to figure out if the gp is stuck for good or not.

One thing I did not mention, in areas that use lots of road salt, there is a problem with both the injectors and the glow plugs. The steel of the injector and gp's against the aluminum of the cylinders, mixed with salt, creates aluminum oxide. That is great for sand paper, but not very good for threads or injector holes. It is a white, powdery and very hard abrasive. To keep it out of gp's use preparations like Permatex anti-seize. We prefer a paste used on aluminum wiring, available at most HVAC suppliers. It is a Nickel based grease, we use on everything from ground wires to wheel nuts and of course, gp's. A very small dab is all it takes.
 

tdiDerry

Veteran Member
Joined
Oct 18, 2009
Location
Chandler, AZ USA
TDI
2006 Jetta MkV Sedan; 2002 Jetta MkIV Sedan; 1999 Jetta MkIV Sedan
--Trust Frank06..

I did this a few year ago (broke #4 gp off) amd he had me call him. We spent a good 30 mins on a call. He is awesome. I was able to drill it out and made my own extractor. Look for threads by my name..

--Also if your worried about cold winter starts and cant get the gp out just install a 'frostheater' cost you $150 And 2 hours..

Good luck
 

lpasquale

Active member
Joined
Feb 7, 2008
Location
Hookstown, PA
TDI
2003 Jetta GLS ALH 01M - 325k and going strong - Sort of...
Csstevej,
Can you please elaborate on the wiring scheme to keep the car from triggering the cel. I have a new 4 wire gp harness I’m about to install in an 03 alh car and I’d like to perform the wire mod before the harness install. Thanks in advance....
 

csstevej

Top Post Dawg
Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
The only reason I did the mod as I had broken the glow plug flush with the head.

So I only had three plugs connected in a 2 wire system ( I have an 01).
2 GP’s were connected to one wire and the other 2 Gp’s to the other wire.

Since there was only 3 GP’s it created a current imbalance which triggered the light.

To stop the light all’s I did was strip some of the 2 wire harness and soldered them together so as not to cause a light because now there is no load imbalance.

On a 4 wire system you would do the same thing, strip back some wire on all 4 wires and solder them together.

The only real difference between the 2 and 4 wire is on a 2 wire system when you get an CEL you have to physically check each GP to see which on is bad.
On a 4 wire system when you get a CEL it will tell you which plug is bad.
 

Rrusse11

Veteran Member
Joined
Jan 23, 2014
Location
PA Deutsch Country
TDI
2002 Golf, 5spd; 05 Jeep CRD
@Franko6,
Is this the stuff you're using?


https://www.zoro.com/jet-lube-anti-seize-compound-pure-nickel-4-oz-13655/i/G3640262/
 

jackbombay

Top Post Dawg
Joined
Mar 12, 2002
Location
Diesel knows best
TDI
A4 Jetta
Get it on the highway, warm it right up
This! Cover the radiator too!


Get the engine good and hot before trying to remove, and you need a quick burst of energy to "break" it free, not slow torque.
The older sprinter 5 cylinder engines are notorious for the GPs getting stuck in the head. A guy that has rebuilt a bunch of them says he has never had an issue removing the glow plugs with an impact driver, he of course is in a situation where a broken glow plug is not a big deal as the head is coming off anyway, but it certainly backs up the "quick burst to break it free" idea. I'm not necessarily condoning impact driver use, but it is some food for thought.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
I've read about using max torque as a technique for removing fasteners. Maybe that works on the bench, but in my experience impact is the only way, not necessarily power assisted. Quality 6 point socket, full depth, torque meticulously applied at 90 degrees. Temperature manipulation can also help, especially since the steel glow plug is threaded into an aluminum head.
 

LMJ

Veteran Member
Joined
Feb 22, 2010
Location
Virginia
TDI
2000 VW Golf
Mission accomplished. Just removed the "first" plug closest to the wires and replaced with a used one that I surprisingly had. Ordered full set to replace soon. Dash light stays off so I can get it inspected next month.
 
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