Changing Glow Plugs on a CDI - PeachParts Mercedes-Benz Forum

BLACKCDI · #1 02-22-2009, 09:14 PM

I am about to put in an order for a 6 new GP for my 2005 CDI.
It has 103.000 with original plugs and the check engine light along with glow plug light are on. The car starts perfect but I would like to change them out, it's time anyway.
There are quite a bit of GP manufacturers out there, should I just stick with Bosh? I also have read several horror stories about broken GP, anyone had any problems like that with a 2005 CDI? Anything I should look out for?

KarTek · #2 02-22-2009, 09:21 PM

From what I've read, they have similar problems with breakage that the OM606's do. The advantage of the CDI is that there is a special tool for removing the broken ones.

TMAllison · #3 02-22-2009, 09:41 PM

Call your local dealer; OEM is probably Beru rather than Bosch.

BLACKCDI · #4 02-25-2009, 11:43 AM

Called a dealer yesterday, they quoted me $50 per plug

Anyway I have ordered 6 Bosh 0250202045 plugs from ******** for $16.75 each. Funny thing is that both Autozone and Pep Boys were out of stock indefinitely.
I have read somewhere that it is recommended to apply coper based anti seize compound to the body of the plug before install. Anyone has any good recommendations to something like this I can purchase at my local autozone or pep boys?

michakaveli · #5 02-25-2009, 12:03 PM

Subscribed.

TMAllison · #6 02-25-2009, 12:16 PM

Didnt realize you were local to me. WC MB is worthless. Did they at least tell you which manufacturer was OEM?

Beru sells a high temp grease tht they recommend for their plugs. MB doesn't use anything.

Diesel911 · #7 02-26-2009, 12:10 AM

Quote:

Originally Posted by BLACKCDI

Called a dealer yesterday, they quoted me $50 per plug

Anyway I have ordered 6 Bosh 0250202045 plugs from ******** for $16.75 each. Funny thing is that both Autozone and Pep Boys were out of stock indefinitely.
have read somewhere that it is recommended to apply coper based anti seize compound to the body of the plug before install. Anyone has any good recommendations to something like this I can purchase at my local autozone or pep boys?I

Beru makes a special grease. However, I have no idea where someone can get some.
http://www.beru.com/english/produkte/gluehkerzen/einbautipps.php

Never-Seez type compounds are available at the regular auto part stores and have stood the test of time.
They have both Copper and silver (nickel?) Never-Seez. I have only ever used the Silver type and have never had any problems on any Glow Plugs of any make or any other parts I have used it on.
I did read somewhere that for this use the Copper Never-Seeze is better but I was not convinced by their argument (in a one of the Threads somewhere).
Also these plugs get trapped by Carbon Deposits around the tip of the plug as well as sticking in the threaded area. Ream out or use an alternative method to clean out these deposits from the Glow Plug holes before new plugs go in.

compu_85 · #8 02-26-2009, 01:15 AM

Does your CDI use ceramic plugs? If so be *VERY* careful when you take them out. The tips break off very easily.

FYI, Bosch quit making the ceramic glow plugs for the 1.9 and 2.0 Volkswagen PD TDI engines. Current stocks have been exhausted, and a new steel tip plug is all that is available. The only problem is that the ceramic plugs ran at 7 volts, and the new steel tipped ones run at 5, so without a computer reflash the new plugs will burn out very quickly.

-Jason

BLACKCDI · #9 03-08-2009, 04:56 PM

Ok, so this morning I decided to tackle glow plugs on my CDI. Sprayed them with liquid wrench waited for an hour and started with the second glow plug from the front of the engine, just too see if it will budge.
No, way the glow plug seemed frozen, I did not force it and tried another one to my surprise it budged, I slowly started unbolting..it was creaking a bit so I went very slowly. Then tried another one, success, then another one and was able to unbolt and remove 5 glow plugs pretty easily!
Now the only one that's left is the first glow plug I tried unbolting, I applied considerable force to it with a small wrench, not even a slightest movement. BTW the glow plugs looked very clean without any carbon build up on them.
Funny thing is that the glow plug I am trying to unbolt is one glow plug that has been replaced by the dealer 40k miles ago! Bastards probably torqued it down!

So now what do you suggest I do:
1) Replace 5 glow plugs and forget about this one since it's probably still good.
2)Let it soak for a bit longer and try a bigger wrench?

GregoryV022 · #10 03-08-2009, 05:03 PM

soak it and wrench it. its going to have to come out anyway. might as well be now

babymog · #11 03-08-2009, 05:04 PM

I'd try replacing the rest of the GPs, soaking the offending one with PB Blaster during the service, then run the engine to warm (expanding the aluminum head & threads), try the GP again.

If possible try a little impact on the hex of the GP to see if it'll break any bonds.

You could even start with the block heater if you want, can't hurt.

Good luck!!

TMAllison · #12 03-08-2009, 06:27 PM

Heat engine to operating temp, then freeze the GP using spray made for that purpose and attempt to remove.

Another member did some failure analysis on Beru plugs for the 606. With teh body in a vise they typically sheared at 80-90NM. Ought to be safe to go up to 40-50nm trying to extract.

#13 03-08-2009, 06:44 PM

http://www.youtube.com/watch?v=koghDoROFko

BLACKCDI · #14 03-08-2009, 07:05 PM

I am so pissed

, drove the car with penetrant on the glow plug, came back put some more penetrant. The glow plug started to budge! It was creaking but coming out slowly. I was carefull not to apply alot of pressure on it. After 30 min it was almost all out I would say %70. And then it suddenly started turning easily, god damn it, it broke at the thread!
It's basically almost out, is there something I can use to grab the thread and keep unscrewing this damn plug? The glow system works perfect, not a one misfire, and the glow light operates perfect now

)))
It boggles my mind that over all these years glow plug manufacturers havent started using better grade steel for their glow plugs!

#15 03-08-2009, 07:11 PM

Its not from the grade of metals, its the dissimilar metals contacting. Thats why your GP started coming out easier when you got the engine hot, the aluminum head expanded more than the GP.