glow plug removal problem

[bourne]

Hi ther folks,
I was wondering if anyone out there in mercland may have some advice to remove the glowplugs from my '98 E300T as I suspect I now have 2 that have failed. I took it to my local non specialist garage and he couldn't get them out without the risk of snapping them off in the head! Does any body have any tips????

thanks for your help,

best regards, Bill.

 

[simon_wall69]

It is a very difficult job and could well result in you having to remove the head to do it.

Only hints could be make sure that the engine is warm and use lots of penetrating oil but then there is still a good chance of snapping. I had (or at least Merx had) huge problems removing mine and couldn't do it in the end; it did always start (but very badly) even though it had only 1 working glow plug left.

Even when drilled mine wouldn't come out!

Apparently, some people do use liquid nitrogen to shrink the glow plug, but I can't imagine that this is a realistic option unless you work in a science lab somewhere.

 

[Number_Cruncher]

Beru quote a failure torque of 45Nm for these plugs, but, tests have shown that you can go to about 80 before they finally snap. I found the stubborn ones in my '95 E300D 'gave' at about 60Nm.

The vital thing when re-installing is to make sure the taper seats fully, preventing carbon getting past the taper seal. So, cleanliness, and proper tightening is important.

 

[simon_wall69]

All of mine bar one snapped in the head. Although it had done a shedload of miles (over 400,000!)

 

[bassbluestew]

I also have a 300TD W210 and replaced all 6 glow plugs fairly recently. They all came out extremely easily and when I mentioned to the local mechanic that I was worried after reading some horror stories on here, he was genuinely surprised. Maybe as my car, though ten years old had done only 90k miles this made the removal easier.

Sorry to be hearing of more horror stories and good luck getting them sorted.

S

 

[BannyDoy]

I recently bought my 98 E300TD and fell for the oldest trick in the book (the dude had already started it and got it warmed up)... I would not have thought that changing the glow plugs would be such a big deal.
The next day after buying the car I started it up and low and behold it was lumpy and smokey, doesn't take long to heat up and run smoothly but that's not the point.
So finally I got round to buying some Bosch Duraterm (£55 for the six), I wanted the new Chromium ones, but could seem to find any for a reasonable price (aparently they don't rust). Anyway, I enlisted the help of my friend a mechanic... popped the hood and discovered that one glow plug has already been broken off and butchered, as Bill and Ted would say, "Knarly Dude!"
So far two others are stuck.
So bassbluestew you are a jammy dodger!
I've just spent an hour or so researching on the net in general stories about the removal of these sort of broken of studs and plugs and things and it was painful! Possibly not as painful as reading this dribble.
It looks as though the previous bodgers decided to abandon ship having drilled it out and tapped a new thread... and failing to extract it using a helicoil or ezyout or somesuch thing! this does not bode well and clearly it's not going to go easy on us.
Still we shall battle on and let you know any useful news.

For anyone out there fitting new glowplugs... please, for the sake of the next poor sucker to own the car, "put some anti-seize stuff on the threads!"

 

[rpe2]

Get the engine really hot then remove (more difficult on a TD engine I know).

 

[tonyb]

Hiya all...member.. parrot of doom...has posted a comment on this prob and i have to say what he says is the best advice...dont rush it (days rather than hours or mins..lots of pen oil..wd40 etc...i done mine this week 2 outta the six were dead, lots of smoke and keeping fingers on starter to get it to run.....luckily all mine came out eventually..but 2 were a real bugger! also i had to get a new inlet manifold gasket (fell apart)and rubber hose (perished) so i would get these before starting this job... I got the new glowplugs from europarts DENSO DG-106 total price for 6...£59.43..(starts great now and no smoke) E300D 1996 ..86300 miles (rustbucket)..good luck to all who do this job...

 

[BannyDoy]

Well, I don't know how you're getting on with your stuck glow plugs Bourne... but I think I'm getting to a point where I have to decide if taking the head off to get the the one butchered and broken plug out is going to be more hassle than it's worth...
Slow and steady is good advice with patience and penertrative oil in equal amounts. The ones that finally came out show clear evidence of not being done up properly in the first place, as carbon had escaped past the tapered thread and obviously caused a problem and I suppose loss of compression.
The broken one has been drilled further and had a straight thread bar inserted, but I felt the shaft sticking out was too long and showed evidence that it would twist midway and snap.
So it will be shortened to get the force nearer to the plug. I read somewhere that the left hand threaded extraction thingamabobs aren't always the best choice as the force is used in winding themselves 'in' rather than forcing the broken plug round... (if you get the picture), which is probably going to help expand the stuck plug in the hole even more... then snap, so I opted for the straight thread bar. But Lordy is that puppy stuck fast!
Of course it had to be the plug nearest the cab/bulkhead, so had to remove the oil filter housing and various pipes and stuff.
The bits we've removed are growing all the time in order to get at the darn thing.
Sorry Bourne, I'm moaning on your thread.
But maybe it will help someone somewhere...

Is anyone out there living on 5 glow plugs instead of 6...?

 

[kebo57]

The broken one has been drilled further and had a straight thread bar inserted, but I felt the shaft sticking out was too long and showed evidence that it would twist midway and snap.
So it will be shortened to get the force nearer to the plug.

Hi has the broken one been taped out to accept the thread of the straight thread bar if so then a long length ofbar could be made in to a slide hamer arangement

I read somewhere that the left hand threaded extraction thingamabobs aren't always the best choice as the force is used in winding themselves 'in' rather than forcing the broken plug round... (if you get the picture), which is probably going to help expand the stuck plug in the hole even more... then snap,

I agree with the above & am very interest in this extraction & would appreciate a picture of a removed plug & the location of the broken plug as I only have experience with the ML 270 engine

Thanks Kevin

 

[BannyDoy]

Hi, I see where you are coming from with the slide hammer arrangement... it might well be worth a punt! I think I'd try anything to avoid disturbing the head at this point.

As far as seeing a picture goes... sure I'll make some and post, but in the meantime the darn thing is still stuck inside. We are being careful not to rush things as breaking a tool off in the plug at this point is the last thing we want.

 

[Frontstep]

Bit late too reply, but had problem removing glow plug, in the end 1,Get engine hot, 2,lot's of penetrating oil 3,cooled plug with freezer spray in this case for removing chewing gum but I think they (freezer sprays) are same stuff 4, Then and perhaps the most usefull tighten first then undo slowly always going back to tight position before loosening more liberal penetrating oil often.

 

[clarkoid]

Running on 5 glow plugs not 6!

Hi I own a e300td 98 reg currently running on at most 5 glow plugs and seem to have the normall problem on start up very very limpy engine and lots of smoke,,,Not quite the Mercedes Benz look,,, Mecanic is gonna try and fit new one's tomorow ... What does yours run like?

Clarkoid

 

[emlclcy]

Hi ther folks,
I was wondering if anyone out there in mercland may have some advice to remove the glowplugs from my '98 E300T as I suspect I now have 2 that have failed. I took it to my local non specialist garage and he couldn't get them out without the risk of snapping them off in the head! Does any body have any tips????

thanks for your help,

best regards, Bill.

How about using an 'air wrench' set on a low torque, lots of short pulses sort of thing

 

[exeng]

you can remove broken plugs on this model without removing the head i have done double figures its tricky but possible a lot depends on how they break

 

[Rory]

How about using an 'air wrench' set on a low torque, lots of short pulses sort of thing

I've seen specialist air tools mentioned for this job but no idea if they're any good or not. One was mentioned at £1000.

ETA: Quick Google finds this: http://www.toolboxking.com/product_info.php?products_id=7863&osCsid=06eedcb76b8f8e4d4448cd296695501c

 

[exeng]

I have the pneumatic system for removing glow plugs and i wish it only cost £1000 it is the best tool for the removing glow plugs but the manufacturer will tell you it works best on the 10m/m and 8 m/m plugs i think yours will have the 12m/m.
As i stated you can still get them out when they snap if you are careful and if they snap the usual way

 

[dannyt]

Hi has the broken one been taped out to accept the thread of the straight thread bar if so then a long length ofbar could be made in to a slide hamer arangement

I agree with the above & am very interest in this extraction & would appreciate a picture of a removed plug & the location of the broken plug as I only have experience with the ML 270 engine

Thanks Kevin

i have a ml ml 2.7 x reg glow plugs 3,4 playing up i c u have experience on this engine do u have any tips apart from hot engine and lube is a slide hammer affective guna start it 2moz after work so quick response wud b nice as merc want £260 to change 2 plugs and thats if they dont grt stuck as there esy to get to on this car **** take

 

[Cole@MBS]

Just get the engine as hot as poss, loads of lube and slowly when trying to remove........

 

[Alex M Grieve]

Just get the engine as hot as poss, loads of lube and slowly when trying to remove........

I bet you are famous for your slide hammer too Colin!