Glow plug replacement questions

b1mmuo27

New member
Doktor A-Where are you located? Do you work for Daimler? I used a 1/4" ratchet to remove or shear the glow plugs. From the top of the hex nut down body of the glow plug is one piece as you can see on the new champion plug. The electrode is sticking out from the bottom of that. From there up, it's an insert for the electrode. I would say the plug is made in 3 pieces. I challenge your remark regarding "easily" removed with a 3/8" wrench. Shall I do a video with a torque wrench to prove you wrong? Shall we use the rating 115 lbs-in the talkinghorse43 is quoting. There is no corrosion on the plugs. Here is a picture of the engine. I keep it pretty clean. Did you know that the fuel injection pressure is uped when the vehicles are brought into Canada? That the way they could meet the emission standards. When I picked up my Sprinter from the dealership new, both head lights didn't work. Straight from the factory the dealership claimed. Could a robot have over torqued the glow plugs?:thinking:DSCF0559.jpg

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b1mmuo27

New member
Doktor A- Altered Sprinter remarked the manual he is going by suggests the 48K for removing & inspecting the glow plugs. I agree when they are a problem like I have pull them out. I don't think they should be replaced as they are fried. Rather as a set, whether at 55K or 155K. I'm just glad we have forums to whine & complain about & find information too.:thumbup:
 

abittenbinder

Doktor A (864-623-9110)
The hex head is not "brazed or soldered"- the body is one machined piece. Our group member with the broken plug problem claims almost no torque when his sheared.

If you have the cylinder head at operating temp and use a short length 3/8 drive wrench, you likely won't have problems. I have loosened glow plugs with much more break-away torque than the actual specified tightening torque without failure. Doktor A
Where in the above quote did I say "easily"? There's nothing "easy" about this procedure. The access is horrific, your heart is pounding as you apply torque to each glow plug waiting for a "snap"-which thankfully, usually, doesn't come.

As I said-most owners likely won't have removal problems-I'm sorry to hear you did. From what you initially described, your glow plug sheared with little or no torque-that's unusual.

I don't want to see group members overly paranoid about some arbitrarily chosen replacement interval. Doktor A
 

b1mmuo27

New member
Where in the above quote did I say "easily"? There's nothing "easy" about this procedure. The access is horrific, your heart is pounding as you apply torque to each glow plug waiting for a "snap"-which thankfully, usually, doesn't come.

As I said-most owners likely won't have removal problems-I'm sorry to hear you did. From what you initially described, your glow plug sheared with little or no torque-that's unusual.

I don't want to see group members overly paranoid about some arbitrarily chosen replacement interval. Doktor A
Two blown headlights from the factory that's unusual too. Paying the dealership PDI fee's when the vehical was new, that's criminal as they shoudaaa caught this. Just proves PDI is just a money grab.
Normal operating temperature could be a wide ranging scale. In -15C temperatures the block could be warm to touch. In 30C temperatures the block could too hot to touch. A 30Km hike at highway speeds of 120K should & does bring the engine up to operating temperature but it's still cold. Woodaaa, shuodaaa, couldaaa doesn't exist in my world. What could go wrong, does. If you said it was easy mine would be hard. Serpentine belt replacement on this van was easy. Brake pad replacement was easy. Getting a North American alarm to work on this was hard. I did but I had to make my own switch to make it work. Glow plug replacement should be too. Access is wide open. Going in knowing what I do now may have changed the way I did it. I still have 1 more plug sheared off but i still have 3 that I haven't touched yet. Still pondering the action to be taken. :thinking:
 

talkinghorse43

Active member
The hex head is not "brazed or soldered"- the body is one machined piece.Doktor A
The last pic in that group showing a side view of the sheared-off nut looks so much like a tubing fitting nut. If you're familiar with them, like nuts from the tubing fitting brands Swagelok or Tylok. Seems strange to me the nut would shear at a plane displaced from the plane of the edge of the hex faces unless there was a plane of weakness there (brazed joint). I believe it was noted that the glow plug is nickel plated - might be difficult to see a brazed joint under a coating.
 

b1mmuo27

New member
The last pic in that group showing a side view of the sheared-off nut looks so much like a tubing fitting nut. If you're familiar with them, like nuts from the tubing fitting brands Swagelok or Tylok. Seems strange to me the nut would shear at a plane displaced from the plane of the edge of the hex faces unless there was a plane of weakness there (brazed joint). I believe it was noted that the glow plug is nickel plated - might be difficult to see a brazed joint under a coating.
Actually no. I have the champion one in my hand now. That is one piece, from the nut to the part where the electrode sticks out. I count 11 threads which would give about a 1/4" contact in the head. I know th rate of expansion is different for the aluminum vs the steel or nickel plated steel. I'm still trying to find if their is a corrosive reaction over time between the two different metals or why they are so tightly held in.:idunno:
 

abittenbinder

Doktor A (864-623-9110)
My Sprinter has 135K on it. It's an '05 bought in December '04.
The engine was at normal operating temperature & brute force was not needed. The front plug almost was finger tight. But now I know that it was just turning in the sleeve.
The big mystery remains: You initially wrote-"I'm still trying to find if there is a corrosive reaction over time between the two different metals or why they are so tightly held in".

If this glow plug is seized and you never applied the excess (or any?) torque to shear it-When did it shear and why ??? Doktor A
 

contractor

New member
Andy
Just a thought. In my automotive days, it was very important to post bake a nickel plated part to prevent hydrogen embrittlement. Hydrogen embrittlement severly weakens a part by making it much less ductile and reducing the tensile strength ... it short it can fail. I'm wondering if maybe this part(s) were not properly processed by the supplier? Perhaps changing the plugs at 50K is not necessary (I sure hope so because it sounds like a bear). I know this doesn't help the issue with the broken plug but it does offer some possible explanation. I am a big believer of moly anti seize grease, however, after reading this thread the whole procedure scares me:wtf:.
 

b1mmuo27

New member
When removing things ie the glow plugs force is a relative thing. How much is always the question. While increasing torque the plug starts to move. I will remind you I have taken glow plugs from a GM 6.5ltr & 6.2ltr diesel. They are in a cast steel block & they themselves are made of steel. A third of the size of these glow plugs. Not having removed them I applied enough torque to have them move. How much? I don't know as I didn't use a torque wrench. But if I thought they would shear that easily something would have changed. As a creature of habit my only reference was the plugs in the GM. These are longer & I would suggest not near as robust in design. Was their other design choices? Could the make up air have been heated? As I have said my Renault turbo diesels are started that way. They are essentially a MACK block marinized by Renault.:hmmm:
 

b1mmuo27

New member
Andy
Just a thought. In my automotive days, it was very important to post bake a nickel plated part to prevent hydrogen embrittlement. Hydrogen embrittlement severly weakens a part by making it much less ductile and reducing the tensile strength ... it short it can fail. I'm wondering if maybe this part(s) were not properly processed by the supplier? Perhaps changing the plugs at 50K is not necessary (I sure hope so because it sounds like a bear). I know this doesn't help the issue with the broken plug but it does offer some possible explanation. I am a big believer of moly anti seize grease, however, after reading this thread the whole procedure scares me:wtf:.
I too am an contractor-electrical. I won't say it's easy, but to think your going to put a 10mm 1/4" deep socket on those glow plugs & just screw them out I think you should be aware of what could happen. Doktor A: would a torque wrench set at ? to remove these things be now advisable? If they don't crack out at that torque setting then don't proceed without thinking of how to loosen them or you'll end up like me. :clapping:
 

contractor

New member
I don't know if what I'm about to propose is even possible, but I bought a makita 18V impact driver and I love this thing. It takes so much less effort to install and remove screws because of the impact mode. It also easily takes wallboard screws out were an ordinary drill would twist the head off the screw. Is there room to use a tool like this instead of the standard rachet wrench?
 

b1mmuo27

New member
I don't know if what I'm about to propose is even possible, but I bought a makita 18V impact driver and I love this thing. It takes so much less effort to install and remove screws because of the impact mode. It also easily takes wallboard screws out were an ordinary drill would twist the head off the screw. Is there room to use a tool like this instead of the standard rachet wrench?
I've got a Milwaukee 18Volt lithium impact driver as well. I tried it. You could try too but I think the pounding by the impact driver wouldn't have the same desired effect on the glow plug as just straight torque & I think the torque on these plugs would be a little greater than what the driver could apply. There is definitely enough room if you have the 2.7, at least on the first 2 pulgs you just need an extention to get on them. BTW Milwaukee has that new cordless lithium screwdriver too. That's the greatest thing since sliced bread. :thumbup:
 

Altered Sprinter

Happy Little Vegemite
If you guys are really interested, I will underwrite in part as to the data that pertains to separate countries as to no one data file being identical etc. Daimler AG has extensive archival information that shows in this instance,as to why a recommendation is suggested for pre-preventive failures with glow plugs it is one of many issues that Daimler AG deals with at different intervals with data ,for maintenance schedules.

The PDF is encrypted so I can not down load this , for general viewing as to Daimler AG information for x amount of reasoning but where not copyright is so concerned, but to Daimler AG' protecting their intellectual rights to technologies. In brief as modern computer systems expanding with data, there is an ever increasing demand with data information as each year passes, the data is added to which increases the likely hood of errors via a computer command systems we have these on the NAG transmission etc.

Diagnostics for Germany, Australia N/America South Africa,etc use different parameter's of data for engine maintenance for each region, based on Temperature , Elevation, fuel quality, and oils etc, this is just a snippet as to How advanced an engine program can be altered to a region.

Daimler has been working on this for a fool proof error free system it is in part already operating on another vehicle of Mercedes-Benz vehicles commercial unit.

One can only program a system if the system is working in synergy with it's programs that have been throughly tested. that comply to a rating of tolerances elevations of temperatures with the correct fuel bar set, in part Fuel in the N/American sector has been an issue as to being inconsistent. as to extreme variations of the ASTM standards, Winter is an issue and there is a full quotation from D AG that covers this in full.

I could equally argue as to dealer ships failing to pass on informations to it's staff and technical work force. or say it maybe was never read! or understood in part...Dealers can apply for training programs..and for updated information this is not free, there is a minimal charge for the service, to cover the basic costs of the programs for it's students!who wish to advance in the increasing technology of learnings from Daimler AG ....It is not free.

This does entail equipment to be upgraded another cost! the dealer has to pay for this, if it's not done then how can a mechanic or technician throughly commit to undertake, said works in a professional manor if the operative has not been fully trained, and or provided with a continuance of upgraded information, and the correct tools of technology that is required to execute the works be it a repair, or an electronic reset.

If you want a write up I will do it over a two day period as to cutting the information down 5 thousand pages I can not do, I can also help to explain in part,, as to where errors come into play from programming etc.
Canada has temperature elevations as to seasonal changes to deal with, High sulfur fuels even with ULSD if it's being used bearing in mind the ULSD fuel is recent as opposed to extremely poor quality Diesel, that has no additive provided to help keep the engine in prime operating conditions.
This is not a Daimler AG problem with the Sprinters proper, but as to NAFTA agreements for local content, and how the sprinter was set for the N/American system.
The Sprinter is not perfect, but the problem to correct procedures of servicing,is underlying with tiered Management and it's own policies. that conflict to D AG and it's operations.
A mechanic technician can take up to seven years to learn his trade that covers every single section to service and maintain a Mercedes-Benz group of varied products these guys earn top dollar and have earned the right to command a high wage return any Fully qualified MB trained operative can demand his own wage:rad: especially in Diesel engines after eight years of being on the job, He or she does his apprenticeship, and the world is his oyster if he or she so chooses to pursue a career of advancement with-in the ranks of Daimler AG and it's extensive network of design manufacturing ,and with in partnership with it's aligned subsidiary's, are available world-wide, to put you in a start position from the shop floor, that can take you to the very top of the COE's. 4 years of low wages, after hours studying exams you name it...these guys, deserve the respect they are entilled to..They worked for it and the rewards that follows. Listen to the Doctor=Andy
Richard.
Augmented reality, a virtual on-line world to knowalge.

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abittenbinder

Doktor A (864-623-9110)
When removing things ie the glow plugs force is a relative thing. How much is always the question. While increasing torque the plug starts to move.

Not having removed them I applied enough torque to have them move. How much? I don't know as I didn't use a torque wrench. But if I thought they would shear that easily something would have changed.
Upon your clarification-there is no mystery.

You thought you had "broken loose" the 2 glow plugs but had actually sheared them. You then thought you had fully unscrewed them and were baffled - for some reason they would not come out of their bores-that's when you posted your plea for help. They were actually spinning in their sheared bottom halves.

It is likely they were not weakened (or flawed) before the removal attempt-rather it is highly likely the cyl head was not warmed enough(winter temps) and because of that, too much force was applied to the wrench-shearing the plugs.

It's a shame this scenario was repeated with the second glow plug. At least it's now limited to two. Doktor A
 

acvr4

New member
Wow I guess I better be real careful when I check mine :hmmm:
Since it's an not a constant problem I haven't addressed it.
It's great that you guys have post the procedure on the best way to remove them :thumbup:
 

talkinghorse43

Active member
My you-tube savvy son found this today. The featured tool kit likely costs more than a Sprinter replacement engine. Doktor A
Great find! In addition to the expensive tooling, this would be hell to attempt in place; looks hard enough on the bench. If I absolutely had to remove the offending glow plug, I would certainly try drilling a little to allow the biggest possible backout, then cooling with liquid nitrogen and attempting with the backout first.
 
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abittenbinder

Doktor A (864-623-9110)
My you-tube savvy son found this today. The featured tool kit likely costs more than a Sprinter replacement engine. Doktor A
Yes- it would not be possible to perform this extraction of a glow plug in the rear cylinders with the Sprinter engine in place. Even the removal of a fuel injector in the rear 2 cylinders requires lowering the engine for working clearance. Doktor A
 
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