I Removed and Replaced Six Glowplugs successfully.

Duc_pilot

New member
I'd like to share my experiences related to this task. For Context: I am not an professional Mechanic. Your results may vary. You are warned.

I got a MIL Code for the #6 Glowplug. As I do, when I have a problem for one thing out of six... I'll fix all six. So I read everything every written about glowplugs. Bought the special pliers, and special glowplug swivel sockets, 7 new glowplugs, and 8 connectors and clips. I didn't have enough faith that I wouldn't break something, so I had spares on hand.

My 3500 Long, Tall Sprinter has 170,400mi. It is USA lefthand drive. I count plugs 1-3 on the right side, passenger, front of engine to back and 4-6 on the left side, driver, front of engine to back. My Plugs are 4v steel.

Before you start: Have your replacement glow plugs and replacement connectors including the solder-on clips. Have the special plug pliers. Have a can of PB Blaster. Have a high-watt solder iron, solder, contact cleaner, and possibly some heat shrink tubing. Get some anti-seize and dielectric grease. have a compressor with a fine blower attachment.

Task 1 - Expose the glow plug connectors. I'd hope this has been covered elsewhere. If you have trouble with this operation, you may want to consider not going after the plugs.

Task 2 - Remove the connectors. Now, this seemed like it was going to be the easiest part of the project, but proved to be the most difficult. I had the special pliers and I could get a grip on all six connectors but: #1 came off pretty OK with difficulty increasing numerically with #2 and #3 being the last to pop off intact. #4-#6 required (Image 0) Dremel Attack. The connectors could not be removed without destruction. When I got the plugs out, I understood why.

Task 3 - Now with the plug exposed. Blow out all the schmootz and connector debris that accumulated around the plugs (you did remember to seal off all the exhaust/turbo piping - yes?). Now: PB Blaster. I attach a hose to the nozzle and give a shot around each plug. And here's the most important step: Now walk away. Let it soak for as long and you can stand it, then take a look, and walk away again. I let mine soak overnight, blew out the area with compressed air, and gave them all a fresh shot of Blaster - and walked away.

So here's where opinions and my experience collide. EVERYthing I've ever read warns: Do not attempt removal of plugs on a cold engine. I wondered just how hot the motor would be after the hour or more it takes me to get the intake parts off. I wondered what codes would get thrown with six plugs disconnected.... and so on. SO...

I made a play for the least corroded plug first: Plug #1. I figured if it snapped, I could at least get a removal tool on it and learn about drilling out broken plugs. I put a six-sided, long socket on an extension, no swivel, with a 6" wrench (Image 1). And with the torque available from one finger as shown... I gave it a go. Nothing moved and nothing snapped. I walked away. I blew out the plug recess, and gave it another shot of Blaster. After an hour I could wait no longer and gave it another try. IT BUDGED.. maybe 15 degrees. I walked away. 20 minutes later, it turned 90 degrees, and I turned it back in 45 degrees, added a fresh shot of Blaster and waited, then turned it out one full rotation. Then I waited. Then I back the plug out completely. I had the first plug out and in my hand. So I put it back in finger-tight, and moved on to Plug #2.

And repeat the sequence 5 more times. All plugs came out. All new plugs went in with a dab of anti-seize. I tightened them with the same 6" wrench, snug like a spark plug.

When It came time to replace the connectors, I inspected and reinstalled #1-3. I replaced the connector for #4-6. The wire needs to be cleaned with contact cleaner, fresh copper exposed and a new clip liberally soldered on (Image 5). The grey connector just snaps on. When I reinstalled the connector, I put a dab of silicon dielectric grease on the clip.

So the whole connector removal hassle is related to the corrosion of the clip (Image 2 and 3). The original connector cannot be cut, broken or crushed, it's too soft. My only hope to expose the Plug was to hack the connector apart.

There you have it. My observations: Blaster is amazing. Be Patient. Don't always believe what you read. I got lucky.
 

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Mickyfin

Member
Well done, and thanks for sharing your experience and tips, certainly something I will do myself when needed.
 

sajohnson

'09 View/08 3500 chassis
That's one hell of a first post Duc_pilot. Great job -- and right on time! I'm getting ready to replace all 6 glow plugs in my 2008 Sprinter.

I'm glad I read your post because I was thinking all I'd need is the plugs.

What year is your Sprinter?

Any guess as to why connectors 1-3 were OK and 4-6 needed to be replaced? That seems odd.

Where did you purchase the connectors?

Were the special pliers necessary? Which brand did you buy?

Did you end up using the special glow plug swivel socket?

As an alternative to the swivel socket, I'm hoping a deep well, 6 point socket with a universal joint (if necessary) will work.

Which glow plugs did you use? I'm considering these from Bosch, $70 for 6 each:
https://www.amazon.com/gp/product/B00A9Z1BZ4/ref=ox_sc_act_title_1?smid=A3UDS6REYKUGIF&psc=1

I am glad to hear you had good luck with a cold engine. I was wondering the same thing -- by the time everything is removed to expose the connectors; then the connectors are removed (hopefully easily, but as your experience shows -- not always); then any dirt/debris is blown out from around the plugs; PB Blaster is applied and allowed to soak, the engine will be cold.

I plan to use a small (not very powerful) cordless Ryobi impact driver to loosen up the plugs, if moderate torque with a wrench doesn't do it.

Thank you for taking the time to post photos.
 

Ciprian

Spark Plugs not allowed!
I would recommend to invest in a torque wrench. Not doing so will bite you in the behind sooner or later.

Sent from my VS995 using Tapatalk
 

Duc_pilot

New member
Hey Everyone,

Here's some additional info:

For sajohnson

My Sprinter is 2012.

The 4-6 connectors needed to be replaced because they had to be destroyed for removal (Image 0, 2, and 3). The Clips were corroded onto the electrode. Why they were corroded, I can only assume had to do with them being on the hot side of the motor.

I'm not sure if this forum accepts posts with endorsements so I purchased my connectors, clips, and plugs from a dealer on the west coast, established in 1985, located between mexico and southern LA that deals in euro parts.

The special pliers were useful. The special sockets and reamers ended up not being used (but 6-sided deep socket IS required). They were both from an online shopping site (Image 2.3 and 2.4).

Plugs are a tricky thing to buy. There are steel 4.4V @ $13ea and ceramic 7V @ $43ea variants and your motor number is required to order the right ones... or at least mine was. The same shop where I bought the connectors was a big help with this. Am@zon may not be your best bet.

I'd absolutely avoid that impact driver idea - that was the whole point of my post. 6" handle, finger pressure, Blaster and patience.

For Ciprian

I not only have invested in torque wrenches, I plan to do a post where I torque my removed plugs to destruction to KNOW exactly where they will snap. I have a 6 unit sample the collect my data.

Additional Stuff to know:

I also required a set of female torx (Image 2.2) for removal of most of the fasteners under the hood. Some can be had with a 12-point but... right tool for the job, and all that. I also swished out the plug holes with Blaster and these small diameter, wire bottle brushes (Image 2.1). Both available on an online shopping site.

Thanks for your replies and interest this tricky operation. Duc_pilot
 

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sajohnson

'09 View/08 3500 chassis
Hey Everyone,

Here's some additional info:

For sajohnson

My Sprinter is 2012.

The 4-6 connectors needed to be replaced because they had to be destroyed for removal (Image 0, 2, and 3). The Clips were corroded onto the electrode. Why they were corroded, I can only assume had to do with them being on the hot side of the motor.

I'm not sure if this forum accepts posts with endorsements so I purchased my connectors, clips, and plugs from a dealer on the west coast, established in 1985, located between mexico and southern LA that deals in euro parts.

The special pliers were useful. The special sockets and reamers ended up not being used (but 6-sided deep socket IS required). They were both from an online shopping site (Image 2.3 and 2.4).

Plugs are a tricky thing to buy. There are steel 4.4V @ $13ea and ceramic 7V @ $43ea variants and your motor number is required to order the right ones... or at least mine was. The same shop where I bought the connectors was a big help with this. Am@zon may not be your best bet.

I'd absolutely avoid that impact driver idea - that was the whole point of my post. 6" handle, finger pressure, Blaster and patience.

For Ciprian

I not only have invested in torque wrenches, I plan to do a post where I torque my removed plugs to destruction to KNOW exactly where they will snap. I have a 6 unit sample the collect my data.

Additional Stuff to know:

I also required a set of female torx (Image 2.2) for removal of most of the fasteners under the hood. Some can be had with a 12-point but... right tool for the job, and all that. I also swished out the plug holes with Blaster and these small diameter, wire bottle brushes (Image 2.1). Both available on an online shopping site.

Thanks for your replies and interest this tricky operation. Duc_pilot
Thanks for the follow-up!

You mentioned using your old plugs to determine shear torque. FWIW -- this NGK video has a chart listing shear torque for various size glow plugs. Queued to 1:26:
https://youtu.be/W9lzWWGj8LM?t=86

It will be interesting to see how your results compare.

I realize the impact driver sounds like a risky idea. I thought of it a while back, when I kept reading about people snapping off glow plugs -- mostly in the I5 engine. I had already used the impact driver successfully to loosen seized hardware but wasn't about to be the first one to try it on glow plugs. Then a couple months later I read a few posts by well-respected people (including a couple Sprinter mechanics) who had the same idea, and said it worked well. I believe most were working on the T1N Sprinter with the I5 engine. From what I've read, the V6 glow plugs generally come out much easier. I'm guessing yours were more difficult because your Sprinter has over 170,000 miles.

I plan to use your method first. I have plenty of time to 'walk away'. There's no rush.

Hopefully I will not have to use the Ryobi impact driver, but used judiciously (dialed down) any sort of impact wrench/driver is more likely to loosen stuck hardware without twisting it off than steady torque from a wrench. At least that's been my experience. The cordless impact driver isn't anywhere near as powerful as an air gun -- and the force is variable, down to well below what's required to break glow plugs. What people report doing is using light force over several minutes, then (if necessary) reapplying PB Blaster, letting it soak for a few hours, and trying again.

Did you use both of the special pliers shown? I ask because the ones I've seen have all been curved.

I went to the site you bought the plugs from and found this:

"2007-Mid 2012 Sprinter 3.0 V6 Glow Plug"

"For model year 2012, these steel glow plugs were used up to June 15, 2012 thru engine number 41330713. These are a 4.4 volt plug and NOT a 7.0 volt plug."

That explains why the engine number from your 2012 Sprinter was needed.

Your original post was clear. I understood that you had to destroy the 3 connectors, and the photo made it obvious why -- a poor terminal design by MB. I was focusing on why only the 3 terminals on the driver's side were seized. You mentioned more heat on that side, that's a good theory. I wonder why that side is hotter?

My 2008 cab-chassis has about 90,000 miles on it so hopefully things will go a bit easier.

Thanks again for the information.
 

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