How-to correctly remove a stuck diesel Duramax glow plug - Mechanics Minute

[@CarlAWeiss-je2oc]

Thanks for this tip, I had to replace all 8 glow plugs on my Lb7 and ended up using the air hammer attachment for all 8! All came out and not one broken glow plug. Merchant you saved the day.

[@briandaniel1273]

Thanks

[@lieutenantb1070]

I just ordered the Merchant kit for my LLY, I have 2 GP's showing fault, not even taking a chance, I bought the kit. Thanks for the tip!

[@scottrubenstein4825]

Just wanted to take a moment and say thank you for this tip. Cylinders 5 and 7 were frozen on a C5500 bus and even snapped the glow plug 12mm heads off. I was successful using your method with some socket extractors, an 1/4" drive extension w/ a nut welded on the shaft, and my air hammer (short hammer head) w/ a 1/4" adapted welded on the end. Necessity is the mother of invention my friend! Happy New Year

[@bigD1988]

I'm a mobile mechanic myself. 24 years. Kroil is the nest penetrant out there

[@merchantautomotive]

Don't have much experience with it myself, but heard lots of good on it.

[@DRJMF1]

Excellent ideas, good idea of using vibration. Prior to inserting the new plug, you could have used a reamer with some grease to collect all the crap from the inside of the thread on the head block. You can soak the old glow plug in the head block for a few days in non silicone oil too and use the car...helps a lot...prior to removing the plugs from the head block. Thanks.

[@merchantautomotive]

Great tip! Most of the time with the Duramax, the issue is the threads not letting go but always a good idea to make sure the head is clean as well

[@eedom69]

Would placing the socket on the plug and using a small hammer to give it taps work in a similar way?

[@richardpeasley4519]

Thanks for the video demonstration. Both my Snap-On and Mac Tools dealers have this tool available.

[@merchantautomotive]

It is a great tool for sure, and when used properly can be a huge help.

[@jasonm5245]

This method needed to be used on two glow plugs, the rear most on my 2002 LB7 (184K miles). The one on the R side came out fairly slow for about half way, and needed air hammer to that point, and (oh crap!) pulled a thread. The one on the L started slow for about 2/3 of a turn, then freed right up to where it could be removed by hand. The other six did not need the air hammer method. So, that pulled thread in the R rear most opening....could only drive the new plug in 1/2 way before it bound. So, I took the old glow plug and chased it with a 10 mm x 1.25 die nut. Then, with my Dremmel tool, I cut two longitudinal grooves in the threads (inner half), 180 degrees apart, and sharpened the remaining "V" groove with a file. i used this as a tap, driving in 1/3 way, removing, 2/3 way remove, and the rest of the way. I removed debris with a smaller diameter tap wrapped in a paper towel. The as left opening looked clean. This successfully restored the threads so that i could drive the new glow plug home without exceeding the max torque of 13 lb. ft. till it seated. kudos to Merchant Auto. The only bad was I ended up with a bit of surface galling on the perimeter of the glow plug opening. But, it sure beats the heck out of a broken glow plug. Thanks!

[@merchantautomotive]

Glad to hear you got them out. You never know what you getting into until its time to take them out. We have had lot of experience taking these out and glad out kit can make it an easier job. Thanks for watching

[@chadwalters5469]

i made myself one of these tools. its unbelievable how easy it was to remove the glow plugs without breaking them. and here in canada thats saying something worked amazingly definitely recommend this tool

[@powpirate]

Excellent video! I will be trying to find one of those impact adapters. Great tool! Thanks for posting!

[@user-po9sg3ks4p]

What do you do if they the glow plugs have been in for years ?

[@charlesrobitaille1180]

Very helpful, i did the job with success. I used the tool on all of them, i didnt want to take a chance breaking them. Just used pressure with the wrench and came out easy! The hard part was to reconnect the wires, grind all the ends because them little bolts would break off!! Also i was able to do the job without having to remove any coolant pipes... pushing on them a bit.

[@bdfarmer1959]

Very helpful video, thanks for taking the time to share your knowledge.

[@trusso2614]

that tool is bad ass, I spent 2days drilling and screaming at the glow plug out, you have to tell us where to get that tool! I'm sure any dmax owner would buy one

[@merchantautomotive]

There is a link in the description to purchase

[@charlesrobitaille1180]

The tool is called a shake and break, commes in a set of 2 3/8- 1/2 inch drive. It does vibrate the block and mark it a bit but no big deal, has you put pressure on the wrench, the vibration is transferred to the plug.

[@scientist100]

I kind of noticed that it wasn't hitting the plug directly but rather the bottom which would be the block, would it better to install the 10mm back flush to the plug and use a short 12mm socket to hit the plug directly? I believe the taps shouldn't need to be too aggressively.

[@shaunbrown1402]

Great technical advice.

[@jimbosammy4255]

One can also do this with a battery impact drill. Just set it to the lowest setting and let it vibrate. Slowly increase the power of the impact and they will usually back out. Go slowly and let the vibration do the job. Some have taken 90 seconds to work loose.

[@Dead-Goldstar]

Great video can you tell me the specs on torquing the glow plug back in.Thanks 👍

[@merchantautomotive]

18-20 ft lbs is adequate

[@shawnsmith4058]

What type of penetration spray did u use ?

[@julianarodriguez3635]

Will this tool work on a Toyota hiace from the Philippines let me know thanks

[@gunlover1955]

I do the same thing with my 3/8" impact and very low air pressure in and out go slow, in first then out it works very good the hammer vibration is what helps.

[@sirsweetness8332]

Is this a normal 6 pt 12’mm socket? Or is the end machined to vibrate the plug itself? It would seem that a regular deep socket would just vibrate the head and not the plug itself.

[@merchantautomotive]

We machine our socket so the socket bottoms out on the head of the glowplug. A normal deep or medium depth 12mm socket will hit & damage the head.

[@merchantautomotive]

Duramax Glow Plug Removal Tool Kit | 2001-2016 vehicles. www.merchant-automotive.com/Glow-Plug-Removal-Tool-Kit-LB7-LLY-LBZ-LMM-LML-2001-2016

[@johngrein3325]

Trying to figure out how the socket sliding up and down on the glow plug hex due to the hammer transmits much shock value at all to the threads. Have to be careful to keep the socket (6pt of course) on the hex without hammering on the cylinder head. Sounds like it works great though.

[@marcusmason3440]

Neat trick.......out in to the workshops to give it a try. Five out of six plugs locked solid in an om606...tedious.

[@merchantautomotive]

Very tedious

[@eedom69]

What if u don't have an impact or air tool? These things won't move

[@Franklinveterinarycenter1of4]

Just curious, why does manufacturer repair manual say "don't use antiseize on glow plug threads". Also, why use "copper antiseize" instead of standard antiseize?

[@enginedoc5988]

I suppose because people would put all sorts of stuff onto it and since they are glowing hot, it can worsen the situation in many cases.

[@garydooley9919]

Hi . I have an old FJ40 and think glow plugs may never have been changed. They are marked and scratched on bolt a lot. Threads come undone easily but glow plug will not come out of hole. What would you recommend ?

[@merchantautomotive]

It's possible the tip is swollen and this is keeping it from coming out.

[@copedennis1]

Does anyone have a solution on getting them out when it’s unscrewed but still won’t come out?

[@merchantautomotive]

@@copedennis1 The tip is likely swollen. Care must be taken when trying to get them out so as not to break the tip off in the cylinder. You might be able to pull it out with a bit of force, but just have to be careful not to break it off. May end up needing to remove the cylinder head worst case

[@BadDadio]

Excellent video; thanks. Especially helpful are stating the socket sizes. Any tips on pulling the wheel wells? Some comments below have some good tips too.

[@merchantautomotive]

We do offer a tool to aid in removing those clips as well as replacement clips if they get damaged.

[@sidescrollin]

I don't get what this is doing over a regular socket or impact. It's adding a hammering action forward and backward, but I don't see how that would prevent damage compared to using a plain 6 point socket

[@BadDadio]

Ian Mcdowell An impact wrench puts torsion on the threads which may break them. The impact puts vertical loads on the threads to help break them free. Also, using the wrench manually provides better torque control and doesn’t force rotation as would an impact wrench.

[@marklawrence5158]

I am working on an LB7 with a seized #8 glow plug. I have the same air hammer and bit as you showed, but it looks like I won’t be able to get square on the plug due to the cab. Any other suggestions besides soaking it for days with penetrating fluid? I tried to budge it both directions but it seems to start twisting. I really don’t want to break it off, especially on #8

[@Chevelle-oz7bj]

Mark Lawrence I

[@duramaxbradentonsaltwaterf9471]

How serious is this problem? Do i have to fix asap

[@martytaylor9820]

Where do i get one of those tools?

[@bigjimmy2225]

Merchant automotive probably

[@peteragersea377]

That glow plug looked new . Mine had so much carbon on it it would not come out . The threads pushed it out a little but the carbon was holding it in . So after going in and out soaking and pulling while turning yelling at it for an hour. I just started it and it shot out like a bullet.

[@angeloayuyu4059]

How do you remove one that turns but does not come out?

[@copedennis1]

I have one now like yours. Lose but still won’t come out. Fought with it two hours. Tried starting truck and still won’t come. I know it’s loose because I can move it up a d down. It’s very hard to turn by hand

[@mitzxx8995]

What if #8 glow is stuck ? Your not getting that air hammer in there.

[@merchantautomotive]

That sure makes it tough, but an extension can be used between the socket and the air hammer. Not a perfect scenario but should help some

[@brianrodemeier5786]

Just use a 3/8 impact, best of both worlds. The hammering affect and the reverse motion will get it out.

[@TrevorAdamsDoesSkate]

I recently changed all 8 glow plugs with the air hammer and at times help with an extension. Awesome tool. 2005 LLY 135k

[@issacdavis3767]

I have a 6.2 in my 1990 m998 humvee. How much would a shop charge me to replace all 8 plugs?

[@merchantautomotive]

I would not be able to help you with that, my best advice would be to find a local shop in the area that is familiar with that setup to get quotes

[@johnnyz1781]

What is the torque spec?? >_

[@kenshinhimura9387]

doesn't matter. Just make em snug

[@wullierennie3190]

Don't go over smug

[@Lettersandstuff]

Use a propane torch before you touch the glow plugs... it makes this much easier and you won’t break anything

[@CitrusFunk]

Hey seriously thank you, that saved me a lot of work. I dont have the money for a compressor and an air hammer. Hell yeah

[@brianburke396]

Great tip, thank you 👍👍👍

[@merchantautomotive]

www.merchant-automotive.com/searchadv.aspx?SectionID=0&SearchTerm=glow+plug+removal&ShowPics=1 If the link changes just go to our website and search "glow plug removal. Thanks for watching

[@kenshinhimura9387]

Put antisieze on the threads and they will come out with a normal wrench.

[@ernier9033]

Use copper anti-seize, not the grey type shown in the video🕊

[@kenshinhimura9387]

lol glow plugs should come out very easily. You people are making the mistake of not applying antisieze before you install them. That's why you have trouble. ALWAYS use antisieze when installing glow plugs. Also when you are taking them out don't just turn them out. Go back and forth (loosen then tighten) a little bit at a time to make sure you don't break anything. PB blaster is your friend if they are stuck but you should never need it.

[@enginedoc5988]

Tell this to mechanic in factory who torqued them 30 years ago 😂

[@asdgasdf9580]

Now do the driver side! 😂

[@bparks_5095]

As a man who has replaced dozens of Duramax glow plugs, I would NEVER bring a power/air tool even within shouting distance of a stuck glow plug. You are asking to break it off. Even using an air chisel "lightly" like this makes me viscerally cringe. One wrong move and its all over. I tell people all the time, all you need is a warm engine, and plenty of proper penetrating oil. I've never found a power tool even remotely necessary even on the most rusted of glow plugs.

[@merchantautomotive]

Best of luck when you need to replace one on a truck in the rust belt!

[@xMods-ld8nx]

so whats the torque spec? to lazy to say it????

[@merchantautomotive]

Not all applications will have the same spec and our recommendation is to always refer to the proper service information for your specific application