2 injector clamp bolts snapped in hole, 2010 Mercedes E350 3.0 V6 . What should I try ?

Page may contain affiliate links. Please see terms for details.

KramEkard

Active Member
Joined
Jul 25, 2023
Messages
65
Location
Lancashire
Car
2010 Mercedes E350 3.0 v6
I've been replacing the fuel injector seals on my 2010 Mercedes 3.0 V6 I been at it for 2 weeks solid, in process I snapped the plastic that the leak off pipe goes onto so had to replace 2 injectors, alao broke the leak off pipe so had to replace that as well.
I'd finally about finished and only thing left was to torque down the injectors.
I have never used a torque wrench so a neighbour set it on the tightening sequence I told him it should be 8 nm.
So I was torquing them down when I heard a snap
The bolt on the injector clamp had snapped about half way in , on 2 of the 6 injectors.

Does anyone have any idea how I can get the snapped by out ? What about whacking a nail with a lump hammer on it to chip away at it ?

Apparently my mate thinks by looking at the torque wrench he says it looks as though my neighbour set it at 58nm instead of 8nm !!
 
Last edited:
I've been replacing the fuel injector seals on my 2010 Mercedes 3.0 V6 I been at it for 2 weeks solid, in process I snapped the plastic that the leak off pipe goes onto so had to replace 2 injectors, alao broke the leak off pipe so had to replace that as well.
I'd finally about finished and only thing left was to torque down the injectors.
I have never used a torque wrench so a neighbour set it on the tightening sequence I told him it should be 8 nm.
So I was torquing them down when I heard a snap
The bolt on the injector clamp had snapped about half way in , on 2 of the 6 injectors.

Does anyone have any idea how I can get the snapped by out ? What about whacking a nail with a lump hammer on it to chip away at it ?

Apparently my mate thinks by looking at the torque wrench he says it looks as though my neighbour set it at 58nm instead of 8nm !!
Wow a lot of difference between 58 and 8.
 
There are special tool sets for snapped bolt removal. Injector bolt hole is just very deep so not all tools can reach the bottom (if needed).

Yep, you need very small torque wrench for those (larger wrench range is not even starting from so low values, or at least it is very inaccurate).
 
There are special tool sets for snapped bolt removal. Injector bolt hole is just very deep so not all tools can reach the bottom (if needed).

Yep, you need very small torque wrench for those (larger wrench range is not even starting from so low values, or at least it is very inaccurate).

Are the tools easy enough to use, and would tapping at the bolt with masonry nails and a lump hammer work ?
Thanks
 
would tapping at the bolt with masonry nails and a lump hammer work ?

If you think the above is a viable solution to the problem then i would be shutting the bonnet before i caused any more carnage.

On a serious note , if you dont know the difference between 8 + 58nm then it maybe the time to get someone involved who does , and not the neighbour.

K

PS - 01/04 is tomorrow.
 
If you think the above is a viable solution to the problem then i would be shutting the bonnet before i caused any more carnage.

On a serious note , if you dont know the difference between 8 + 58nm then it maybe the time to get someone involved who does , and not the neighbour.

K

PS - 01/04 is tomorrow.

I just torqued down the other 3 injectors and it seemed fine but I used a different torque wrench that this time my mechanic friend set for me .

I had a pick and that went into the bolt when I hit it with the hammer but it later bent so I'm wondering would I be able to do the same with masonry nails because they're a lot stronger ?
 
I had a pick and that went into the bolt when I hit it with the hammer but it later bent so I'm wondering would I be able to do the same with masonry nails because they're a lot stronger ?

I think what you are actually looking for is a centre punch and a small ball pein (engineers) hammer.

K
 
I think what you are actually looking for is a centre punch and a small ball pein (engineers) hammer.

K

Idk what that is I may look into it, are those easy out kits from Screwfix etc quite easy and efficient to use for the application?
 
are those easy out kits from Screwfix etc quite easy and efficient to use for the application?

Depends on the access and who is wielding the power drill and using the extractor.

What size are the original bolts ?

K
 
Depends on the access and who is wielding the power drill and using the extractor.

What size are the original bolts ?

K

Access is really good as in can get over the hole easy enough and I was planning on using the drill
 

Attachments

  • Screenshot_20240331-112149.png
    Screenshot_20240331-112149.png
    304 KB · Views: 13
You will only get one shot with the drill, any damage to the threads if the drill runs off centre will mean having to fit helicoils. This aasumes that you can get the broken bolts out.
 
You will only get one shot with the drill, any damage to the threads if the drill runs off centre will mean having to fit helicoils. This aasumes that you can get the broken bolts out.

What happens if I am unable to get the broken bolts out would that mean drilling it out ?

Also if it ends u needing helicoils is that a big procedure or something that can be done diy for a novice ?

Thanks
 
If you can't get the broken bolts out it is a specialist job. the danger is that you could do further damage. The best plan would be to just get the car to someone who has the right tooling to do the job. One method of removing snapped bolts is spark erosion, the aim is to remove the bolt with as little damage as possible to the head.

Sadly DIY jobs can and do go wrong, maybe time to cut your losses and learn from the experience.
 
Access is really good as in can get over the hole easy enough and I was planning on using the drill

A pic doesn`t really help , i was talking about the thread size in MM.

The smaller the thread size the more chance you have of making an (expensive) mistake if the drill runs off into the head , bearing in mind the alloy of the head is much softer than the steel of the bolt and the drill will follow the path of least resistance.

To use a screw extractor the initial drilling must be perfectly on centre and true to the path of the screw , you really need to know what you are doing or as a novice be extremely lucky plus you will need decent (expensive) extractors.

FWIW i have been using screw extractors for over 40 years and the success rate is less than 50% , plus if you break a screw extractor in the hole you are in deep doo doo as they are harder than Lenny (Bruce Lee / Norris) McLean and will need expert assistance to remove.

The issue you have is that it took six times the actual torque to shear the bolt meaning it is properly stretched and will be wedged in there tight , possibly too tight for an extractor to remove.

Fair play for having a go at the injector seals but some things are better left to sheared bolt specialists , regardless of the cost.

The lump hammer you mentioned previously is probably better used on your neighbour then disposed of a the bottom of the local reservoir.

K
 
Given that he has two snapped bolts he would need to get lucky twice with the drill. The odds on that would be interesting. Not sure which part of Lanc's the OP is in, but Princess Engineering in Manchester have done several bolt extraction jobs for me over the years and never failed to get a good result.
 
Once they snapped all the stretch should have gone.... they should come out easily.
 
anybody that has worked on cars should know what the torque is on a bolt also how to set a torque wrench, you could try drilling a small hole in the broken bolt then using an easy out

My mate says it's highly unlikely it'll work on such a small bolt, says we should drill out the bolt hole completely and then use a tap to rethread it .
Says using the easy out piece of that gets stuck in the bolt he says we'd have a much bigger problem
 

Users who are viewing this thread

Back
Top Bottom