Drilling out broken diesel injector from Cylinder head BMW M57

[MetalMonkey]

Whatever you try, take the head off first.

I'd give a solid 0% chance of not getting at least some bits of swarf or filings in the cylinder no matter what you do - and that will cause you a lot more pain in the long run than just pulling the head off to start with.
Once you have it on the bench, you will have better access and you might even get lucky by working at it from the other end.

 

[Franknstein]

A rotabroach with a pilot pin to match the internal hole would be my choice if I had to choose something off the shelf.
I can turn a suitable pilot pin/drill extension for one, if that helps.


My choice would be a decent geared cordless. You need enough torque to make decent chips or it will heat and blunt the drill.
A mag drill would be better but Ive never used one.


Nitric will eat ally! yes concentrated will passivate but it also does that to iron, so its not selective enough for this.
Alum (potassium aluminium sulfate) is the safe option that wont touch the casting - but it needs heat and is very slow!

Thanks for this Kram, I have found a mag drill for hire in my local area for £36 for a day - not too bad. I'd like to take you up on your offer of turning something for me - shall I PM you?

 

[HydrocarbonPrimate]

If the Tip is out the only thing holding that in is carbon, i would get some oven cleaner in there but it does eat auminium so maybe not full strength, then wipe out with rag on stick, then a little brake cleaner,then i would give it some light taps with a long chizel or 3/8 extention bar and see if you can get it to move. A chemical solution is worth trying before a getting swaft in cylinder.

 

[maroon]

close the valves. get the piston to the top and throw diesel into the chamber submerse it and let the whole thing soak.
on that existing hole. weld and extractor bit on a T piece. (two conrods kicking about?) wind it in and pull.
or tap a thread into it and a long bolt. something to that nature.


that would be my first attempt.

Ali. do not use heat.

 

[Kram]

Any swarf that does get in, is likely to be vaporised and/or pinged out the exhaust port instantly.
I got some mig splatter in the first pot of my CBR600, was still running 85k miles later. There are many little dents on the piston that likely all happened in the first mile.

Thanks for this Kram, I have found a mag drill for hire in my local area for £36 for a day - not too bad. I'd like to take you up on your offer of turning something for me - shall I PM you?

Sure PM me. I have been looking for an excuse to use the lathe.

You may have a problem finding a cutter and shank extension that will fit in the injector bore but I can probably adapt one to fit. They are normally 3/4" male shanks into a female socket. I have a 24 and 26mm with baby 1/2" shanks but I dont know where to get 16mm.

 

[Franknstein]

Any swarf that does get in, is likely to be vaporised and/or pinged out the exhaust port instantly.
I got some mig splatter in the first pot of my CBR600, was still running 85k miles later. There are many little dents on the piston that likely all happened in the first mile.


Sure PM me. I have been looking for an excuse to use the lathe.

You may have a problem finding a cutter and shank extension that will fit in the injector bore but I can probably adapt one to fit. They are normally 1/2" or 3/4" male shanks into a female socket.

Yeah, I just looked for extensions, seems the RD2103 would do (https://www.rotabroach.co.uk/products/power-tool-accessories/extension-arbors/) - but probably needs to be turned down as the diameter is too large - But its £176!

 

[James1979]

Any swarf that does get in, is likely to be vaporised and/or pinged out the exhaust port instantly.
I got some mig splatter in the first pot of my CBR600, was still running 85k miles later. There are many little dents on the piston that likely all happened in the first mile.


Sure PM me. I have been looking for an excuse to use the lathe.

You may have a problem finding a cutter and shank extension that will fit in the injector bore but I can probably adapt one to fit. They are normally 1/2" or 3/4" male shanks into a female socket.

Wonder if you could TIG a 3/4” round straight onto the cutter? If you turned a long spigot which doubled as a guide pin?
You’ve probably thought of that

I did actually wonder if you’ve got a long guide pin which is a good fit and a round bar which is snug in the bore welded onto a good sharp cutter wether you’d do it by turning by hand? It would be kept aligned by three point contact as it were

 

[Franknstein]

close the valves. get the piston to the top and throw diesel into the chamber submerse it and let the whole thing soak.
on that existing hole. weld and extractor bit on a T piece. (two conrods kicking about?) wind it in and pull.
or tap a thread into it and a long bolt. something to that nature.


that would be my first attempt.

Ali. do not use heat.

I have thought of using an easy-out as suggested, problem seems to me is that it will thread itself into the head, perhaps I can find a bigger one than I currently have, its worth I shot I think before I get onto drilling! Thanks for this.

 

[James1979]

I have thought of using an easy-out as suggested, problem seems to me is that it will thread itself into the head, perhaps I can find a bigger one than I currently have, its worth I shot I think before I get onto drilling! Thanks for this.

Look for the 1/4 turn square ones. I’ve a snap on set. They’re good at this sort of stuff

Edit. These are mine. Crap pic https://www.ebay.co.uk/p/1525086156

 

[maroon]

I have thought of using an easy-out as suggested, problem seems to me is that it will thread itself into the head, perhaps I can find a bigger one than I currently have, its worth I shot I think before I get onto drilling! Thanks for this.

don't forget to lower the piston when doing it. just raise the piston so you're not having to fill a whole chamber when putting easing oil in. syringe that back out.
do an oil change afterwards.

might work, might not, depends how wedged it is in there. worth a shot though imo. not having to pull the head off.

 

[Kram]

One of these baby cutters, 1/2" shank which would fit in there just about with a brazed extension, but they dont have 16mm. I have a 24 and 26 and they are very good but unless anyone knows somewhere with more stock..

BABY AIRFORCE ANNULAR ROTABROACH TYPE HOLE CUTTERS | JANCY | SLUGGER | eBay UK

Jancy AirForce Baby Slugger Cutters / RotaBroach Style Annular Hole Cutter. Jancy Engineering is proud to introduce its Short Slugger series of annular cutting tools. - 1/2" shank for use with pneumatic Airforce drill.

www.ebay.co.uk

Wonder if you could TIG a 3/4” round straight onto the cutter? If you turned a long spigot which doubled as a guide pin?
You’ve probably thought of that

I could but that doesnt change a 3/4" is not going to fit in the injector bore, so the cutter shank would need to be turned down and fitted/brazed onto a long extension with the guide pin.
It may be easier to make a cutter from scratch. I have some hss blanks.

 

[DAPPH]

This idea is based on a military vehicle canvas canopy frame joining pin, the offset has to be aligned to get it through the fitting hole. once through and out the other side you rotated it back 1/3 to 1/2 a turn and a spring wire dropped into a locating grove to hold it in place in the now offset tip form.

Could this idea be developed to make as thick as pulling rod as possible in a thin sleeve to be put down the broken injector hole, make the offset slug 10 mm or more from top to bottom, thread it so it will sit parallel with slip in slide bolt and tack weld it to the threaded rod
I'd also pump the cylinder with the piston at BDC with grease to stop any crud falling in the cylinder slip the extractor in rotate it 1/3 of a turn to set the extractor slug in the right position so it can be used to knock the tip out from underneath and gently use a slide hammer on the bolt threaded end to tap it up from below to free it . two
When out clean the hole and seat well use a brass brush if needed etc . then when it's clean and polished gently turn the engine over by hand to expel the gungy grease .. Once it's all out pour some paraffin in the cylinder w few inches from when the postonn in now back off to a few inches below top dead centre then cover the area in absorbent material and turn the engine over on the key a few times to blow out the rest of the grease before it the paraffin melts the grease.

 

[Melvyn Best]

Personally I would try spraying the remains of the injector with an air intake/carbon cleaner aerosol then use an injector seal removing tool, the type with a tapered thread and a slide hammer, £16 off of eBay before any attempt at drilling

 

[arther dailey]

either way a lot of us have been in a similar position , so please lots of pics which ever way it turns out it will help others , to clean injector bores I found a bronze brush for cleaning 20 bore shotgun barrels was the perfect solution .

 

[ajlelectronics]

I would be taking the head off and taking it to someone who does it for a living.

 

[scottmk1]

After answering your post on FB, I’d favour most answers on here. Take the head off and do the work using a much beefier guide or go to a machine shop and have them remove it.

 

[Kram]

This popped up on ebay, looks like it needs a threaded arbour which should be easy enough to get or make.

https://www.ebay.co.uk/itm/193548703550

There are 16mm ones for a bit more, 5/8" is probably a good choice.

 

[maroon]

Tbh I wouldn't touch it with a drill. Too much of a risk cocking the head up with it being Ali. If you can't get it from the top. Take the head off and knock it out hammer and punch from the other side. Needing gaskets and all the other stuff. But that'll be cheaper than a new cylinder head after attacking it with the black and decker.
When you've got the head off 2400 with old engine oil (or new) on a wooden stick to polish the bores.
Like wet and dry but use oil to wet it.

Bit of grinding paste on some fluffy string and/or on your finger.

 

[Tinbasherdan]

Wonder if a rawl bolt or similar would grip the inside of the body? Weld one to a slide hammer to get a good grip and give it the good news

 

[graffian]

I took a broken injector out of a head.
The injector was well stuck and the thread snapped off it.
It was taken to an "expert", who snapped a milling cutter in it.
I set about it with battery acid and a battery charger.
It removed the cutter and injector leaving the hole clean and lightly anodised.