[DynamicsZ]

A friend and I were going to change out the OFHG on his 2011 N51. The left lower bolt to the right of the mickey mouse flange ended up stripping after he decided to use an 8mm box wrench. He didn't want to take out the flange and ended up stripping the E10 bolt. Big regret as I told him to use an E10. The shortcut failed. Currently, he has sanded down the head to almost just the bolt shaft. When I tried to use an E10 in hopes of turning it loose, it seemed too tight. Here are the pictures of the bolt head and end of the thread. The first picture is the head. Looks like a battery. Can we use an extractor to drill it in and extract the bolt or take it to a shop? I'm just annoyed he took the shortcut route.

 

[littleredcar]

i'd try generous application of a WD40 like product, maybe with a bit of tapping to try and free it up. Application of heat if you can do so safely without melting anything nearby. High quality vise grips if you can fit them. Not sure if they make an extractor like socket that will grip what you have left. I'd try all that before drilling which can be difficult if you can't get straight on with your drill. Other readers might be able to tell you if this is an aluminum bolt (you can check with a magnet). If aluminum it would certainly be easier to drill than a steel bolt. But also weaker trying to crank it out with vise grips. Good luck

 

[littleredcar]

If you remove the housing over the ground down bolt you'll have better access to the leftover stub to grab it.

 

[effduration]

I suggest you pay someone who knows what he is doing to weld a nut on the remaining shaft and unscrew it that way.

you can also try an extractor that grips the outside of the shaft...not the inside, but they don't work all that well.

welding a nut is the way to go.

 

[SKWDMD]

Why not remove the other two bolts and see what you are left with. I would think since the head has been flattened the housing should come off. I don't recall if the housing itself is threaded. Does the replacement bolts have threads all the way up the shaft? They are aluminum bolts as I recall. They can easily be drilled out.

 

[DynamicsZ]

Why not remove the other two bolts and see what you are left with. I would think since the head has been flattened the housing should come off. I don't recall if the housing itself is threaded. Does the replacement bolts have threads all the way up the shaft? They are aluminum bolts as I recall. They can easily be drilled out.

The flange is left on that E10. My friend had ground out the head but not the flange part. For now, he has decided to drill it out.

 

[Zeichen311]

Can we use an extractor to drill it in and extract the bolt or take it to a shop? I'm just annoyed he took the shortcut route.

I'm a big fan of letting people pay the price for their mistakes so they actually learn from them. Your friend ignored your advice, barged ahead on the lazy path, and achieved exactly the unwanted result expected. Why keep helping?

An extractor would work just fine, assuming you can get a drill in there. On the other hand, if you refuse to deal with the mess he created, after he pays the bill he might come away more willing to listen to you next time.

(OK, to have a little compassion: in your shoes, I might stick around to help him out of trouble--but only until he showed signs of ignoring advice a second time. )

 

[ede39]

Why not remove the other two bolts and see what you are left with. I would think since the head has been flattened the housing should come off. I don't recall if the housing itself is threaded. Does the replacement bolts have threads all the way up the shaft? They are aluminum bolts as I recall. They can easily be drilled out.

Not a bad idea but it looks like that housing is threaded too

 

[littleredcar]

Why not remove the other two bolts and see what you are left with. I would think since the head has been flattened the housing should come off. I don't recall if the housing itself is threaded. Does the replacement bolts have threads all the way up the shaft? They are aluminum bolts as I recall. They can easily be drilled out.

No way the flange could have threads in it. If it did you would never be able to tighten it down.

 

[littleredcar]

Not a bad idea but it looks like that housing is threaded too

View attachment 1076929

Take a look into the flange hole where one of the other bolts has been removed. You won't find threads in the flange regardless of the image above. The 3 threaded holes in the flange picture above must be for some other part to bolt to this housing not for the housing to bolt to the engine. Again, you can't have threads in 2 separate pieces that bolt together. they would never pull together by tightening the bolt.

 

[ede39]

Take a look into the flange hole where one of the other bolts has been removed. You won't find threads in the flange regardless of the image above. The 3 threaded holes in the flange picture above must be for some other part to bolt to this housing not for the housing to bolt to the engine. Again, you can't have threads in 2 separate pieces that bolt together. they would never pull together by tightening the bolt.

Good point

The head of the bolt is on the underside

So if THAT was sheered off you would be able to pull the remainder through bc the threads are in the housing

 

[SKWDMD]

number 1 side is not threaded. Number 2 side is. If you did cut the head off the bolt I would think once the other two screws are removed it should come off. Unless the number 1 side has threads which the prior poster says it doesn’t.

 

[ede39]

View attachment 1076947
number 1 side is not threaded. Number 2 side is. If you did cut the head off the bolt I would think once the other two screws are removed it should come off. Unless the number 1 side has threads which the prior poster says it doesn’t.

No threads on the #1 side so it would pull away cleanly. Murky waters here tho, you risk damaging a cylinder head. Curious why OP's guy grounded down the threads of that bolt in pic 2. post #1 ?