Broke cylinder head stud - Need ideas

Broke cylinder head stud - Need ideas

Author
Discussion

Postve

Original Poster:

26 posts

53 months

Monday 13th January 2020
quotequote all
I heard a slight wheezing noise after re-torquing the cylinder head, popped the hood, and noticed that the bolt that secures the coil #8 was loose and can see bubbling - water - dripping out. To my horror, the stud had snapped off in the block - this sucks!!

That is not the worst of it, I tried a "tap screw', after drilling etc and surprise that breaks off in the block and embedded in the stud - I think I am screwed.

Suggestions as looking at a diamond tipped drill bit + the screw extractor (should have used this first) heat that surrounding area and pray to the mini gods that it unravels.

Please if any thoughts more than welcome@@

Here's a picture of what I screwed up!!!!


rufusruffcutt

1,539 posts

205 months

Tuesday 14th January 2020
quotequote all
Looks like a challenge!!

Do you have access to a welder? Put a large thick washer on the block over the stud hole and try to fill the hole with weld, grind the weld back so you can then weld a nut to the thick washer, and then pray that the whole lot turns and unscrews.
Obviously care should be taken to protect the block and bores from welding and grinding!
The tricky bit is not welding the washer to the block, but to the remaining stud / stud remover.
And may also depend on what type of metal the stud remover was made from, as to whether you can weld to it.

Anyone else got any ideas?

liner33

10,690 posts

202 months

Tuesday 14th January 2020
quotequote all
Take it to a garage or engineering shop . Its bread and butter stuff for them and they could drill it or as said weld a nut on . It will be cheaper than having to repair it should you screw it up .

Postve

Original Poster:

26 posts

53 months

Tuesday 14th January 2020
quotequote all
Both you fellows are awesome and thank you for the response.

The metal on the tap screw is "hardened" - with good reason and for my worst case scenario (lol) - so nothing but a "carbide" drill bit I'll get this thing out if at all. I spoke to a seasoned mobile machinest today and he recommended - as did lliner - that be extremely careful as I am wayyyy out of my depth on this type of repair and already messed it up the first time around. He proposed as follows:

- Take a carbide tipped centre punch and try and remove as much of the bolt as possible and limit damage to the threads;

- He can then come over and take a good look and see if it can be reamed out - block still in engine - and re-threaded (this is where the welding suggestion may come in but at the hands of an expert and certainly not me..;

- If the above does not work, pull the friggin block - I really want to avoid this - and take back to his shop to have it machined - on the plus side I could add the "lightened" fly wheel at that time - food for thought.


rufusruffcutt - I would not even attempt welding as again I am quickly realizing my limits when it comes to my little mini. I can do most things but leave the truly mechanical expertise stuff to the big boys!!

Plan for the rest of the week - centre punch the crap out of it and see if it moves - after heating it up a bit - ya never know the mini gods may shine on my backside yet - lol

Any other thoughts would be more than welcomed to hear..Boy, a real challenge with this one I tell ya!!

Edited by Postve on Tuesday 14th January 18:16

elanfan

5,520 posts

227 months

Tuesday 14th January 2020
quotequote all
I’d suggest you dont waste any more time on it. Bite the bullet, take it out and to an engineering shop. That way you know it’ll get done. Doubt it’ll cost test much.

Postve

Original Poster:

26 posts

53 months

Tuesday 14th January 2020
quotequote all
You are probably correct sir!!

Will take that advise as I ponder my options during the week.

Postve

Original Poster:

26 posts

53 months

Tuesday 14th January 2020
quotequote all
Another question;

Regarding the studs - I ordered short and small and I assume that the front of the head takes the long and back takes the short. Reason I ask is the one that broke was position #8 - from my research - and was sized differently than the remaining for along the front?

I did not look carefully enough - rookie here - and now notice that the guy who installed the old head had various sizes??

Here's my new CST head prior to the stud breaking. (The one next to the heat tap snapped in the blockfrown


Lotobear

6,344 posts

128 months

Wednesday 15th January 2020
quotequote all
That pic appears broadly correct - the longer ones need to pass through the rocker pedestals at the rear and the short ones go to the front.

Front left needs to be longer however as it also acts as a pick up for the coil bracket.

Edited by Lotobear on Wednesday 15th January 12:37

Postve

Original Poster:

26 posts

53 months

Wednesday 15th January 2020
quotequote all
Thx Lotobear, confirmed and now back to planning the engine block pull - first time so will be a learning exercise!!

Postve

Original Poster:

26 posts

53 months

Sunday 26th January 2020
quotequote all
Just waiting for a nice stretch of weather and shipping mini to my old mechanic, he is going to try and weld it and remove - wish me luck !!

Postve

Original Poster:

26 posts

53 months

Wednesday 29th January 2020
quotequote all
Postve said:
Just waiting for a nice stretch of weather and shipping mini to my old mechanic, he is going to try and weld it and remove - wish me luck !!
Okay, shipped down yesterday to the mechanic and waiting for him to hopefully work some magic and get this broken stud removed..

Olas

911 posts

57 months

Wednesday 29th January 2020
quotequote all
If he can’t get the stud out you have the perfect excuse to build up an 8 port 1380 - start looking for parts now!

Postve

Original Poster:

26 posts

53 months

Wednesday 29th January 2020
quotequote all
Hummm, you are a mind reader tongue out

Postve

Original Poster:

26 posts

53 months

Saturday 1st February 2020
quotequote all
Got it!!!


liner33

10,690 posts

202 months

Sunday 2nd February 2020
quotequote all
Postve said:
Got it!!!

Easy when you have the kit and know-ho . Good result !

rufusruffcutt

1,539 posts

205 months

Monday 3rd February 2020
quotequote all
woohoo

cml24

1,413 posts

147 months

Saturday 15th February 2020
quotequote all
Welding a nut on has always worked for me as well. Not head studs but others on minis.

I've always found though, that something that was tight enough to snap, after the heat of welding is finger tight!

Glad it's out!

Postve

Original Poster:

26 posts

53 months

Saturday 15th February 2020
quotequote all
Yes I am grateful that it did come out and I bought myself a couple lottery tickets!