snapped head bolts

[ampwhu]

I have 2 snapped head bolts on a head I want to remove.

one is just about 2mm proud of the surface and the other is below, or recessed into the head.

any good tips on getting them out?

[les]

I suppose you could try welding a rod to the top of the studs but not a clean procedure and you don't want any rubbish floating around. Best to remove the head and renew all the studs. How did you manage to wreck two?

[bmcecosse]

The A series uses studs - not bolts to secure the head (with one slight exception) -so is this for something else ?

[IslipMinor]

I don't understand the problem? If a stud has snapped, then surely just undo all the rest and then remove the 2 broken ones?

Can you post a picture of the problem?

[les]

Just re read the post, he wants to remove head anyway, so I don't see the problem either!

[James k]

If they are indeed just below the surface of the head then just remove the head and get them out with couple of nuts tightened together. Soak them in plus gas first if they're stubborn. If though you mean that they're recessed below the bottom of the head, i.e recessed into the block, you'll need a stud extractor.

[ampwhu]

sorry i should have said exhaust manifold studs. they are for my modern car, but they are all the same in principle.

looks like I have around 1mm on one stud and the other is below the surface.

is there a way of removing them without removing the head. I am not doing that.

[edd_barker]

Bummer!

Is it aluminium head? Steel and Alu love to corrode together. I had this taking the head off a 1962 outboard motor.

The one protruding I would try and build up weld on the end until you have a nice big blob to molegrip, the heat will also help.
The sunken one I fear will have to be drilled, tricky with a hand drill let alone at a 90degree angle in a full engine bay. You will need to centre punch the bolt then try and get a tiny pilot hole straight down the centre. There are various extractor bits you can buy that run reverse in a drill, they will have pilot-hole size requirements you need to try and drill in the bolt, then have a go with the extractor bit. Loads of penetrating spray (not WD40). Heat will also help but could be risky if you have a modern engine bay full of wiring and other plastic bits? Hard to say without seeing.

I would google the make/model and 'manifold stud' see what comes up, if it's a common problem there may well be a YouTube video advising, I have been amazed in the past when faced with a specific problem on the van, how many people have also had it and advised how to fix! The forum for your make/model will be a good place to start.

Good luck! I'm sure others will be along to advise also.

E

[oliver90owner]

I would be relying on left handed drills for the second one, not stud/bolt extractors. Nearly all are too hard and very brittle, so may snap off leaving an even bigger problem. Actually I would likely remove the head and do the job with the milling machine, depending on access.

The one with some bolt showing might be a candidate for placing a nut over and filling with weld.

For drilling I would suggest you first bush the manifold hole, then replace over the broken part to get the first pilot hole in straight and central. Good luck if not removing the head.

As you are asking on here it might be better to remove the head and get the job done by an expert, but it may be no great problem even if a larger threaded bolt had to be used as a replacement.

RAB

[biomed32uk]

That is without doubt going to be hell of a job if its well corroded in.

You stand a chance of drilling it out with a decent drill. If you get a drill which is the tapping size of the stud and get it right on centre you can then chase the original threads out with a suitable size tap.

What I would do is get a thick lump of steel (20mm or so) long enough to bolt down securely using some existing studs or suitable fixings.

Drill some suitable holes for clamping it down, and drill a hole using the drill above where it will be on centre with the broken stud. You can make the clamping holes a little bigger to allow some wiggle room to centre it up, you need to be accurate setting it up and then make sure it does not move. The thicker the lump the better, as it will keep the drill square to original hole.

Drill it out and then chase the threads out. Going to a swine to do when its on the car, I really reckon the heads going to have to come off as you stand the best chance with a good drill in decent pedastal drill. Other than that its a spark erosion job, but again the heads going to have come off. Never so easy on a modern car.

Good luck with it, be good to know how you get on.

[john newton]

if you snapped nuts off whilst tightening then they should turn out easily, but if done when loosening,profanitys will ensue. re john

[bmcecosse]

And again it all goes quiet from the OP - which is one reason he is on my 'naughty step'......

[les]

This naughty step Roy, have you got a picture of it, you'll probably have to reduce the file size before it uploads!!

[bmcecosse]

A bit crowded now Les - could probably clear it out a bit if you want a place...... Many of the them have disappeared off the forum now - they usually do. It is of course the 'Friends and Foe' section , although not sure what the 'Friends' benefit is - but the 'Foes' means I don't get troubled by their posts.

[les]

Don't know if I'd get on with the present tenants! I'll try to stop short of qualifying!

[bmcecosse]

Don't think you have any worries there matey!

[les]

Of course it could be the OP has locked himself in the garage, determined to stay there until the studs are out!!

[oliver90owner]

And again it all goes quiet from the OP 

Poster is recorded as 'active' on the 23rd. Maybe just keeping his head down because his meaning of snapped bolts in a head is more usually the holding down fixings - and not bolts but studs, anyway.

Possibly posting for someone to come to his aid? I would do it for him, but to be guaranteed it would be on my milling machine. He would be removing the head. Even more important if the head happens to be an ally one!

Studs should be tight and if manifold studs/bolts are usually breakages due to weakening/hardening due to the heat associated with the exhaust. Adequate clamping force is often achieved by the finer threads at the nut end of the stud.

RAB

[ampwhu]

And again it all goes quiet from the OP - which is one reason he is on my 'naughty step'......

they are head bolts. whether they hold the head down to the block or hold anything else to the head, they are bolts.

[bmcecosse]

But not on a Minor - and this is a Minor forum.......