When stripping down the twin port engine for our beetle I managed to snap one of the studs off for the exhaust manifold (heat exchanger side of heads). Decided I could fix the problem with a stud remover kit, didnt read the instructions properly and managed to snap the bit in the bolt, then tried to drill it out and drilled off centre completely stuffing it now i have a hole in the wrong spot and have pretty much stuffed the head. Is it possible to buy another head and fit it or am i best to find a matching pair of heads?
I can't comment of the machining or replacing of heads. But I have removed a broken exhaust stud in the past by welding a nut onto the remains.
Because the heads are alloy the metal will not stick to it.
Get a nut that the hole is the same size or slightly bigger than the stud, place it over the studs remains. Then you weld down through the hole and
onto the stud. Make sure you strike the arc onto the stud and not the nut so you get good penetration. Otherwise you'll just end up with a nut full
of weld and no meat holding it to the stud, it'll just twist off.
I hope this helps or is at least something for you to try on the next one you have.
Smiley
In terms of a stock engine it really doesn't matter whether your heads match or not, so you can buy either just another one or a pair and put them on. Shouldn't be too expensive.
i am sure you could get the head fixed alot cheaper than replacing it.
Thanks for the info, unfortuately the stud broke off flush with the head so cant get anything on there which is a pain. Could the hole (that super mechanic me drill into the head off square) be tig welded up and then redrill and taped to suit? That the only way I can think of fixing it. Is there a difference between 1300 and 1600 heads if so is there an easy way to tell the difference?
There are two main reasons for a stud (or bolt) to break off.
The first (and least often seen) scenario is the stud failing in some way (sheared off or some other trauma).
If you use a stud remover kit, the drag on the thread is negligible and will come out easily. Often they can be removed with a small hammer and a
sharp punch.
I have removed studs broken off in holes that were not blind and as the drill bit into the stud it wound it clean out the other side.
The most often seen scenario is when the threads are frozen together. There are many reasons for this (Rust, Galvanic corrosion etc.).
This is the bad boy folks.
The truth is that if you broke the stud off undoing it you will almost certainly break your stud remover trying to remove it!
Sure, Give it a go BUT stop before you break it. A professional will charge you less at this stage
can you get an drill onto it if you can drill a hole and use an easy out they screw in the oppirsite
way to a stud anit clock wise
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The reason the drill went off centre is because the broken stud remover is harder than your drill bit and it is not going to touch it. The bit just
slides to one side.
Once the stud remover is broken off in there I would recommend seeking professional help. There are many places that offer such services and many
offer
a mobile service and will come to you.
Your head may be able to be saved. The broken stud remover needs to be ground out and a larger hole is drilled and tapped. A thread repair (helicoil)
probably
won't work so a larger bolt can be screwed in, cut off flush, and a new hole drilled and tapped.
By the time you have paid for this you have probably spent enough to buy another secondhand head.