Broken bolts...

[DaveEFI]

Not really cooling system related, but here goes.

I've removed the dead water pump - and of course the inevitable happened.
Three of the 1/4" bolts sheared. The two at the top left quite long 'stumps' so after a kettle of boiling water was poured over them, out they came using mole grips.

The other is more of a problem. At the bottom and close to the crank pulley, access is more restricted. It also goes into a blind thread. And has only about 1/4" of a 'stump' left. Boiling water doesn't seem to heat it up by much - too much mass round it?

I've stopped for the day as it's raining and getting dark.

So any tips how to remove it? Next thing I was going to try was a hot air gun on it. Not too keen on using a blowlamp there.

I suppose at the end of the day it will mean removing the front cover, drilling and helicoiling. At least I have the correct helicoil set.

Why do these things always happen in the winter? It's been fine all spring and summer.

[Alley Kat]

Had similar on my Landy, couple snapped bolts with little stumps left. I welded on a nut, got it good and hot. Left it to cool - heat probs helped break it free - then wound it out.
Although the block's one massive heat sink the weld got it properly hot.

Danger is if the nut turns off, if either it wasn't melted well onto the stump, or the bolt was stuck fast, it might snap flush.

[gelmonkey]

Dave
Could you get a small butane powered soldering iron to the bolt?
This could be used to locally heat the bolt and surrounding area.
Heat and then squirt with wd and then heat again.
This may well release the grip on the thread.

If that is a no go could you get a small stud extractor on to the stub and remove that way?

Cheers
Paul

[Ian Anderson]

Hit the end with a hammer
It will also cause a shock loading and may break the "seal" / Corrosion

Ian

If that does not work get a bigger hammer - or some penetrating oil (not WD40 - proper stuff)

[ChrisJC]

In my experience, welding something to the remnants is the best option.

Chris.

[unstable load]

Put a nut over the stub and weld it onto the stub.
As it cools it shrinks and breaks free, it will screw out easily, sometimes even by hand.

[DaveEFI]

With some trepidation I dug out the MIG - which I've been trying with gasless wire, even although it's a gas only one. I'm pretty useless at welding - and had to work near blind, given the location.
But it worked - although it was still so tight I thought I'd shear it off flush.

So thanks, guys.

The weld looked pretty good. Perhaps I should do them all blind?

[ChrisJC]

Good result - well done!

Chris.