Sheared head bolt

[andrewLL 19]

Hi, hoping some one can suggest best way forward. I have not been able to start my tractor this year ( K301 engine). It was put away in October 24 working fine, but in June this year it would not start. I have done all the obvious things, cleaned carburettor, checked points, checked valve clearances, put fresh fuel in and flushed out all the old fuel, checked there is a spark.  Using a squirt of easy start didn’t help either.  I have now brought the engine back home to try and sort it, the tractor lives in France, but need to get it done before the spring.

 

The tractor is a 1972 Raider and I assume the engine is original and I have never done anything to it other than service items. I thought it would be sensible to remove the head and see what the inside looked like but unfortunately one of the bolts has sheared. What is the best way of removing the remainder of the bolt?  Because it was tight I used wd40 over a number of days and also heated the engine block with a blow torch.  In the end it broke.  I am reluctant to drill it and screw in an extractor because it is clearly stuck and there is a risk of breaking the  extractor making the situation even worse. What do you all think?

 

Just a thought here, this is a very basic engine, nothing like the Mercedes F1 engine Lando used to win today, would it work without this bolt? It would still have 8 holding the head on.

 

Cheers, Andrew

[702854boy 365]

If you have a welder try putting a washer over the stud and then a nut and put a nice big glob of weld in there and maybe the heat will help you get it out and then you'll also have something to grab onto.

[gwest_ca-(File Mod) 11,820]

With the welder's ground lead on the block any current has to flow through the stud to get to the block when welding a nut to the stud. Usually resistance between the stud and the block will result in heat being created right where you need it.

That is the hottest corner of the head next to the exhaust valve so you need that stud.

[squonk 44,828]

I had the same thing on a small block. That bolt takes all of the exhaust heat. I tried drilling and that bolt was heat hardened. I took it to a friend of mine who mounted the block on his mill and got it drilled straight and put in a helicoil.If your bolt is stuck like mine was you're not going to get it to turn out.

[Handy Don 15,006]

To answer the original question Emphatically YES you need that bolt.

Note that manufacturers do not like spending money unnecessarily. If that bolt wasn’t needed, it simply wouldn’t be there in the first place!

[adsm08 3,791]

WD40 is neither a penetrant, nor a lubricant, and is not at all appropriate to this task.

 

In my experience the idea of welding a washer and nut over it is probably the best bet, short of a machine shop.

[Ed Kennell 43,574]

I have had good results by welding a nut to the broken bolt.     Try to get as much penetration in the bolt as possible.