Clementine's Garage
Clementine the Cat
 
Image of flower
Yellow R4
 
Réparateur d'automobiles

Sheared head bolt

DaveP

Enthusiast
Messages
147
I have one of these, sheared at the end of the shanked section, only discovered when I went to change the engine mount last week, it's the one nearest the bulkhead of the two that hold down the accelerator cable mount. I think the mechanic I used to use broke it when he last removed the manifold and didn't bother telling me, the engine runs really really well and is low mileage (85000kms) so I was wondering if I should try to retrieve it or just wait and see what happens, it's been like this for at least 10000kms if i'm right about when it happened. Is it an engine out or head off job to fix? Or can you just drill and extract it in situ? I'm loth to fix something that's actually working very well.
 
Are we talking manifold to head studs here? If we are i would personally remove the combind inlet and exhaist manifold and give what stud is left exposed a few taps with a hammer and try to unwind it with mole grips. Id this didn't work i would drill it out as there is plenty of room.

Michael
 
No unfortunately it's the actual head bolt, I went to wind it off and it just spun out, I pulled it out and there's a two or three inch shank with a snapped off thread inside the block.
 
Thats head off then i am afriad. drill a 3mm hole in the centre of the broken bolt and try knocking in a long star drive torques piece into it, the shouck may just be enough to unwind it. If not it will need drilling out completely and possibly helicoiling
 
Not what I wanted to hear, I think I'll leave it for the moment and look out for a long extractor set, filled up the hole with wd40 for the time being.
 
Sorry. If it is running ok then just keep an eye on it for now. If the gasket starts to blow Stop Driving.
 
Back
Top