[araa123]

Hi, I have a Rover 416si, 16 valve, 'P' reg.
The fault - the head gasket failed, which I have now replaced, but when it came to tighten the head bolts (stretch bolts), one snapped, approx 1 inch off the end, about half way up the thread. Is it possible to take the piece left in, out through oil sump? or does anyone have any better ideas? Thanks

[Rolebama]

If one snapped, I would consider them all suspect, and get a new set. (I thought they were one-time use only, but am sure Hometune or someone will set the record straight on that.) As to removing the broken bit, to be honest, I would dismantle and start again.

[araa123]

Yeah, they are one time use only, it was a new set, which is really annoying. The length of the bolts are about 40cm long, so it's a long way down to take out through the top. Maybe i'm wrong? Thanks for the reply.

[Hometune]

The head bolts CAN be re-used but there are conditions. You must be able to screw them all the way down by hand then measure from the top of the block to the underside of the flange on the bolt. The maximum length is 97mm. BUT:
I imagine you have had the head skimmed/machined before refitting. If so this means the head is thinner so you are effectively making the bolts longer. The bolt them 'bottoms' in the sump and this leads to people thinking the head is correctly tightened down. A few days later and the head starts leaking again.
I always remove the bottom thread of the bolts on a bench grinder if the head has been skimmed. This ensures no 'bottoming' or under tightening.
If you remove the sump you should be able to retrieve the broken part.
I would advise you fit another head gasket as the failed tightening will have compressed it. Also, make sure there is no oil or water in the bolt holes which can cause hydraulic locking.
The correct tightening is:
1. 20nm
2. 180 degrees
3. 180 degrees

[bandit600]

If you remove all the head bolts, and then the sump, you will see an aluminium bearing ladder. This is what the headbolts screw into and it can be removed so you can rectify the fault.
You'll need another headgasket now though.

[araa123]

Thanks all for the help. Got the sump off, and saw there was enough thread through to get a stud removal tool on, so was able to take it out through the underside, without having to disturb the other bolts. I've got the haynes manual, but it wasn't very clear.