Head bolts

You mention 'second round of torqueing' - AFAIK this model does not require such a process - the book says tighten gradually in sequence with a finish torque of 65-70lb/ft on bolts 1-10, and 40-45 on bolts 11-14 (AKM3621) - on these last 4 you might go with the 25lb/ft given above. If you have tried to do a tightening involving a torque and then some angle tightening that might explain the breakage. Elsewhere Ron relates that LR now specify to lightly oil the bolt threads, rather than use a special sealer/lubricant. I once had to pull a RR head due to it swallowing a carb needle retaining screw, and a rear bolt snapped off flush with the block as I undid it - the stub unscrewed easily once there was no load on it.

So your saying I should tighten all the bolts to the 65-70 ft-lbs in one go but follow the sequence of the bolts tourqe process?
(I'm not exactly sure what angle tightening is could you please explain)
and with the oil on the threads...can this just be motor oil? Or will I need a specific type? Thankyou
 
In view of your location and the possibility of dropping onto a used set of OEM bolts slim, I think you should be fine with what you have and using anti seize as a precaution.
Yes I may have to use these bolts as the place that told me they could get a second hand set of studs seems to now be unable to find any i guess I'll just have to try it with what I've got...might be a monday job once I steel my nerves
 
I think the consensus seems to be to tighten the bolts in stages, in the correct order, and NOT go for full torque in one go. ISTR that the order goes from the middle of the head, outward to the edges, so as to prevent warping. Good luck.
 
As Mrtask says, tighten bolts in sequence above, in stages - say 15,30,45,65 lb/ft for bolts 1-10, and similar for 11-14, but these are much less important than 1-10. I believe that item 16 in the manual page above is wrong - the long bolts are 1,3,5; the mediums are 2,4,6,7,8,9,10; the shorts are 11-14. My earlier comments relate to later versions of the engine where the bolts are tightened to something low (15?) then all tightened 90degrees in sequence, then another 90degrees - IIRC these will be stretch bolts. Some tension wrenches are angle marked and have movable pointers on the end to assist such tightening. Make sure you are reading lb/ft scale if your wrench also has Nm on it. Dont try to hurry - I am self taught and have never had an issue tightening a head, or a had a gasket leak in a head I have fitted. Any engine oil will do for bolts.
 
As Mrtask says, tighten bolts in sequence above, in stages - say 15,30,45,65 lb/ft for bolts 1-10, and similar for 11-14, but these are much less important than 1-10. I believe that item 16 in the manual page above is wrong - the long bolts are 1,3,5; the mediums are 2,4,6,7,8,9,10; the shorts are 11-14. My earlier comments relate to later versions of the engine where the bolts are tightened to something low (15?) then all tightened 90degrees in sequence, then another 90degrees - IIRC these will be stretch bolts. Some tension wrenches are angle marked and have movable pointers on the end to assist such tightening. Make sure you are reading lb/ft scale if your wrench also has Nm on it. Dont try to hurry - I am self taught and have never had an issue tightening a head, or a had a gasket leak in a head I have fitted. Any engine oil will do for bolts.
Thanks for the help again gives me more confidence with all you guys giveing me these instructions I suppose if I did mess up with useing the copper anti seize on the threads them maybe I can reuse the rest of the bolts and just replace the single bolt that I need...oddly I have found a place that sells single bolts of the size I broke...it would be a cheaper option just not sure if it's the right option
 
I suppose it makes sense to thoroughly clean the bolt holes in the block to make certain there are absolutely no remnants of any previous substances in the threads. Compressed air and stiff pipe cleaning brush, rags stuffed in all the cylinders and water ways, I might even have used a great many ear buds and lots of alcohol (not the drinking kind, the cleaning kind) until I was happy. Equally important to be sure the threads on the new bolts are clean, and only the long unthreaded part has a thin coating of something to prevent corrosion with the alloy head.
 
^^^^^ What he said.
Leaving water or oil in a bolt hole can lead to nasty problems. The bolt can 'hydraulic' this means it can bottom out on the substance in the hole, this can lead to the bolt torqueing up to the correct value, but not having the correct clamping force as the bolt has 'bottomed' on the substance in the hole. If you are really unlucky if an outer bolt is affected, the block could split !
 
I do know holes in alloy heads close up dramatically when corrosion sets in. Trying to get Jaguar XK heads off the studs is a real PITA.
My Alfetta gave me all sorts of hell when I had to pull the head off because of that.
I got lucky, it only took a few hours, a friend took 3 days to get his off.
 
As Mrtask says, tighten bolts in sequence above, in stages - say 15,30,45,65 lb/ft for bolts 1-10, and similar for 11-14, but these are much less important than 1-10. I believe that item 16 in the manual page above is wrong - the long bolts are 1,3,5; the mediums are 2,4,6,7,8,9,10; the shorts are 11-14. My earlier comments relate to later versions of the engine where the bolts are tightened to something low (15?) then all tightened 90degrees in sequence, then another 90degrees - IIRC these will be stretch bolts. Some tension wrenches are angle marked and have movable pointers on the end to assist such tightening. Make sure you are reading lb/ft scale if your wrench also has Nm on it. Dont try to hurry - I am self taught and have never had an issue tightening a head, or a had a gasket leak in a head I have fitted. Any engine oil will do for bolts.
Correct, that procedure is for stretch bolts.
For "Normal" bolts, I'd go half the value in the first go, then full value two times, with the exception of the outer row of bolts. They will remain at half torque.
 
Just curious, when referring to 'outer' row of bolts - do you mean the ones numbered 11,12,13,14 in the image above?
Cheers,
Rob.
 
Thanks everyone who helped I managed to get the engine all back together last night it turns out the old torque wrench I was useing was the reason the bolt snapped It wasn't reading correctly and the pressure was super high...I suppose I should have realized that when I was struggling to torque the bolts at 30ftlb thankfully I broke the bolt and not strip the threads in the block
 
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