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+--- Thread: head bolt torque and block (/showthread.php?tid=7900)
RE: head bolt torque and block - Reckless Rat - 12-08-2022
No need, you're right. The HT lead comes out of either end of the coil and goes to both cylinders so the plugs fire together (sort of) There's no distributor.
RE: head bolt torque and block - Ruairidh Dunford - 12-08-2022
Sorry, was my humour at play.
RE: head bolt torque and block - Alan - 12-08-2022
And mine
RE: head bolt torque and block - bystander - 12-08-2022
(12-08-2022, 12:49 PM)Henry Harris Wrote: Austin Service Journal, January, 1939
Is it possible a later Volume of the Service Journals may have amended or corrected these figures?
RE: head bolt torque and block - Reckless Rat - 12-08-2022
Got me.
RE: head bolt torque and block - Henry Harris - 12-08-2022
Back to cylinder head studs....,
One has to wonder what the specification of the factory studs was.
However, from the Reliant workshop manual. (Side valve engine)
"Cylinder head nuts 25 lb feet (34 Nm)
Big end bearing bolts 21 lb feet (28.6 Nm) "
RE: head bolt torque and block - andrew34ruby - 12-08-2022
Don't think I'll rush out and buy a torque wrench. Never needed one so far.
RE: head bolt torque and block - JoeRowing - 12-08-2022
Clearly there are several camps. I own 4 torque wrenches...
I have a reasonably well calibrated elbow having been doing this stuff from the age of 4 but there is no substitute for a torque wrench if you want to push the envelope of possibilities.
On dad's racing engines we did a lot of destructive testing and assembly-disassembly to see what we could get away with. One of the things that was done was helicoiling all 10 studs right from the off.
The findings on non helicoiled were simmer to the higher end torques above.
On my ruby I went with the torque wrench and the manual. I don't know the provenance of the studs or the material they're anchored into so discretion is the better part here.
RE: head bolt torque and block - Steve Jones - 12-08-2022
What a lot of talk (torque!!). I've used the same process for nearly 40 years on touring, trials and racing engines and it's always worked. Use a Torque Wrench and start with 5 lb ft. Then 10 lb ft. Follow with 15 lb ft. Finish with 19 lb ft. Leave overnight. Tighten again to 20 lb ft. Run the engine as normal and tighten back to 20 lb ft after each run until it tightens no further. If an alloy head, do the process after each run cold, if a CI head, warm.
Steve
RE: head bolt torque and block - John H - 12-08-2022
I recently did the head gasket on our chummy and more-or-less did what Steve describes above. FWIW, it took four heat cycles before the nuts stopped moving, so it seems these 'ere modern gaskets compact down quite a bit! I finally did them to 20 lb/ft, using a decent Britool 4 to 24 lb torque wrench. You need a small low range one like this to be accurate at these torque settings, i.e. big torque wrenches are not accurate at low torques. If that makes sense!