Author Topic: Moment of Inertia question (Read 5718 times)

bryanbryan89x · « **on:** September 22, 2006, 01:55:43 pm »

Does anyone know the torque procedure for 11mm stretch bolts? That @$%#$^#$^ hayes only lists it for the 12mm. Since it is a mechanical head i am using a fiber gasket.

burn_your_money · « **Reply #1 on:** September 22, 2006, 02:39:48 pm »

from my bentley
"on engines with hexagon-socket socket-head cylinder head bolts - as originally installed until mid 1981 - torque the head bolts to 50Nm (37 FT. LB) in the sequence given in fig. 5-15. Go over the sequence a second time, torquing the bolts to 70 Nm (52 Ft. lb.) then a third time, torquing the bolts to 90 Nm(66 Ft lbs.)

warm engine until the oil temperature is 50 C (122F) or above, and then stop the engine.

On engines with hexagon-socket socket-head cylinder head bolts, do not loosen any bolt; but torque each bolt to 90Nm (66ft lb) following the 5-15 sequence.

After the car has been dirven 1500 km (1000mi) loosen each cylinder head bolt 30 degrees, then retorque it to 90 Nm (66 ft. lb.s) regardless of whether the engine is hot or cold.

bryanbryan89x · « **Reply #2 on:** September 22, 2006, 03:25:48 pm »

Thanks for the reply but the thing is they are 11mm triple square stretch bolts? do you think I should torque them down the same as the hex???

burn_your_money · « **Reply #3 on:** September 22, 2006, 03:55:34 pm »

Hmm... the bentley never specifies 12mm or 11mm, just "multi-point socket-head"

I'd recommend waiting for someone who knows to chime in :idea:

coke · « **Reply #4 on:** September 22, 2006, 10:42:34 pm »

The procedure burn_your_money posted is for the 11mm headbolts. The stretchbolts never specify to loosen and retorque. I remember distinguishing the procedures by this point. So, you can safely go with what burn_your_money has posted.

fatmobile · « **Reply #5 on:** September 23, 2006, 02:22:48 am »

Sounds like you are using headbolts for a gasser VW.
They are stretch bolts, I wouldn't treat them like regular 11mm diesel hex head headbolts.
I suppose info from a bentley for a VW gasser would be right.
I don't have one handy, not exactly sure what engines they came on.
I'm hoping the 1.8s used the 11mm stretch bolts because I ended up with some ARP headstuds for the 11mm gasser and am hoping to use them on an 11mm diesel block.

burn_your_money · « **Reply #6 on:** September 23, 2006, 06:26:46 am »

I just went and looked for my mk1 bentley but I must have lent it to my friend. I might get it back today though

bryanbryan89x · « **Reply #7 on:** September 23, 2006, 07:27:09 am »

What do you think about this procedure...

50Nm
70Nm
90Nm

warm up

do a 90 degree

drive 1000

do another 90 degree

bryanbryan89x · « **Reply #8 on:** October 09, 2006, 06:48:52 pm »

So I said "the hell with stretch bolts" and bought a set of Raceware head studs in Taylor here. I feel that they worked pretty good, I never knew there was so much to bolts and torquing them. These head studs have a small pitch, and a real fine thread, they also come with an anti-friction coating. Their max toruqe is 50 lbs, but that is actually a lot when all those variables come into play. Also the guy explained to me about the different kinds of torque wrenchs, and which one works best for these bolts, needless to say, since I paid 180 bucks for them I used the right torque wrench (beam style).

saurkraut · « **Reply #9 on:** October 10, 2006, 06:22:23 pm »

Good choice. The other bennifit of the studs is that they thread alot deeper into the block than the stock 11mms. You've also purchased the last head fasteners you'll ever have to buy since head gaskets in VW diesels are a temporary thing (unless you go to the metal head gasket)

I also like how they guide the head onto the block.