Head Bolt Torque Sequence
Created by: Rosebud
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The HBOL is full of innaccuracies and misinformation.
The BLMC orange book states that the 10 3/8" nuts are torqued to 42lbft and the single 5/16" bolt to 25 lbft.
I tend to believe the factory manual more than the HBOL.
The factory correct sequence is to remove the bolt and the tenth nut (by the heater takeoff) before unbolting the normal nine in the correct centre-outwards circle.
Refitting requires the normal nine to be progressively tightened in the correct sequence and torqued to 42lbft before fitting and torquing the tenth nut and finally the bolt.
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Hmm… lots of caveats. What to do?
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Quote:
Originally Posted by Rosebud
I have an 11 bolt A series head. Haynes sez: remove bolts 10 & 11 first, then remove the remaining bolts following the circular sequence in reverse order as shown in the manual. My question is, when reinstalling the head, do I begin by tightening bolts 10 & 11 first and then follow the standard sequence, Or do I simply include bolts 10 & 11 in the sequence?
Cheers, Ian
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Quote:
Originally Posted by CooperTune
On Cooper S 11 fastener cyl. heads the front fastener is a special 5/16 bolt. That fastener takes 25 ft. lbs.
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I'm thinking that last post may be in question. On Cooper S 11 fastener cyl. heads the front fastener is a special 5/16 bolt. That fastener takes 25 ft. lbs. The rear is a normal 3/8 stud and takes the same torque as the other 9 studs. Not uncommon to see a 3/8 stud installed it that forward location. As the threaded hole in the forward location passes though the water pump housing area of the block there is a chance of cracking the block. Just something else to think about. Steve (CTR)
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#'s 10 & 11 are torqued to 25 #/ft, not the 40-45 as the others.
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According to what I see, the two end bolts are first to remove, last to install.
//www.reizendemoke.be/techniek/manual/engine/2.htm
Don't forget to tighten the fasteners in "steps" to the specified torque. I'm sure you already know to adjust the valves when you are done.
//www.reizendemoke.be/techniek/manual/engine/2.htm
Don't forget to tighten the fasteners in "steps" to the specified torque. I'm sure you already know to adjust the valves when you are done.
Doug L.
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They are added to the end of the tightening sequence, number 10 is by the thermostat, 11 at the clutch end of the head. They are the first to be loosed in reverse order.
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I have an 11 bolt A series head. Haynes sez: remove bolts 10 & 11 first, then remove the remaining bolts following the circular sequence in reverse order as shown in the manual. My question is, when reinstalling the head, do I begin by tightening bolts 10 & 11 first and then follow the standard sequence, Or do I simply include bolts 10 & 11 in the sequence?