Author Topic: Re-torque head bolts?  (Read 8857 times)

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Vince

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Reply #15 on: January 25, 2009, 04:52:45 pm
     Back to re-torquing. Some things I forgot to mention, Torgue in at least three stages.  Don't go to full torque on the first pass. On the Enfield cylinder head start at 8#, then 16, then 24. Go in a star pattern. don't go around in a circle. If you have the time and patience four passes at 6,12,18,24 would be better. Wait 1/2 hour and re-torque to 24 again. Let sit over night, then torque at 24# again. now proceed with the rest of the assembly. The rocker caps are done the same way -an X or star pattern in at least 3 stages with a 1/2 hour wait for a re-torque. you won't need to wait over night for another session.


clamp

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Reply #16 on: January 26, 2009, 12:53:14 am
Torque is simply measuring the power/force to turn the nut. It does not take into consideration friction for example.

     It is paramount importance therefore that the threads are cleaned and oiled with washers all of the same.

     Some cars today(my Mazda diesel) requires that you torque to 20lbs or metric equivelent and then after marking with paint, turn 180 degrees disregarding torque and then 180 degrees again.

     BUT on some engines the bolts are designed to be stretched and hold the head down hot or cold like an elastic band.

       Jag big end bolts are wasted and are similar.  If the exceed a certain length they are to be discarded.

     Any torquing should be in stages 3 times minimal
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UncleErnie

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Reply #17 on: January 26, 2009, 01:35:45 am
May I assume you both are talking about initial assembly?

I'm merely talking about checking torque prior to checking/adjusting rockers. 
As a BMW apprentice, I was taught to back the bolt off a quarter to half turn, and then re-tighten to spec.
HOWEVER- if RE uses the kind made to stretch, then I wouldn't do that.

Came in from a ride today and found a nut at the right-side cylinder base very loose.  I fear re-torquing all head bolts may be a good idea.  I was going to wait until 2000 miles, but maybe i should do it sooner.  ?
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Vince

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Reply #18 on: January 26, 2009, 03:02:12 pm
    Do it now!


UncleErnie

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Reply #19 on: January 26, 2009, 11:34:20 pm
10-4!
Thanks ~
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UncleErnie

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Reply #20 on: January 29, 2009, 05:34:41 pm
For the crowd that has been biting their nails-
One nut was VERY loose and all whee checked to 24 lbs.
Valves were confusing- One place in the manual says to set them to zero tolerance, but there are pictures of a hand using a feeler guage and then I found a spot that says to set them to .01- so that's what I did.  The pushrods spun quite freely, but I feel good aout the setting, so I went with that.

Ordered some new rocker cover gaskets and plan to install them next time with something less rock-like (if you know what I mean). 
This is interesting getting to know this particular bike. It definitely has it's own eccentricities.
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