Author Topic: Rocker box stud torque settings  (Read 1575 times)

Offline gold33

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Rocker box stud torque settings
« on: 04.09. 2010 12:34 »
G'Day all,

Have been having a great time running my machine in, too much rain this weekend for a ride so I've pulled the tank off to find my oil leaks.
The (hopefully only one) leak is coming from the base of the rocker cover, 3 separate gaskets and all of them leaking.

What order should I re-tighten the studs in after replacing gaskets? and what torque setting is recommended?
'52 Plunger

Online BSA_54A10

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Re: Rocker box stud torque settings
« Reply #1 on: 04.09. 2010 13:42 »
Do it up as you would a head.
Start from the middle and work towards the ends in a criss cross pattern.
Torque is pretty arbitary.
Any more than 35 ft /lbs and you will strip the threads some some where around 15 would be good enouhg.
More important is to try and get them consistant.
Consistency is much more important than numerancy ( sort of like argueing with a 5 year old)
Bike Beesa

Online RichardL

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Re: Rocker box stud torque settings
« Reply #2 on: 04.09. 2010 14:52 »

Moreover, you can't really throw a torque wrench on the stud nuts. Yes, you could use a fish scale on the end of spanner and apply some maths, but that seems overkill. I know BSA_54A10 doesn't spout out numbers without a lot background knowledge, so, I suppose 35 ft/lbs probabaly does represent stripout, but that's the value I and others here use for head bolts. As he implies, stay well clear of that. I think most of us, and probrobaly yourself, have developed some touch for how much ooomph to apply to various thread diameters and pitches. You can develop consistency by using the strength available at the tips of various fingers, or combinations thereof. OK, I suppose this is preaching to the choir. Bye.

Richard L.
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Online chaterlea25

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Re: Rocker box stud torque settings
« Reply #3 on: 04.09. 2010 22:13 »
HI All,
The rocker box bolts are 5/16 x 26 tpi , the same as the big end bolts which are torqed to 22ft/lbs
I would think this is too tight for the rockerbox bolts
hand tight with a short ring spanner will be fine
the mating surfaces on the rockerbox head joint are very narrow, overtightening will cut into the gasket and squeez it out of the joint!!!
In my ?0.02 opinion the gaskets supplied in sets are only fair in quality and fit
I prefer to make my own most of the time from "klingerite" or similar material,
which reminds me I must go and buy some more sheets of it ;)
John O R
1961 Super Rocket
1963 RGS (ongoing)

Offline dpaddock

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Re: Rocker box stud torque settings
« Reply #4 on: 05.09. 2010 02:16 »
 12 ft lb, and use a bit of Hylomar or Permarex Ultra on the gasket faying surfaces.

'57 Spitfire