Torque setting for engine bolts please

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julianharty
Posts: 478
Joined: 15 May 2016 16:34
Location: High Wycombe
Location: High Wycombe Area (Bucks)

Torque setting for engine bolts please

Post by julianharty »

I've searched here, and in the blue book & even the Harglo manual. Others have asked this question, however since it's not been answered from what I can tell, I'll ask:

What do you use/recommend for the torque setting for the engine bolts please? And do you use different values for the bolts that go through the engine and those that hold the front engine mounting plate to the downtubes? kg/m or Nm would be ideal.

I've fitted a new set of high-tensile bolts, from Paul, to a 3 1/2. Currently I've used 2.3Kg/m, the same as the upper limit for cylinder head bolts.
harrymuffin
Posts: 292
Joined: 07 Apr 2014 16:06
Location: west midlands

Re: Torque setting for engine bolts please

Post by harrymuffin »

Find attached the recommended torque settings for different sizes of bolts and their tensile strengths. You could of coarse ignore the recommendations and use what a chap from Bedfordshire uses, an air impact wrench set to maximum. Not sure if the attachment is going to load, being told either PDF not allowed or file too big.
/Users/nigelprice/Desktop/Torque settings.rtfd
julianharty
Posts: 478
Joined: 15 May 2016 16:34
Location: High Wycombe
Location: High Wycombe Area (Bucks)

Re: Torque setting for engine bolts please

Post by julianharty »

Harry, the attachment doesn't seem to have loaded. Could you copy+paste the contents of the file here? or if the contents are too much to be pasted in full, then whatever you can usefully extract from the document?

You're welcome to email the file to me julianharty@gmail.com and I'll have a go at pasting the contents here.

Thank you.
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Ming
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Joined: 01 Aug 2014 16:32
Location: France
Location: Central France

Re: Torque setting for engine bolts please

Post by Ming »

You could look for standard torque recommendations on line, such as http://www.wtools.com.tw/STANDARD-BOLT- ... RQUE.shtml
Or as suggested, you could use an impact wrench that you are used to setting for the required torque.
I use the old method of tightening until the veins on my forehead stand out... :shock:
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Torque setting for engine bolts please

Post by MickeyMoto »

F#@£&%g Tight is the usual answer. I always thought that was what ft meant in the torque figure! I have gone to 35lbft, but not sure if too tight. Do not forget the thicker washers...
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72degrees
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Joined: 31 Aug 2007 21:24
Location: West Midlands

Re: Torque setting for engine bolts please

Post by 72degrees »

MickeyMoto wrote:Do not forget the thicker washers...
*THIS*

On a 350 in a 250 frame (only three front mounting bolts) a drop of Loctite is also a good idea.
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