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View Full Version : how to measure torque on bolts where a rachet torque wrench cannot fit?



iwamaryu
05-13-2008, 03:52 PM
hey guys the title of the thread pretty much says it all. my situation is that i'm rebuilding my engine and there are certain parts that i would want to be torqued correctly(eg. 48nm) like my exhaust manifold to engine. naturaly with the stock manifold you could just attach 14mm socket on to an extender bar on to the torque wrench, but with my after market manifold; i got huge piping that get in the way where i cannot go from above the nuts. which forces me to tighten the nut from the side with a spanner.

So how do i measure torque on a bolt/nut in a situation like this?

iwamaryu
05-13-2008, 04:21 PM
This it what i'm talking about :
http://i65.photobucket.com/albums/h228/iwamaryu/forum/IMG_0048.jpg http://i65.photobucket.com/albums/h228/iwamaryu/forum/IMG_0036.jpg http://i65.photobucket.com/albums/h228/iwamaryu/forum/IMG_0039.jpg

extremeskillz
05-13-2008, 04:26 PM
Love the diagram and i have no idea except to use a flex ratchet adapter (or a couple) to achieve those odd angles.

extremeskillz
05-13-2008, 04:28 PM
Oh its called a swivel joint adapter for ratchet sets.

Gary
05-13-2008, 05:03 PM
Here you go:
http://home.jtan.com/~joe/KIAT/kiat_3.htm
If you can't keep the angle at 90 degree, here are some calculators:
http://www.belknaptools.com/extcalc.asp
http://www.norbar.com/Calculators/TorqueWrenchExtensionCalculator/tabid/70/Default.aspx

iwamaryu
05-14-2008, 07:49 AM
with the calculators are the values you enter in inches? and torque in ft/lb?

Gary
05-14-2008, 08:06 AM
Use the formula
M1/L1 = M2/L2
M1= Torque setting for the torque wrench
L1 = Length of torque wrench
M2 = Torque you need at the bolt/nut
L2 = Total length (from bolt/nut to your hand)
You can use any unit but they have to be consistent.
If you measure length in "inch", you won't get torque in "ft-lb" unless you divide it by 12.

iwamaryu
05-14-2008, 09:31 AM
so if i use mm as a length measurement i use Nm as torque, and if i use inches as length measurement then is torque Ft/lb or in/lbs?

PhillyDRFT
05-14-2008, 12:22 PM
Won't a simple crows foot work for this?

http://www2.tech.purdue.edu/at/courses/aeml/airframeimages/crows%20feet.jpg

Gary
05-14-2008, 04:26 PM
so if i use mm as a length measurement i use Nm as torque, and if i use inches as length measurement then is torque Ft/lb or in/lbs?

For simple calculation, if you use "mm" for length, your torque will be in "Newton-mm". Divide that by 1000, and you will get "Newton-metre". On the other hand, if you use length in "inch", your torque will be in "inch-pounds". Divide that by 12, and you will get "ft-lbs".

Note that torque is measured in "distance x force" (or vice versa), not "distance / force". So, the correct units are "ft-lbs" or "in-lbs", not "Ft/lb" or "in/lbs".

iwamaryu
05-15-2008, 04:27 AM
thanks gary