Apprentice Question or Torquing

[AarhusTr6]

Hi

The inlet manifold, the top three nuts, I think they need torquing to about 20lb . . but how do I do that if I cannot get a socket fully onto  the nut?

Richard

 

 

Edited June 1, 2021 by AarhusTr6

[RogerH]

Hi Richard,

My bodging answer is do you need to torque it at all?. Using a ring spanner etc you can feel how tight a torqued nut is on the manifold - do this to the difficult ones.

The engineering answer is -

put the ring spanner on the nut

Attach the torque wrench  to the ring spanner  with a nut& bolt - this will give a lower reading to the torque setting.

I'm not sure if this is correct - but if the torque wrench is 12" long and the reading is 20lb.ft then adding a 12" ring spanner should bring the value down to 10lbs.ft

 

Roger

 

 

[RobH]

If a torque wrench will not fit, you can use an ordinary ring spanner, a spring-balance and a bit of arithmetic. 

There are 'crows foot' ends which will fit a torque wrench, but they change the set figure a bit and are often too wide where there isn't much clearance.

[John Morrison]

Richard,

years ago, when we were looking after old cars on a tight budget, and with little or no

proper tools, we had a rule of thumb on torquing down nuts.

Basically, take a ring spanner, estimate the length (30cm is a good rule), and if you pull the spanner with one finger, we called that 10ft lbs, two fingers we called 20 ft lbs.

With the manifold nut syou are looking at here, I would use this rule.

John.

[AarhusTr6]

12 minutes ago, RogerH said:

Hi Richard,

My bodging answer is do you need to torque it at all?. Using a ring spanner etc you can feel how tight a torqued nut is on the manifold - do this to the difficult ones.

The engineering answer is -

put the ring spanner on the nut

Attach the torque wrench  to the ring spanner  with a nut& bolt - this will give a lower reading to the torque setting.

I'm not sure if this is correct - but if the torque wrench is 12" long and the reading is 20lb.ft then adding a 12" ring spanner should bring the value down to 10lbs.ft

 

Roger

 

 

Hi Roger

I learn something every day with this forum and car, thanks for the education!

Richard

[AarhusTr6]

13 minutes ago, John Morrison said:

Richard,

years ago, when we were looking after old cars on a tight budget, and with little or no

proper tools, we had a rule of thumb on torquing down nuts.

Basically, take a ring spanner, estimate the length (30cm is a good rule), and if you pull the spanner with one finger, we called that 10ft lbs, two fingers we called 20 ft lbs.

With the manifold nut syou are looking at here, I would use this rule.

John.

Wonderful!  here is a picture of my hand ;-)

 

 

Edited June 1, 2021 by AarhusTr6

[BlueTR3A-5EKT]

21 minutes ago, John Morrison said:

Richard,

years ago, when we were looking after old cars on a tight budget, and with little or no

proper tools, we had a rule of thumb on torquing down nuts.

Basically, take a ring spanner, estimate the length (30cm is a good rule), and if you pull the spanner with one finger, we called that 10ft lbs, two fingers we called 20 ft lbs.

With the manifold nut syou are looking at here, I would use this rule.

John.

This spanner length thing was addressed by Rolls Royce Aero.

 All the spanner’s they produced that I have seen are stubby little things that you could never apply much force/torque to.  This meant a torque wrench was required in all instances to secure a fastener correctly.

Peter W

[Bfg]

If you think it is important . .  

..put a ring spanner on the nut and hook a spring balance to the other end - to pull at 90 degrees to the spanner. 

Force x distance = torque,  so if your ring spanner is 6" long then you'll want 40 lb force reading on the spring balance to achieve 20 ft-lb of torque on the nut.  

Of course a spring balance could be substituted with a load cell or else even a pair of bathroom scales (pushing at 90 deg to the end of the spanner).

[boxofbits]

A lot also depends on the condition of the threads, and in that regard the correct clamping force might be even less likely achieved with a torque wrench. You have to develop a feel for how tight a nut should be, and by doing this you’ll also get to know whether it’s binding on the thread or actually tightened on the components which a torque wrench will not tell you, but don’t overthink it.

Kevin

Edited June 1, 2021 by boxofbits

[ed_h]

20 ft-lb = 2 elbow clicks.

Ed

[Motorsport Mickey]

15-20 lbs ft ...The same amount I use for the tin sump gasket or the tin rocker cover. Ring spanner and by hand.
Try it first on a similar size nut and bolt in a vice, you’ll soon get a feel for the effort to give approx the torque needed within a couple of lbs ft. Close enough for these lowly torque figures.

Oohh ...don’t forget to say “ click..click” when you think you’ve got it up to torque... it’s essential.

Mick Richards

[PodOne]

Always taught by my father in law who worked on anything from giant marine engines to Lucas pumps for HGV's in later life to just hold the spanner closer to the nut/bolt to get less torque as I was a b.....r for shearing things! Not often he reached for a torque wrench he just seemed to know when enough was enough but then I suppose that what comes with a life times experience.

Andy

[Andy Moltu]

There are 3 settings for tightening by hand.

Gentle - hold spanner in hand with hand near to the ring.  Alloy threads or1/4 unf.

Moderate - as above but using a good degree of force. This is what you want here. (Otherwise know as 2 clicks of the elbow)

Gorilla tight -full force applied with hand away from the ring. Rarely required other than cylinder head bolts.

A torque wrench is to enable even pressure or to prevent use of he Gorilla tight setting.

[stuart]

10 hours ago, Andy Moltu said:

There are 3 settings for tightening by hand.

Gentle - hold spanner in hand with hand near to the ring.  Alloy threads or1/4 unf.

Moderate - as above but using a good degree of force. This is what you want here. (Otherwise know as 2 clicks of the elbow)

Gorilla tight -full force applied with hand away from the ring. Rarely required other than cylinder head bolts.

A torque wrench is to enable even pressure or to prevent use of he Gorilla tight setting.

There is a 4th one often used more to undo bolts where you really need a decent sized socket drive but can get it in there and thats the combination spanner and fit the ring end on the nut and another similar length spanner ring end engaged on the open end of the first, doubles the force and can get you out of trouble. Not recommended for those of you who dont understand the consequences

Stuart.

[RogerH]

17 minutes ago, stuart said:

There is a 4th one often used more to undo bolts where you really need a decent sized socket drive but can get it in there and thats the combination spanner and fit the ring end on the nut and another similar length spanner ring end engaged on the open end of the first, doubles the force and can get you out of trouble. Not recommended for those of you who don't understand the consequences

Stuart.

+1   -  ouch 

[John McCormack]

16 minutes ago, stuart said:

There is a 4th one often used more to undo bolts where you really need a decent sized socket drive but can get it in there and thats the combination spanner and fit the ring end on the nut and another similar length spanner ring end engaged on the open end of the first, doubles the force and can get you out of trouble. Not recommended for those of you who dont understand the consequences

Stuart.

I often use this method for undoing bolts/nuts. 

For the manifold nuts my approach for 50 years has been tighten the buggers up hard. You won't strip or distort them and it doesn't matter as long as it is good and tight.

I await the proper mechanics telling me off.

[Charlie D]

There is a well-known saying:

“There is more than one way to skin a cat.”

 

After reading this thread I’m inclined to believe it should be re-written as:

“There is more than one way to skin your knuckles.”

 

(And I’ve tried them all…)

 

Charlie.

[john.r.davies]

Richard Aarhus,

There is an accessory known as a "crowfoot" spanner, always open-ended but some straight, some hex, some 12-point.   Thay are desisgned to be used with a ratchet or torque wrench, in confined spaces.

 

Buy one to fit your torque wrench - but you may have to buy one of those that registers low torques to deal with this.  Most general purpose TWs start about 50lbs-ft.

 

In general, "hand tight" is about 10lbs-ft, and is literal, the torque you can apply using only the hand and forarm muscles.     Bring the shoulder into play and you can double that, to the 20 you want.  This is not a critical  torque!    We are not dealing with Rolls Royces here!!

JOhn

[Hamish]

1 hour ago, john.r.davies said:

 

 This is not a critical  torque!    We are not dealing with Rolls Royces here!!

JOhn

and Rolls Royces were not that precision - they were hand made you know !!

and yes they did drive round cheshire with a bloke in the  boot to try and id where the rattles came from if needs be.

 

a famous saying was the only thing you could hear in a Rolls was the ticking of the clock- and when they moved to an electronic analogue clock the picked one with an extra loud tick.