torque settings??? (HELP)

The engine oil-sump drain-plug has a copper washer, so just torque it by about a 1/4 turn and it should be fine. The drain plugs do not require precise torque settings, just use your judgment and not too tight to damage any housings or strip threads. About 25-35Nm should be OK for 17mm plugs and about 40-50Nm for 19mm plugs.

Hello, Antionio,

I think your torque setting seem about right. In anycase the actual torque acheived on the plugs depends on many things, like for example if there is oil on the threads. It is not an exact science.

Usually the differential plugs have a conical thread and I found that if you wrap PTFE tape (plumber's thread-sealing tape) around the threads, then it helps to seal with much less torque and it makes the plugs easier to remove the next time.

I bought a new eninge sump plug about 6-months ago from a dealer and it was the same as the one before, requiring a copper washer. This one you were given must be a new thing. As far as I know the oil-sump plugs have long, parallel threads and so require the washer to seal. but, as an alternative to copper washers, you can use a "Dowty-Washer" which has an integral O-ring seal and these washers will not leak, even finger tight!

Sorry !

I was referring to drain-plugs, not spark-plugs. The copper-lube is definately a good idea for the spark-plugs and torque setting will be different whether dry or "oily".

The PTFE tape is good for the drain-plugs, particularly the conical threads on the rear-diff, but don't use it for the spark-plugs!

Yes, the Dowty washer is as you described.

Hi every one.

You have to excuse me but how will an oily plug have a different torque than a dry one, i thought that the torque would be the same but that the part to be tightened may not have achieved the correct angle, hence the term torque and angle when fastening with electronic nut runners?

Allen

Simply because torque required to tighten a nut or plug includes both the force to elastically stretch (tension) the metal fastener as well as to overcome an amount of friction on the screw threads, washers, contact surfaces etc.

Therefore, if the surfaces are oily, the friction is reduced and so the same applied torque will overstretch the metal. So, with oily threads the torque setting should be reduced to achieve the same tension on the metal.

That is why torque wrenching is not an exact science as many people think. There are too many variables.

In many cases, tightening by angle is more precise.

There is a generic spec available...

Browsed through this today.

http://wuffer.net/MyFiles/TorqueSpecs.pdf

for all your torque setting needs

See this link for a comprehensive list of settings.
http://www.mwrench.com/Whitepapers/torqspec.pdf

Zitat von arnie

Simply because torque required to tighten a nut or plug includes both the force to elastically stretch (tension) the metal fastener as well as to overcome an amount of friction on the screw threads, washers, contact surfaces etc.

Therefore, if the surfaces are oily, the friction is reduced and so the same applied torque will overstretch the metal. So, with oily threads the torque setting should be reduced to achieve the same tension on the metal.

That is why torque wrenching is not an exact science as many people think. There are too many variables.

In many cases, tightening by angle is more precise.

Alles anzeigen

Bolt torquing regarding automotive applications actually has only 1 realistic variable. That is the aforementioned lubrication coefficient of friction. If you allow that the difference between "dry" or "lubricated", is also predicated on the "type of lubrication" can be as great as 90% then
you will realise that simple commonsense, ie "feel" is as valid as anything else particularly with items such as drain plugs.

On items like cylinder heads, pump bodies etc. the equal application of an evenly applied torque in a gradual and systematic procedure over the bolted flange is actually more important than the actual torque value used.

I'm not sure where "tightening by angle" comes into this, but I'm sure willing to learn.

Tightening by angle , as the name suggests means hand-tightenting the bolt or plug to the point of contact and then further torquing by rotation through a specified angle.

This works for items such as drain-plugs or spark-plugs, and I've even seen some cylinder-head torquing instructions written in this manner.

The method may not be so goog where you cannot easily determine that the initial hand-tightening has achieved metal-metal contact

The method works because you are moving the thread through a specified angle and therefore achieving a specific strain on the plug or fastener. The amount of rotation is not dependant on friction or lubrication and so the actual torque required to rotate through a given angle is immaterial.

However, I agree that with experience, one can judge the point when a fastener is correctly tightened. I've never used a torque wrench on a car, except for doing cylinder heads but, even then, gradual, progressive tightening and feel are very important.

Aye, can see where your'e coming from there, but, can't recall it being called by "angle". Surely that would be dependent on the length of the lever being used?

30 degrees of arc on a 1' tommy bar would apply a lot more torque than 30 degrees with a 6" bar.

I seem to remember that a lot of tightening procedures referred to "tighten to hand tight, then apply a further 1/4 turn.

Immediately dumps 4 foot scaffold tube "cheater bar".

Sorry,
I'll go get my anorak.

Even if you buy a top of the range certified manual torque wrench you will not get below + / - 3 % of it's posted capability.

Should you be using a torque wrench more than 1 year old then it's possible that the variation may be higher if it hasn't been re-calibrated.

As others have posted, the more you do it, the more knack you get in knowing just how much to apply. ( it's a guy thing!)

Zitat von Hemibum

..........30 degrees of arc on a 1' tommy bar would apply a lot more torque than 30 degrees with a 6" bar.....

The anlge is measured as a rotation of the actual plug or fastener (any deflection of the tommy-bar etc is irrelevant).

It is true that a longer lever will apply more Torque for a given Force (Torque = Force x Distance) and conversely, a shorter lever will require more Force for the same Torque.

But, when tightening by angle, the amount of Force, length of lever (tommy-bar) or actual required Torque (oily or dry) is irelevant. You just apply whatever is necessary to rotate the plug or fastener through the given angle. This will tighten the fastener according to the pitch of its thread.