Torque wrench maintenance ?

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I have a click type SK torque wrench that I got maybe fifteen years ago. I used it a handful of times and always kept the tension backed off it while it was stored, and it was always oiled. Is there something that I missed that I should have done to it?
Were putting a new crank in a motor that my best friend built. It was the last one that he put together before he died so I want to make sure that nothing will go wrong with the torque specs. Should I have it calibrated ? Where would I get that done ?
Any info would be appreciated.

 

[sberry]

There is quite a bit of variation in common engine bolts, pick a spot in the middle and go for it.

 

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What do you mean ? Shouldn't torque specs be followed precisely ?

 

[brveagle]

If you do a google search, there will be many torque wrench calibration results. I researched this for a while before talking to a dealership buddy with a snap on man. He came by and i dropped it off with him for calibration.

 

[SuzukiGS750EZ]

If it's only been used a few times i wouldn't worry too much. Being a bit off won't hurt anything. Bolt stretch, how clean the threads are, if you sneezed on the torque wrench, the humidity in the air, they all factor in. I'm sure it will be fine as it sits.

 

[sberry]

Agree. Some are more fussy, some give some variation. If it isn't beat to sheet it will work just fine. Chebby lists say 95 and some Fords allow for 10% variation.

 

[T45]

Shelf life of grease varies, but 15 years does run risk of some lube drying out.

There are ways to sanity check a wrench short of a full calibration. Checkin it is reasonably close might be prudent. The real danger is if the thing is way out of spec or doesn't click at all until you've stripped out some threads. Even/consistent torque measurement but out of spec by 1% is not really the catastrophed you are trying to avoid in most cases.

In fact, an actual testing prodcedure only actively changes (calibrates) when its out of spec. Its very possible for you to send in the wrench and nothing has been done to it maintenance wise, just tested with a pattern of clicks (17-20) and verified it works throught the viable range (20-100% of scale).

You can always send it in for repair/maintenance in any event. Just make sure to read up on the place and inquire about the method of service. Many places only will certify or work on tools reasonably current (ie, with spare parts available) and whatever else they choose to limit in terms of intake.

One other piece of advice is to warm up the wrenche with some clicks before you go to us it the first time. And to run it up through/down the range as well to just make sure all adjustments are working -- this helps with lubrication to even it out from sitting in place.

 

[sberry]

I got a couple, a snap dial must be 60 yrs old and never check the thing except for a rudimentary one as was splained above. I check it against a beam, its so super close I aint worried.

 

[jumbojak]

You could check the wrench yourself. T=f•D so all you need to do is check that it operates clicks when the correct force (weight in this case) is applied to the handle.

 

[mjoekingz28]

I ditched my Harbor Freight ones. I remember doing tie rod work on a Dodge and using both the 3/8 and 1/2 in the 40-60fl-lb range and they would not match up.....meaning one or both were wrong.

Anyways, that is not why I ditched them. It was just too nerve racking waiting for a click on a critical fastener.




As has been said, according to the Pittburgh manual....clicking it, keeping it clean and treating it delicately are good maintenance.




I suggest to you that if a bolt calls for 25lb-ft, that you set your wrench to 15 then turn til it clicks......then go to 20 and wait for a click,.....then finally onto a torque value of 24 or 25 pound feet. Reasoning being, as was said, you dont want the very tool that is supposed to keep you from making mistakes to actually cause damage.

 

[guy48065]

Invest in one of those $30 HF digital torque adapters and verify your wrench against it for continued peace of mind. They are incredibly accurate and the peak hold feature works perfectly at capturing the break-over peak of a clicker wrench.

 

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I ditched my Harbor Freight ones. I remember doing tie rod work on a Dodge and using both the 3/8 and 1/2 in the 40-60fl-lb range and they would not match up.....meaning one or both were wrong.

Anyways, that is not why I ditched them. It was just too nerve racking waiting for a click on a critical fastener.




As has been said, according to the Pittburgh manual....clicking it, keeping it clean and treating it delicately are good maintenance.

I need to do the click thingie




I suggest to you that if a bolt calls for 25lb-ft, that you set your wrench to 15 then turn til it clicks......then go to 20 and wait for a click,.....then finally onto a torque value of 24 or 25 pound feet. Reasoning being, as was said, you dont want the very tool that is supposed to keep you from making mistakes to actually cause damage.

Sound advice, thanks.

Invest in one of those $30 HF digital torque adapters and verify your wrench against it for continued peace of mind. They are incredibly accurate and the peak hold feature works perfectly at capturing the break-over peak of a clicker wrench.

I didn't even know that existed. I think I'll take a look at one.

 

[Adam.C]

I suggest to you that if a bolt calls for 25lb-ft, that you set your wrench to 15 then turn til it clicks......then go to 20 and wait for a click,.....then finally onto a torque value of 24 or 25 pound feet. Reasoning being, as was said, you dont want the very tool that is supposed to keep you from making mistakes to actually cause damage.

this is bad advice and bad practice. Fastener must be moving when you get to the click. Ideally at least 1/4 turn. You can't torque then retorque slightly higher. You won't get the preload associated with the higher torque value.

If you are worried about achieving correct fastener preloads:
1) make sure all mating surfaces are CLEAN and lubed correctly.
2) use proper torque wrench technique.
3) take care of your tools. mechanical torque wrenches must be exercised at the desired setting 5-10 times prior to use if it has been sitting for a prolonged period.

 

[sberry]

just curiou but if we buy adapter what's the point of the wrench?

 

[timothylockhart]

just curiou but if we buy adapter what's the point of the wrench?

It's now a breaker bar [emoji13]

Sent from my LGLS991 using Tapatalk

 

[Davefr]

You could check the wrench yourself. T=f•D so all you need to do is check that it operates clicks when the correct force (weight in this case) is applied to the handle.

^^^This.

It's easy to do. Just tie a pail to the handle, clamp the end and add sand or water until it clicks. Then weigh the pail and do the math.

There are youtube videos showing this.

 

[guy48065]

just curiou but if we buy adapter what's the point of the wrench?

Although the digital adapter is intended to replace standard torque wrenches, I think it's too long, the beep is too quiet and the display too small & facing the wrong direction to be used like that.

It DOES make an excellent comparison standard and those negatives no longer matter in that application.

 

[Rickss96]

Invest in one of those $30 HF digital torque adapters and verify your wrench against it for continued peace of mind. They are incredibly accurate and the peak hold feature works perfectly at capturing the break-over peak of a clicker wrench.

I didn't even know that existed. I think I'll take a look at one.

Spend some time looking at the 1-, 2-, and 3-star reviews on the Harbor Freight site before spending your money. This looks like the typical low-quality HF electrical device. Many reviews mention very poor battery life, can't even finish torqueing a few bolts before it dies. More importantly, several mention problems with its accuracy, e.g.:

"...According to the enclosed "Certificate of Inspection", the error rate was 0.11% @ 88.5 ft-lb. Awesome right? But when this reading was checked on a Tohnichi torque wrench tester at a local shop, (a $4k unit) it was actually off by 7.73 ft.-lbs..."

and another

"All readings I got were consistently 30% under. I tested it against 5 digital torque wrenches from 10-20ft, 20-100, and 50-250 ft. The values I set were all in the middle range of my torque wrenches and yet this torque adapter shows 30% under in all cases...."

Don't want to turn this into another Harbor Freight bashing thread, just be careful before buying an inexpensive device to calibrate your torque wrench.

 

[matt_i]

The F * D testing is the simplest, easiest, and the way that most electronic checkers are referenced back to NIST anyway...

 

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Oh man im glad I started this thread. I have alot of stuff to look at. My buddy ended up using his uncles beam torque wrench so the pressure is off for this project, but I will be looking into all this for when I start putting together my 400 Pontiac .

 

[T45]

... just be careful before buying an inexpensive device to calibrate your torque wrench.

Sanity checking at with a cheap wrench is fine, provided that something is reliable ... A NOS beam wrench is a good place to begin...