Retorqueing Composite Headgaskets.

[rebelrouser]

Little off point- for a guy that doesn't make his living off of professional tools- what is a good value you have noticed for 1/2 torque wrench, I bough a KD for lug nuts and I know it's off by 10ft-lbs. I'm guessing just buy a used SO or MAC and take it to the local dealer for calibration??

I have had snap-on torque wrenches for my entire career, started fixing cars in 1974. When I taught at the tech college, we had a torque wrench tester in the tool room. The students were supposed to buy their own torque wrenches, but we kept about ten for those that did not have them yet or special uses etc. You would be surprised how many cheap torque wrenches flunked when I tested them before letting them be used in the shop.

[rebelrouser]

Little off point- for a guy that doesn't make his living off of professional tools- what is a good value you have noticed for 1/2 torque wrench, I bough a KD for lug nuts and I know it's off by 10ft-lbs. I'm guessing just buy a used SO or MAC and take it to the local dealer for calibration??

Also the type of torque wrench you twist the handle to set, must be turned back to zero when you get done using it. If you leave it in your toolbox tightened down, it will kill the calibration.

[dfarr67]

Little off point- for a guy that doesn't make his living off of professional tools- what is a good value you have noticed for 1/2 torque wrench, I bough a KD for lug nuts and I know it's off by 10ft-lbs. I'm guessing just buy a used SO or MAC and take it to the local dealer for calibration??

I have had snap-on torque wrenches for my entire career, started fixing cars in 1974. When I taught at the tech college, we had a torque wrench tester in the tool room. The students were supposed to buy their own torque wrenches, but we kept about ten for those that did not have them yet or special uses etc. You would be surprised how many cheap torque wrenches flunked when I tested them before letting them be used in the shop.

You would be surprised- no.... I don't think I would, hence the question.

[dfarr67]

Little off point- for a guy that doesn't make his living off of professional tools- what is a good value you have noticed for 1/2 torque wrench, I bough a KD for lug nuts and I know it's off by 10ft-lbs. I'm guessing just buy a used SO or MAC and take it to the local dealer for calibration??

Also the type of torque wrench you twist the handle to set, must be turned back to zero when you get done using it. If you leave it in your toolbox tightened down, it will kill the calibration.

Yep.....

[dfarr67]

Little off point- for a guy that doesn't make his living off of professional tools- what is a good value you have noticed for 1/2 torque wrench, I bough a KD for lug nuts and I know it's off by 10ft-lbs. I'm guessing just buy a used SO or MAC and take it to the local dealer for calibration??

Precision Instruments

I bought a used torque wrench, (Snap-On) and then had it checked. No parts available, didn't meet calibration specs. Torque wrench was scrapmetal.

Go on Amazon, look at Precision Instruments and CDI.

Keep in mind:
1. Team Torque and Angle Engineering charge DOUBLE to test/calibrate electronic torque wrenches compared to "clickers".
2. "Split Beam" torque wrenches generally cannot torque in the reverse direction, and usually don't have a ratchet head that can be reversed. But at least you don't have to reset the torque adjustment to the bottom of the scale after use.
3. "Deflecting Beam" torque wrenches have fabulous inherent accuracy and cheap pricing. The inherent accuracy goes away because of the user-error they promote. Unless you're testing torque--like determining bearing preload on a differential assembly--"Deflecting beam" torque wrenches are for the birds.

50-250 or 0-100 ??

[BOOT]

It's being tuned on a chassis dyno, so if they don't push the gasket it will be good to go for retorque.

Got a larger Precision Instruments for wheel nuts n higher ft-lb stuff, I like it but prefer my 1/2" craftsmen for heads. Not long ago bought a couple CDI 1/2 & 3/8 but not used them yet, got them from Zoro with a promo code. Sears had a nice sale back during Xmas on their 1/2" digital & non. Prices are higher now but still not bad. The Digital was $69.99 I think(out of stock by time I saw the deal or I'd of gotten one) and I bought the non for $39.99+10 shipping to use on tires n such.

https://www.sears.com/craftsman-1-2inch ... A102532156
https://www.sears.com/craftsman-1-2-822 ... A102532141

[Tom68]

Just make sure you have a torque wrench with an easy to read scale.
Those chrome micrometer scales are an error just waiting to happen.

[fabr]

Right , wrong,otherwise, for the last couple years I have had zero faith in any of my torque wrenches setting accuracy. As a last resort I bought 2 of these https://www.harborfreight.com/12-in-dri ... 58706.html. I didn't want to trust HF accuracy hence the 2 being bought. To my amazement both read within 1 lb.ft. of each other at high/med/low readings and was within 2 of my recently calibrated 1/2 in.wrench. I now set my wrenches with them and ignore the setting on the wrench. Comes in really handy when using a crows foot box end for those hidden head stud nuts on some heads. I just use 2 torque wrenches ,both set to required torque with the HF adapters regardless of the wrench indication. I just put the male end in the vice and torque wrench in the female end and adjust torque wrench according to the readout on the adapter.

[Schurkey]

I bought a used torque wrench, (Snap-On) and then had it checked. No parts available, didn't meet calibration specs. Torque wrench was scrapmetal.

50-250 or 0-100 ??

My scrap-metal torque wrench?

It's a small "1/4 drive" torque wrench that has a 3/8 drive ratchet head in it. 5--25 ft/lbs, maybe. The little guy in this photo. From top, Jo-Line 3/8 drive inch-pound that goes to 750, Mac 3/8 drive, 20-100 ft/lb, the scrap Snappy, a Mac 1/2 drive 50-250 ft/lb, and a Snappy torque tester.

Torque_Wrenches.jpg

[David Redszus]

The inaccuracy of a torque wrench is often dwarfed by the inaccuracy of the friction torque method.

[FC-Pilot]

Right , wrong,otherwise, for the last couple years I have had zero faith in any of my torque wrenches setting accuracy. As a last resort I bought 2 of these https://www.harborfreight.com/12-in-dri ... 58706.html. I didn't want to trust HF accuracy hence the 2 being bought. To my amazement both read within 1 lb.ft. of each other at high/med/low readings and was within 2 of my recently calibrated 1/2 in.wrench. I now set my wrenches with them and ignore the setting on the wrench. Comes in really handy when using a crows foot box end for those hidden head stud nuts on some heads. I just use 2 torque wrenches ,both set to required torque with the HF adapters regardless of the wrench indication. I just put the male end in the vice and torque wrench in the female end and adjust torque wrench according to the readout on the adapter.

I worked for a company that did calibration and certification. We had three of those Harbor freight digital deals come through. They were as accurate or better than any of our companies high end torque wrenches. After that I bought one myself and had it certified. Many of the torque wrenches we would cal and cert had areas of inaccuracy. We would adjust them to be “within spec” or if the user had a certain range they used most we would get them closest in that range, as long as the other side of the range stayed within spec. Otherwise we would have to split the difference.

(Before you ask, it was over a decade ago so I don’t remember the the +/- allowance was).

Paul

[digger]

IMO You dont need a fancy torque wrench for head bolts/ studs

[dfarr67]

IMO You dont need a fancy torque wrench for head bolts/ studs

Agreed- but I have to do better than +-10lbs.

[billet]

The inaccuracy of a torque wrench is often dwarfed by the inaccuracy of the friction torque method.

^^I can not agree with this more^^

While I'm far from a professional engine builder, but a simple test can show you how much this effects things.

1. Torque head bolts or studs with like described by many methods or manufacturers. Many may be a step method of jumps in 10 to 20# increments.
2. After you're done doing the sequence and pattern on the head and think you're finished, go back and mark the bolt or nut with a marker in the top position so you can reference how far the fastener is turned.
3. Loosen one fastener about a 1/4 turn and retorque it to full value in one brisk smooth pull without stopping before reaching the max torque (wrench clicks or beeps)
4. Look at mark on fastener? it's likely an 1/8 of a turn more. This is do to break away torque from step torquing and/or the not all fasteners being fully tight when doing the one you just did.

I've done it this way for years and find you don't need to retorque after the motor runs in most cases. Recheck the same way and you will see the marks end up in the same positions.

[dfarr67]

Can you self calibrate a clicker wrench by using a digital inline torque indicator as linked in a vise? Set the electronic T/W to 100lbs and sneak up on it with the clicker adjustment.