Higher torque wrench alternative?

[Achilleus]

Greetings.

First post here! I need to torque a crank pulley bolt to 285 ft-lb, and don't want to shell out big bucks on a 0-600 ft-lb wrench. Tried autozone, no luck. So is there a way to accurately double-up the torque from a 200-lb wrench?

If the right answer is that it just don't matter and just heave at it, then fine, its an old car anyway! Also, I won't be upset if this is the wrong forum and one of you tells me 'oh yea there's a better club just for automotive tools on XXXX'.

Cheer and thanks for any info,
Dean

 

[dwm]

Torque multiplier, though a good one isn't cheap and they're not always easy to use.

 

[Jack Olsen]

Or simply do the math. Foot pounds are exactly that. If you weigh 143 pounds, then apply your full weight to the nut 24" out on a horizontal cheater bar. Or if you weigh 285 pounds, you only need to be 12" from center on the handle.

That's assuming you have clear access to it.

I had to do 340 ft-lbs on my axle nut.

 

[diesel research]

A manual torque multiplier isn't necessarily an accurate method. You have gear train loss in an unspecified amount, typically 10-20%. W/O knowing exactly what that percentage is, it is the same as assuming torque at flywheel and ground are the same. Obviously they aren't, again due to frictional losses.

I can't say what I would likely do in this situation, because I would sound like a hackjob....

 

[Moose-LandTran]

Know anyone that has one and borrow it?

I can't say what I would likely do in this situation, because I would sound like a hackjob....

250lb/ft off a "normal" large 1/2" torque wrench + a bit more? (That's what i'd do if i had no alternative..)

 

[Achilleus]

Jack - are you putting more torque than the click on that setup? For some reason I thought that was bad for the wrench.

 

[diesel research]

Know anyone that has one and borrow it?



250lb/ft off a "normal" large 1/2" torque wrench + a bit more? (That's what i'd do if i had no alternative..)

Pretty much. If concerned about exceeding the range, it would take 10 seconds to swap to a breaker bar. Wanna get real fancy? Could put a paint dot (white out) aligning the socket and a fixed point to gauge additional rotation. that's way overkill and I would likely just nudge it some part of a turn.

This would be for older non TTY bolts of course.

If spec was listed as dry, I might use the cheater method, clean the threads and lightly lube them, which gives a slightly increased clamping force for a given resistance.

 

[Moose-LandTran]

Jack - are you putting more torque than the click on that setup? For some reason I thought that was bad for the wrench.

I believe that's just a ratchet with a pipe over it.

You're correct, exceeding the "click point" on a click-type torque wrench can damage it. The internal extension spring can be stretched and will throw the wrench out of calibration, often rendering the wrench useless without stripping it down and replacing the spring, then recalibrating.

Not in every case, but it's a risk.

Pretty much.

Great minds think alike!

 

[Givl Reggin]

I need to torque a crank pulley bolt to 285 ft-lb,.. torque from a 200-lb wrench?

I know a lot of guys are pretty particular about following torque values,and I am too about somethings, but 99% of the time I've found the best torque wrench is the one that connects the hand to the brain.

What I would do in your situation is set your torque wrench 200 ft/lbs, then take a breaker bar and give the bolts another 1/4 turn and call it a day.

 

[Jack Olsen]

Jack - are you putting more torque than the click on that setup? For some reason I thought that was bad for the wrench.

MooseLand-Tran is right. That's just a regular 3/4" ratchet wrench. I'm not an engineer, but if you apply one pound of force on a lever one foot out from the fastener, then you've got a foot-pound. You don't need anything to click, you just need to know what the force is.

So if you need 285 pounds of torque, then have a 285 pound guy stand on the wrench handle exactly one foot out. Or a 142-1/2-pound guy stand on it two feet out. Or a 95-pound guy three feet out on a cheater bar.

Or say you need 142-1/2 pounds 24" out -- but you weigh 200 pounds. You can stand on a bathroom scale while applying force downward at the 24" mark and then push until the bathroom scale shows your weight at 57-1/2 pounds. The other 142-1/2 pounds will be taken by the wrench at that point, and you'll know you're pretty close to the right amount of torque.

If you're not able to turn the wrench up and down, though (like if the bolt turns horizontal or at an angle) -- then you'll need another method.

 

[jhelrey]

Borrow a 250# wrench and torque to that. Then give it another snug. Or do what someone said about and put it at 200# and just nudge it another 1/5-1/4 turn.

 

[bobcatdan]

When it comes to torqueing over 250 ft lbs, your options are a torqure multipler or 3/4" torque wrench, neither are cheap, I have a central mulltipler and a PI 3/4 torque wrench, both over $400 a piece. The wrench is easier to use, but the multipler will gey you close to 1000 factoring in torque lose. Also a multiper can be used in reverse to break **** lose. It's not righr but I have used a 3/4 impact threw mine to loosen stuff. If you only need to make it to 285, I agree with torque to 250 and give it a little more, it takes so little movement of a wrench to reach another 30 or so ft lbs.

 

[tankboy_taylor]

torque to 250 then apply another 1/8 to 1/4 turn

 

[Moose-LandTran]

Find a suitable spring balance, work out the force to pull on it and the distance. BAM. Homemade torque wrench. Works in any axis.