Torqueing Tension Rod Bushing Nuts?
#1
Torqueing Tension Rod Bushing Nuts?
When replacing the tension rod bushings, which attach the front of the rod to the frame bracket & which are responsible for proper wheel position fore/aft, the procedure is supposed to be as follows:
1) Assemble all components to the rod & bracket
2) Tighten the front nut so that a specific amount of rod protrudes past the nut, and pin it
3) Tighten the rear nut to 80-105ftlbs, to compress the bushings properly.
The last step is key, because both the effective length of the rod and its rigidity change as the bushings are compressed in the "sandwich" between the two nuts.
Here's my problem; I can't figure out any way to ACCURATELY achieve the proper torque, for a few reasions:
1) It's a 26mm nut
2) It's threaded on a rod, and so it's impossible to put a socket on
I can't find anyone selling a crowfoot big enough to fit it, so I can't use my torque wrench on it.
I can guestimate the torque based on the length of my open-end wrench and approximate pull strength, but I'd like to make sure it's in spec.
Anyone have suggestions how to properly torque these nuts?
Separate question: anyone know of a way to check calibration on a "clicker" type torque wrench? I'm kind of suspicious that mine may be reading low, but I've never heard of a way to check one.
1) Assemble all components to the rod & bracket
2) Tighten the front nut so that a specific amount of rod protrudes past the nut, and pin it
3) Tighten the rear nut to 80-105ftlbs, to compress the bushings properly.
The last step is key, because both the effective length of the rod and its rigidity change as the bushings are compressed in the "sandwich" between the two nuts.
Here's my problem; I can't figure out any way to ACCURATELY achieve the proper torque, for a few reasions:
1) It's a 26mm nut
2) It's threaded on a rod, and so it's impossible to put a socket on
I can't find anyone selling a crowfoot big enough to fit it, so I can't use my torque wrench on it.
I can guestimate the torque based on the length of my open-end wrench and approximate pull strength, but I'd like to make sure it's in spec.
Anyone have suggestions how to properly torque these nuts?
Separate question: anyone know of a way to check calibration on a "clicker" type torque wrench? I'm kind of suspicious that mine may be reading low, but I've never heard of a way to check one.
#3
Can you explain it simple? I must be slow today...
#4
Wrkn Toyota, Rootn Wankel
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Oh I thought you were talking about the front nut.
The only thing is that if you start adjusting the rear nut you're adjusting caster, so wouldn't you want to do that on a lift or alignment rack?
As for a suggestion, try to find a 26mm or inch equivilant (1 1/8" If I remember right) crow's foot to use if you want to make an accurate attempt at torquing it.
My bad misunderstood which nut we're talking about.
The only thing is that if you start adjusting the rear nut you're adjusting caster, so wouldn't you want to do that on a lift or alignment rack?
As for a suggestion, try to find a 26mm or inch equivilant (1 1/8" If I remember right) crow's foot to use if you want to make an accurate attempt at torquing it.
My bad misunderstood which nut we're talking about.
#7
Old Fart Young at Heart
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The rear nut sets caster, leave it in place and don't move it. There is a chance that the new bushings can change the caster setting so you may need an alignment anyway. In a pinch, you could find a fish scale, the kind one hangs the from, then use the length of the wrench as a torque multiplier. If you hold the scale at 1 ft. from the center of the rod, that's a 1:1 multiplier. With a 2' bar you only need 20-22.5 lbs. of pull. Since the front nut is secured with a large cotter pin, there's no danger of the nut coming off. There is the possibility of the nuts loosening and causing rattle, but it won't come apart.
I would let the alignment shop deal with setting torque.
I would let the alignment shop deal with setting torque.
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#8
1200 gone......but......
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You have to look for the JUMBO crows foot set. You can get them from ebay, long beach swap meet, harbor freight? Ebay has the Sunex jumbo crows foot set 24mm - 32 mm for a good price.
You can borrow my set if my friend ever gives them back to me. I just sent him an e-mail so I hope he replies soon. Quick to borrow, but a flake when it's time to return the tools!!!!!
You can borrow my set if my friend ever gives them back to me. I just sent him an e-mail so I hope he replies soon. Quick to borrow, but a flake when it's time to return the tools!!!!!
#10
The rear nut sets caster, leave it in place and don't move it. There is a chance that the new bushings can change the caster setting so you may need an alignment anyway. In a pinch, you could find a fish scale, the kind one hangs the from, then use the length of the wrench as a torque multiplier. If you hold the scale at 1 ft. from the center of the rod, that's a 1:1 multiplier. With a 2' bar you only need 20-22.5 lbs. of pull. Since the front nut is secured with a large cotter pin, there's no danger of the nut coming off. There is the possibility of the nuts loosening and causing rattle, but it won't come apart.
I would let the alignment shop deal with setting torque.
I would let the alignment shop deal with setting torque.
I wasn't sure if they'd torque it as a matter of course doing an alignment, or on request - - have in the past dealt with alignment shops that seemed more interested in convincing me I had (known good) parts needing replacing than in acutally doing the alignment.
Without loosening the rear nut, it would have been impossible to get the front nut back on with the new bushings; uncompressed bushing stack thickness was more than the distance from the rear nut to the rod tip.
All good advice; thanks for it!
#11
Wrkn Toyota, Rootn Wankel
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Wait, why did you have trouble taking it off?
I undid the two anchor bolts on the control arm and then slid the rod out when I did mine, came out easy and only required a little effort to realign the two anchor bolts.
I undid the two anchor bolts on the control arm and then slid the rod out when I did mine, came out easy and only required a little effort to realign the two anchor bolts.
#15
I grew up in Nebraska; dealing with fender cancer was some of my earliest mechanical experience.
#19
When replacing the tension rod bushings, which attach the front of the rod to the frame bracket & which are responsible for proper wheel position fore/aft, the procedure is supposed to be as follows:
1) Assemble all components to the rod & bracket
2) Tighten the front nut so that a specific amount of rod protrudes past the nut, and pin it
3) Tighten the rear nut to 80-105ftlbs, to compress the bushings properly.
The last step is key, because both the effective length of the rod and its rigidity change as the bushings are compressed in the "sandwich" between the two nuts.
Here's my problem; I can't figure out any way to ACCURATELY achieve the proper torque, for a few reasions:
1) It's a 26mm nut
2) It's threaded on a rod, and so it's impossible to put a socket on
I can't find anyone selling a crowfoot big enough to fit it, so I can't use my torque wrench on it.
I can guestimate the torque based on the length of my open-end wrench and approximate pull strength, but I'd like to make sure it's in spec.
Anyone have suggestions how to properly torque these nuts?
Separate question: anyone know of a way to check calibration on a "clicker" type torque wrench? I'm kind of suspicious that mine may be reading low, but I've never heard of a way to check one.
1) Assemble all components to the rod & bracket
2) Tighten the front nut so that a specific amount of rod protrudes past the nut, and pin it
3) Tighten the rear nut to 80-105ftlbs, to compress the bushings properly.
The last step is key, because both the effective length of the rod and its rigidity change as the bushings are compressed in the "sandwich" between the two nuts.
Here's my problem; I can't figure out any way to ACCURATELY achieve the proper torque, for a few reasions:
1) It's a 26mm nut
2) It's threaded on a rod, and so it's impossible to put a socket on
I can't find anyone selling a crowfoot big enough to fit it, so I can't use my torque wrench on it.
I can guestimate the torque based on the length of my open-end wrench and approximate pull strength, but I'd like to make sure it's in spec.
Anyone have suggestions how to properly torque these nuts?
Separate question: anyone know of a way to check calibration on a "clicker" type torque wrench? I'm kind of suspicious that mine may be reading low, but I've never heard of a way to check one.
I replaced those bushings before on one of my old fb's that I know longer have. I know what you mean about a not knowing how to properly torque them. I felt I was 100% guessing as the poly bushings i was using were fatter than the squished stock ones. I'll probably not mess with those bushings until I figure out how to do it right. I wish I knew the answer to that question. Good Luck.