Rear composite spring torque spec
05-27-2013, 01:03 PM
#1
Race Director
Thread Starter
Rear composite spring torque spec
Looks like this will be my wtf for the day. A couple of weeks back, I found an Allen head bolt under the car. I guessed it was for the rear sway bar but just didn't get a chance to look until today. Those bolts are fine, as are all the drive and half shaft bolts. Instead, I found one of the four bolts that hold the composite spring almost ready to fall off. The other forward bolt was loose but not nearly as much. The other two seem fine.
First question, what is the torque spec?
Second question, do these loosen up as the rubber shrinks? Is this an issue?
Always something. Still have no idea of where the bolt came from.
First question, what is the torque spec?
Second question, do these loosen up as the rubber shrinks? Is this an issue?
Always something. Still have no idea of where the bolt came from.
05-27-2013, 01:48 PM
#2
Race Director
Thread Starter
When is the sound of breaking steel a good thing?
When it doesn't cost as much as you initially thought.
This would be best read with the accompaniment of continuous swearing. I've worked with Marines, so I put my swearing skill level somewhere between Corporal and Sargeant. Too bad I'm not any good at recording video on my camera.
I found the torque spec on the VB&P web site: 40 to 45 foot pounds. Also instructed to tighten evenly. I also remember reading Gary's differential posts on cracking covers with wrong sized bolts. Since I had no idea of where these came from so I proceeded slowly. 12 pounds all around, then 18, then 22, then colossal sound of metal breaking. Begin swearing.
As a bit of background, I'm in the process of moving from the Bay area of California to Boston. A differential rebuild doesn't easily fit in the program right now.
Once I was able to get my swearing slightly under control, I crawled back underneath and, after wiping the forehead blood off of the undercarriage, I notced the the retaining plate split in two. Been a long time sine I've been thrilled with breaking something in half.
VB&P has a sale on this weekend too
Edit: Important clarification. The retaining plate is aluminum and not steel
This would be best read with the accompaniment of continuous swearing. I've worked with Marines, so I put my swearing skill level somewhere between Corporal and Sargeant. Too bad I'm not any good at recording video on my camera.
I found the torque spec on the VB&P web site: 40 to 45 foot pounds. Also instructed to tighten evenly. I also remember reading Gary's differential posts on cracking covers with wrong sized bolts. Since I had no idea of where these came from so I proceeded slowly. 12 pounds all around, then 18, then 22, then colossal sound of metal breaking. Begin swearing.
As a bit of background, I'm in the process of moving from the Bay area of California to Boston. A differential rebuild doesn't easily fit in the program right now.
Once I was able to get my swearing slightly under control, I crawled back underneath and, after wiping the forehead blood off of the undercarriage, I notced the the retaining plate split in two. Been a long time sine I've been thrilled with breaking something in half.
VB&P has a sale on this weekend too
Edit: Important clarification. The retaining plate is aluminum and not steel
Last edited by CA-Legal-Vette; 05-27-2013 at 02:51 PM.
05-27-2013, 04:46 PM
#3
Melting Slicks
Hey Mike, Glad it wasnt as bad as you first thought! Not sure I can imagine anything much worse than the odd Bloody coming from you but hey what do I know! lol.
Regards to all!
Regards to all!
05-27-2013, 08:20 PM
#4
Instructor
OP, my experience when tightening these bolts to the spec listed (40-45 ft./lbs) was that when using a torque wrench and carefully bringing up to the expected limit it seemed to take forever to bring it up to the final few ft./lbs.
I knew something was wrong and immediately switched to a second torque wrench to verify the reading I was getting.
What I found was that the material (spacer and spring) is "plastic" and deforms thus reducing the reading rather quickly.
When I finally achieved the desired spec I left it over night and checked again and the torque spec read almost 7 ft/lbs less than the day before.
I called the Tech Support line and advised them of this, however no solution or advice was given in terms of whether this damaging to the spring and mounting hardware.
I wish I could offer some direction but I cannot - I can understand how this could happen though !
I knew something was wrong and immediately switched to a second torque wrench to verify the reading I was getting.
What I found was that the material (spacer and spring) is "plastic" and deforms thus reducing the reading rather quickly.
When I finally achieved the desired spec I left it over night and checked again and the torque spec read almost 7 ft/lbs less than the day before.
I called the Tech Support line and advised them of this, however no solution or advice was given in terms of whether this damaging to the spring and mounting hardware.
I wish I could offer some direction but I cannot - I can understand how this could happen though !
