Original battery hold down bolt

[Scott69Z]

Could someone please help me by posting a picture of a correct battery hold down bolt. When I purchased my 69 Z28 it was missing the battery hold down and bolt. I purchased an original gm battery hold down and an amk under hood detailing kit which includes the battery hold down bolt. The bolt in the kit seems to be too short. I purchased a sealed R59 battery and I cannot seem to get this bolt to work. Thanks for the help.

[lakeholme]

http://www.camaros.org/forum/index.php?topic=2899.0

Maybe JohnZ can re-post the pic. I couldn't get it to open.

[JohnZ]

Here's the bolt on mine.

[Scott69Z]

Thanks for the pic. Does anyone know how long this bolt is suppose to be? Mine seems too short.

[68camaroz28]

http://www.camaros.net/forums/showthread.php?t=182584&highlight=3881339&page=35
Open up this team camaro link to our build thread and at the top of that page I have posted pics of original hold down clamps and a bolt. I have four original bolts (all in use) and they were all RBW with an oversize captured washer which makes it unique. Do not remember the length.

[68camaroz28]

http://www.camaros.net/forums/showthread.php?t=182584&highlight=3881339&page=35
Open up this team camaro link to our build thread and at the top of that page I have posted pics of original hold down clamps and a bolt. I have four original bolts (all in use) and they were all RBW with an oversize captured washer which makes it unique. Do not remember the length.

Update: I found one of my bolts to be a anchor supplied bolt. The large captured washer is approximately .85" in diameter and thread length is just under an inch.

[big iron]

Seems to be two points of view here and in other threads I have looked at.
Let's look at the facts as presented in the AIM's
Same part number 3758783 and torque used in all three years of production for this particular bolt.
Why would the torque of 60-80 in lbs (6.6 ft lbs) be applied to this bolt when the same size bolts in the same area have 120-180 in lbs (12 ft lbs) applied to them.
I believe that the toothed conical washer was specified and thus the lower torque value.
If anyone has ever tried to change a battery in a first gen then you know why the lead point on the bolt was specified, especially with AC (67-68).
I bring these points of view, not to start an argument, but to reason why this particular bolt does not have an accepted specific style and measurement.
Thanks,
Bob

[JohnZ]

Same part number 3758783 and torque used in all three years of production for this particular bolt.
Why would the torque of 60-80 in lbs (6.6 ft lbs) be applied to this bolt when the same size bolts in the same area have 120-180 in lbs (12 ft lbs) applied to them.

On the battery hold-down application, the bolt is bearing down (through the clamp) on a molded tab that's part of the plastic battery case - a "soft make-up" application; too much torque, you break the case and have acid everywhere. Other applications using the same bolt join two steel parts, with "hard make-up" joints.

[big iron]

Same part number 3758783 and torque used in all three years of production for this particular bolt.
Why would the torque of 60-80 in lbs (6.6 ft lbs) be applied to this bolt when the same size bolts in the same area have 120-180 in lbs (12 ft lbs) applied to them.

On the battery hold-down application, the bolt is bearing down (through the clamp) on a molded tab that's part of the plastic battery case - a "soft make-up" application; too much torque, you break the case and have acid everywhere. Other applications using the same bolt join two steel parts, with "hard make-up" joints.

John,
How would the bolt stay tight at half of it's recommended torque?
Is the plastic case compressing and compensating for the lack of bolt stretch or are the teeth on the conical washer keeping the bolt tight?
Bob

[JohnZ]

John,
How would the bolt stay tight at half of it's recommended torque?
Is the plastic case compressing and compensating for the lack of bolt stretch or are the teeth on the conical washer keeping the bolt tight?
Bob

"Recommended torque" on a fastener is determined by Fastener Engineering based on the type of joint and the joint materials involved; the fastener's job is to establish and maintain clamping force in the joint, and the torque required to do that is a function of the materials in the joint.

[big iron]

John,
How would the bolt stay tight at half of it's recommended torque?
Is the plastic case compressing and compensating for the lack of bolt stretch or are the teeth on the conical washer keeping the bolt tight?
Bob

"Recommended torque" on a fastener is determined by Fastener Engineering based on the type of joint and the joint materials involved; the fastener's job is to establish and maintain clamping force in the joint, and the torque required to do that is a function of the materials in the joint.

In this case was the conical toothed washer used to maintain clamping force because of the soft joint? If not, why was toothed washer specified in this case?
Bob

[68camaroz28]

John,
How would the bolt stay tight at half of it's recommended torque?
Is the plastic case compressing and compensating for the lack of bolt stretch or are the teeth on the conical washer keeping the bolt tight?
Bob

"Recommended torque" on a fastener is determined by Fastener Engineering based on the type of joint and the joint materials involved; the fastener's job is to establish and maintain clamping force in the joint, and the torque required to do that is a function of the materials in the joint.

In this case was the conical toothed washer used to maintain clamping force because of the soft joint? If not, why was toothed washer specified in this case?
Bob

Are you referring to the battery hold down bolt #3758783 Bob? It did not have a conical toothed washer that I'm aware of, just that oversize captured washer.

[big iron]

Chick,
Yes.
The questions I have asked have arisen from reply #1 which indicates two types of bolts being used on survivors but only one type was factory specified.
Just trying to find an engineering answer to my reply #6 and now reply #10.
Bob

[JohnZ]

John,
How would the bolt stay tight at half of it's recommended torque?
Is the plastic case compressing and compensating for the lack of bolt stretch or are the teeth on the conical washer keeping the bolt tight?
Bob

"Recommended torque" on a fastener is determined by Fastener Engineering based on the type of joint and the joint materials involved; the fastener's job is to establish and maintain clamping force in the joint, and the torque required to do that is a function of the materials in the joint.

In this case was the conical toothed washer used to maintain clamping force because of the soft joint? If not, why was toothed washer specified in this case?
Bob

I guess you'd have to ask the responsible release engineer about the specifics.

[KurtS]

Clamping force required, that's all. They worked out the force required for the battery and generated the spec. Sure don't want to have the battery loose or crack the case.