'67 Battery tray bolts with factory A/C

[Leif A.]

Looking at the AIM C60, E2 I don't find the answer to my question. The six bolts that hold the battery try to the frame are a 5/16
-18X/78" pointed bolt with captured washer. These do not appear to be self threading bolts, so were there weld nuts in the frame or was the frame threaded to accept the bolt? My question arises as two of my six bolts spin freely in their holes.
Short of disassembling the car, I'm looking for suggestions to fix the stripped out holes.
Thanks for any constructive advice in advance.

[Edward J.]

Re: '67 Battery tray bolts with factory A/C

Looking at the AIM C60, E2 I don't find the answer to my question. The six bolts that hold the battery try to the frame are a 5/16
-18X/78" pointed bolt with captured washer. These do not appear to be self threading bolts, so were there weld nuts in the frame or was the frame threaded to accept the bolt? My question arises as two of my six bolts spin freely in their holes.
Short of disassembling the car, I'm looking for suggestions to fix the stripped out holes.
Thanks for any constructive advice in advance.

Leif, I remember asking about the battery tray bolts many years ago on my 63- they were a fine thread bolt with a flat washer which makes sense , the frame thickness was not that thick. So a coarse thread may strip out easier. I do not have an aim for 67 but think I would check the part number and maybe David Bartush, can look up the correct bolts.

[Leif A.]

Re: '67 Battery tray bolts with factory A/C

Ed,
Thanks for your reply. I have the correct bolts, they are like the one's I pictured in my post...that's not the issue. The part #9422606 I have. I'm trying to find out if there is a weld nut in the frame or if the frame was threaded because I have two bolts that twirl in their hole and won't tighten. Trying to figure out what to do about solving this. I can barely see both bolts, and can grab both of them and remove but to get in there and do any type of Rivnut or similar is not possible. Looking for a creative solution. Thanks again.

[Gary B.]

[Robert P.]

Re: '67 Battery tray bolts with factory A/C

On a 66 frame they used a threaded insert, like a nutsert in todays world can't imagine 67 would be different. It would be fairly easy to install them and you would be the only one that knows
Bob Peckham

[Leif A.]

Re: '67 Battery tray bolts with factory A/C

On a 66 frame they used a threaded insert, like a nutsert in todays world can't imagine 67 would be different. It would be fairly easy to install them and you would be the only one that knows
Bob Peckham

Bob,
I agree that would be a terrific solution...if I could get to that area to drill out the threaded insert and then insert the nutsert. This may have to wait until this fall when the weather cools down and I can get the car on a lift, remove the splash pan and see what kind of access I have to those holes. I was looking for an "easy" way out but there doesn't appear to be a way...imagine that

[Larry M.]

Re: '67 Battery tray bolts with factory A/C

Leif:

These bolts were originally threaded directly into the frame. Obviously a poor design. I would use threadserts to repair. This is what JohnZ (RIP) recommended as well.

Larry

[Gary B.]

[Peter M.]

Re: '67 Battery tray bolts with factory A/C

Leif,
Remove the bolt and fold a piece of small diameter wire in the hole, then reinstall the bolt. This should allow you to tighten up the bolt.
You may have to experiment with wire diameter.
Kind regards

[Mike B.]

Re: '67 Battery tray bolts with factory A/C

I'm with Larry on this one. These self tapping screws with their separate special thick washers were originally threaded into the frame. Lots of other threads written on this subject. There have been a mix of coarse or fine thread screws reported for '66. Prior to '66 mainly fine thread screws reported. But the '67 usually shows the coarse threaded screws.

GM Engineering Specifications for screw #9422606 shown in the '67 AIM UPC C60 sheet E2 are for a Hex Head, Type C, Tapping Screw, 5/16 - 18 x 3/4", Phosphate Coated part. Here are a few photos of an original found on '67 VIN #14,0XX's AC battery tray. An L36 coupe.

Mike

'67 VIN 14,0XX AC Battery Tray Screw (1).jpg'67 VIN 14,0XX AC Battery Tray Screw (2).jpg'67 VIN 14,0XX AC Battery Tray Screw (3).jpg

[Mike B.]

Re: '67 Battery tray bolts with factory A/C

Here are some shots of a partial set that I purchased a while back. The exact same screws.

Mike

'67 AC Battery Tray Screws (1).jpg'67 AC Battery Tray Screws (2).jpg'67 AC Battery Tray Screws (3).jpg'67 AC Battery Tray Screws (4).jpg

[Leif A.]

Re: '67 Battery tray bolts with factory A/C

Mike,
Thank you for the pictures of the original bolts and the description of how they were originally installed.

[Mike B.]

Re: '67 Battery tray bolts with factory A/C

You're welcome Leif,

I'm quite certain that the example "E" screw shown in post #10 is original to that car. Others may exist but so far that's the only head mark I've seen for a '67. It would be great once again for folks to post what was original to their C2 AC cars.

Cheers, Mike

[Gary B.]

Re: '67 Battery tray bolts with factory A/C

I think I finally understand the disagreement about the battery tray bolts and frame holes. On non-AC cars with the RH battery location, the battery tray fasteners are GM 3719206. In the AIM that fastener is described as a “SCREW ASM”. The ASM descriptor indicate those screws have a captive (lock) washer. And those screws have regular threads, not self-tapping. Those screws thread into some sort of thread inserts that are integrated into the holes in the frame. Those screws are used in combination with the plain washer GM 3728666.


On cars with C60 with the LH battery location, the battery tray screws are GM 9422606, which are described as a “SCREW” (not a SCREW ASM), and they are paired with the plain washer 3728666, which is a loose washer. It must be the case that the LH battery tray holes in the frame do not have any thread insert, and self-tapping screws are needed to create the threads in the frame.

Gary

[Mike B.]

Re: '67 Battery tray bolts with factory A/C

You're absolutely correct Gary. And as Larry stated, the AC battery tray tapping screw setup is a poor design. Some of my frame holes are elongated/stripped. My car had 5/16 - 18 X 3/4" screws installed when I bought the car in 1988 but I don't think that those were original to my car. They have a flanged lip on the screw head.

A good friend who's AC L36 '66 is just 600 cars after mine has original 5/16 fine threaded screws with typical "D" head marks surrounded by a 3 ring bullseye. I bought a set of originals like his screws and now I'm gonna have to figure out how to install the fine thread screws in the old holes. I like the threadserts idea for a repair.

Mike