c2 battery tray securing bolts

[frank clark]

I am working on a 66 with air and the left side battery tray.
The battery tray is secured now by 6 5/16" bolts with a thick flat washer. The bolts thread directly into the frame.
Here is my problem. I am reinstalling the battery tray after cleaning this area, charging the battery, and changing the battery terminals. The bolts I have will not tighten up properly. I checked the AIM and the judging guide. The JG says that the tray is held down by six recessed head bolts with thick flat washers. (This is on page 91)
Here is the info I need help with.
1. Is the JG refering to "allen" type head bolts, and if so what size should they be?
2. The AIMS manual does not specify the bolt size but gives the number 9422606 for the bolt. (This is on page F288 of my 1966 AIM)
3. Is there a reference available to use the number given in the AIM and know the type and size of fasteners used?
4. Lastly, if the size of thread used is 5/16" can I tap the existing holes to 3/8" and drive on?
Thanks
Frank

[Stephen L.]

Re: c2 battery tray securing bolts

A "recessed head bolt" is a hex head with the center sunken. An example would be the bolts that hold the hood hinges in place...assuming those are original. 5/16" is the bolt size. Are the holes whallowed out/stripped? If so then you may need to drill to the next size or fill in with weld and start over.
There is no cross reference available for bolt part numbers to sizes that I'm aware of. What happened to the bolts you removed???

[frank clark]

Re: c2 battery tray securing bolts

I have the bolts, they are 5/16" recessed head bolts. The original holes do not have good threads. I will either tap a larger thread size or weld/retap the 5/16" threads. What reference did you use to identify that this car used the 5/16" threaded bolts?
Thanks for your help,
Frank

[Stephen L.]

Re: c2 battery tray securing bolts

You mentioned they were 5/16"

[Randy S.]

Re: c2 battery tray securing bolts

I have the same problem on my 66. I planned on trying JB Weld when I replace the battery.

Randy

[frank clark]

Re: c2 battery tray securing bolts (my solution)

Here's is what I did. I went to Fastenal and bought 5/16" "rivnut" fasteners. They are made of steel, take a .500 hole and provide about 3/8" of good thread depth. These should last forever, but if needed these are replaceable and will never be seen if this car is ever judged.

[John H.]

Re: c2 battery tray securing bolts (my solution)

Frank -

I've used Rivnuts for self-tapping screw hole repairs for years; the aluminum ones are a LOT easier to work with, and all you need to install them is a 5/16" Allen head capscrew, an oily AN washer, and an Allen bit for your impact gun.