Sunday, June 03, 2018

We always hated prop rods for various reasons, hands were full, rod is in the way to do engine maintenance and so on. Jeffrey had eliminated that problem on his 1995 Subaru Impreza by adding rear hatch gas shocks to the hood with great results, so he wanted to do something similar for the CJ. Mainly because he didn't like laying the hood back against the windshield and didn't want to mess with a prop rod. Now we were told by several sources that gas shocks are not recommended for fiberglass hoods for the simple reason that since no mounting supports were glassed in during construction that if done later they would eventually crack and break out. Rough Country makes a nice setup for the TJ.
A couple of ball studs McMaster Carr part number 9512K98 were ordered and fastened to split collars. The collar would temporarily allow us to move the location of the stud on the grille rod for optimum position. Now came the hard part. selecting a gas shock with the right length and pressure to lift the hood. I found several gas shock sights that gave formulas to calculate pressure, but the answers greatly varied due to the fact that we were also angling towards the center of the hood. So I devised a method to determine how much force was needed to keep the hood open. I took a length of 1" pipe and welded on an eye hook to fasten to the grille rod, and put several springs inside of it. Then a length of round stock that slid into the pipe 
with another eye hook welded to fasten to the hood on a temporary bracket. I kept changing out springs until I got the hood to stay open at the desired position. I then scribed a line around the round stock against the shoulder of the pipe. This also gave me a length that was needed. Taking the assembly off the one end was placed on a bathroom scale and compressed until the mark lined up with the shoulder. The poundage was then read off the scale, which was 41lbs. Formulas say to add 10% bringing it up to 45lbs. I also added some weight to compensate for the weight of Line-X to the underside of the hood. Now using the marks on the hood and grille rod I was able to get a compressed length by partially closing the hood and measure
between the marks. So I ordered a gas shock from Bansbach with a 22" open length, a 10" stoke and a pressure of 58lbs. Whats nice is that you can specify the pressure that you need. I added pressure figuring I could deal with too much pressure rather than not enough. Temporarily mounting everything to the makeshift brackets to see if it all worked, adjustments were made to end link locations to finalize positions and clearances. Once done an aluminum bracket was made and mounted to the sheet metal with 1/4 - 20 flathead screws from behind. for the mount on the grille rod a 1/2" piece of round stock was pressed into the rod after milling a 1/2" counterbore then brazed.
 Then a hole was drilled into it and tapped for the 10mm. ball stud. Lifting the hood now takes very little effort and opens to a convenient position for engine maintenance and most importantly there is no stress on any of the fiberglass.

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