Page created: 7-Jun-06

Re-published: 1-Nov-09


Rock Sliders

Technical: Discovery I
Discoparts Rock Slider Installation

When I collected these new rock sliders the first thing I noticed was that they were heavy, which I guess is the price you pay for something that's substantially constructed and has extras such as 'tree bars'. Unlike my old Terrain Master guards, each Discoparts guard is one complete unit, requiring no further bracketry and only a selection of long bolts, which were supplied, to complete the kit. 

The inside of these guards comprises a channel of 5mm thick steel, which is designed to fully enclose the vehicle Discoparts cill guards awaiting installationbody cills, with cut outs only to clear the door pillars. The guards are then fixed with the bolts through pre-drilled holes in the sides of the channel and right through the body cills, for which new holes must be drilled. 

As the whole point of removing my old guards was to carry out rust proofing, I decided to position the new guards and drill all of the holes first, then paint the cills before the final fitting. It was at this point that I came across my first problem. In order to drill the holes I needed to mark where they were needed, which in turn meant first positioning the guards. I then discovered that none of the jacks that I had available would lift them high enough so various bits of timber were pressed into service to make up the height difference.

First guard in position on jacksThe bottom of the body cill isn't flat - there's a projecting seam that runs the full length - so there's a degree of juggling required to get the guard in the correct position. I was aiming for having them pressed as tightly as possible to the underside of the body cill, but it's also nice to still be able to open the doors so a compromise was reached after much fiddling with the jacks. With the first guard temporarily in place I then proceeded to drill the holes, which is when I came across my second problem.

Some of the required holes are easy and it was just a case of offering up the drill and away you go. However, the positions of some mean that it's impossible to get a drill in the right place without removing the doors! Also, as it's very difficult to drill a hole through both sides of a 75mm body cill and have the drill come out in the right place, it's necessary to drill from both sides. However, the inside of the body cills are no better as there were more obstructions in the form of various chassis and suspension bits. This, as you can imagine, was more than a little frustrating.

Fisings inside rear door cillFixings inside front door cill







I eventually worked out that I could probably drill the holes if I had a right-angled drill head and so spent a frantic Elusive right-anged drill headhour trying to track down such a thing in the various tool and hardware shops in the surrounding area, which I fortunately did manage to do. This helped a lot and allowed several more holes to be completed, although there were still a couple that were proving difficult. I eventually gave up on these all together.

With all the holes I was likely to achieve now drilled, I set about my original task of rust proofing. Firstly, I drilled some larger holes in the bottom of each cill and used a drain cleaning attachment on my pressure washer to clean out the insides. I was surprised just how much muck came out, including a reasonable quantity of Sahara sand! 

Generally though the cills really weren't that bad so I lightly rubbed them down, including the front part of the rear wheel arches, and first gave them a coat of Unidox zinc rich primer before finishing with Smoothrite. 

Cill with holes drilled and primer applied

I was originally going to use black enamel Supacote for the finish until I discovered that Smoothrite was available in a dark red that was a pretty close match for the vehicle colour.

Painted prior to final fitting of cill guards

Waxoyl warming up in hot waterFinally, I pumped in a large quantity of Waxoyl, which I warmed up by standing the tin in a bucket of hot water, and also sprayed the underside of the rear wheel arches and inside the door pillars for good measure.

After all that, it was a relatively straightforward task to offer up the guards again (with the jacks and the bits of timber) and inserting the bolts. I remember that when I first looked at these guards I was concerned about the possibility of crushing the body cills with the long through bolts, but in practice the steel channel of the guards is so robust that it's very difficult to apply enough force to make it deflect significantly.