Build 73. Seats

Caterham have changed the way they install the seats and provide black countersunk hex bolts along side some countersunk washers which are used to install the seats from the bottom. This makes installing them easy when there is just one of you. Be prepared to remove them a few times and re-install them as you go along to make sure you get the fit just right.

In order to get mine to fit just right with the right height and angle, I decided to firstly buy a set of Tillet spacers from Demontweeks and then also some longer hex bolts of A4 grade (the length will vary based on your needs but mine only needed to be 5mm longer).

The passenger seat was wholly uneventful, I simply connected the unfinished aluminium metal bars to the underneath of the seat, and used 2 x 10mm spacers (included in the seat fixing pack) + 1 x 4mm space (in the Demontweeks pack to raise it up a bit more for the smaller passengers). I used some Loctite on the bolts and then torqued them up to 14Nm. The seat was then lowered in to place and as I lowered it, I first connected the heated seat cables, and then I fed the lower harnesses through the side parts of the seat. I used a punch underneath to locate the seat in the correct position before using the longer black countersunk screws to fix it in place, again I torqued these to 14Nm and that was 1 seat done!

I can confirm that my car passed the PBC with the countersunk washers on the underside, so this should be the preferred way to install your seats.

The drivers seat was a bit more complex, I think I ended up taking it out 4 or 5 times to get it right, each time I noticed something different:

Firstly, it is on runners, and having used carpet and Duramat beneath meant that the first time I tightened it up, the runners failed to even move.

Secondly, this initial fit also showed that I needed to bend the lever so it would fit through the hole in the lowered floors, otherwise the lowered floor chassis bracket gets in the way of the runners.

Thirdly, the seat was fouling on the outside rivets of the car, so would need tilting to avoid this.

With the above in mind, this is what I ended up doing to get the driver seat in place.

• Bent the lever downwards, I simply put it in the vice and bent it from there, I also needed to bend it a little more once it was in place but this was done by bending it over a socket piece.
• On the side that was fouling the rivets I raised it by 4mm (using a 4mm Tillet spacer on each bolt) this was done where the seat attaches to the runners.
• I also used a 2mm spacer between the runner and the floor at the rear, and then used a 4mm spacer at the front to tilt the seat a little. This also kept the runner off the floor so it would slide well.

Once I was happy with all the bolts underneath, I one by one removed them, put some Loctite on them, and then tightened them back up again (to 14Nm)

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