Fitting Gen 7 seats into a Gen 5
HOW TO - By Geryatrix.
This is the method that I used to fit the Gen 7 front seats into my Gen 5 convertible. I started by reading the excellent write-up by BenMMellor which can be found here.
The problem that I had with that method was, not being an expert welder, I was afraid of the damage that could be caused by trying to weld inside the car. I sent a while cogitating, as you do, before coming up with an alternative method which allows any welding to be done outside the car after the seats have been trial fitted.
The tools you will need are
- 1 meter steel rule or steel tape.
- Hacksaw or angle grinder with a steel cutting disc.
- Electric drill with a selection of bits 2-10mm
- Centre punch
- Large and small hammers
- Pointed nose pliers
- Selection of spanners
- 8 off. 5mm Flat head machine screws 12mm long
- 8 off. 5mm Nylock nuts.
METHOD
Remove the seats from the car and prepare to remove the two mounting brackets from each seat runner. This is done by sliding the runners as far forward as possible to give access to the rivets holding on the front brackets, turn the seats upright and using a centre-punch mark the exact centre of the domed head of the rivet. Drill into the rivet using a 3mm drill to give easy alignment for a larger drill and to check that you are in the exact centre of the rivet. Then using a 8mm drill, drill down until you reach the surface of the bracket, when the domed head should spin on the end of the drill. The rivet can then be punched out using the centre-punch.
Once this has been done, invert the seat and you will see where the bracket has been spot welded, mark the centre of the spot weld with a centre-punch and drill through with a 5mm drill. With the rivet removed and the spot weld drilled out a sideways tap with a large hammer will remove the bracket.
Repeat this for the rear brackets, which you should find easier as they are held on with flat-headed rivets, so it is much easier to mark the centre of the rivet.
NOTE: Make sure to do all drilling to remove rivets from the runner side as if you drill too far you will only damage the runner, which you don’t need, rather than the mounting brackets which you do need.
Finally measure the runner length, and the distance between the centres of the 5mm holes that held the rivets, as you will need to duplicate these measurements on the Gen 7 runners.
On my seats the overall length of the runner was 360mm
Centre to centre on the rivet holes was 340mm.
Now it is time to prepare the Gen 7 seats.
When you invert the seats you will see that the seat runners are both longer than the original runners and also of unequal lengths.
First remove the brackets using the same method detailed above, but this time drill from the bracket side as any damage from over drilling will be on the brackets which are to be discarded.
It is not necessary to remove the rear bracket from the longest runner as that part of the runner will be cut off.
NOTE: As the runners on the Gen 7 seats have locks on both sides for forward and back movement, it is essential that the runners are aligned when fitting the new brackets. After careful measurement I found that the shiny rivet in front of the rear bracket on the longest runner aligns exactly with the front of the two rivet holes on the rear of the other runner.
Remove the shiny rivet, carefully as you don’t want to damage the runner, and cut off the runner 10mm behind the rivet hole, then cut off the other runner 10mm behind the front of the two rear bracket rivet holes.
Fix the two rear brackets into these holes using the pan-head machine screws and Nylock nuts, inserting the screws from the runner side.
Then measure forward 320mm, or whatever the measurement was taken from your original seats, from the centre of the bolts and mark with centre-punch. Clamp the front bracket with the rivet hole exactly over the punch mark, and measure the distance from centre to centre of the holes that bolt the bracket to the car. Then check on the floor of the car the distance between the mounting holes. It’s an extra fiddle but it’s a check on the final position of the brackets, if you have measured correctly the two measurements should be the same, if they are not the same you can check why before you cut the front of the runners off.
Assuming the measurements are OK then drill through the marked points with a 5.5mm drill and cut off the excess runner 10 mm from the hole. Mount the brackets with the pan-head machine screws and the seat is ready to fit.
When you fit the seats, you may have to tap the brackets round to align them with the mounting holes. Once they are fitted score a line on the bracket against the end of the runner, this will enable you to remove the seat and finally tighten the bolts.
The last job to do is to change the seat-belt clip from the old seats as the Gen 7 seats have a smaller seat-belt fastening. This is very easy to do as the clip is only attached with one bolt.
Toyota fit the brackets onto the runners with a 5mm rivet and a spot-weld so I would recommend that after everything is fitted the seats are taken to a local welding specialist to have either a spot-weld or a mig weld to finally hold the bracket to the runner.
Hope that this will be of some help.
