Seat Frames, Series 3, IV, & V

[Alpine Bob]

I have several later seats. I'm trying to pair them up and get one good set, but I don't know the differences between them. I believe the 3s and the IVs are the same and the Vs are different. Tigers come in the mix somewhere too.

 

[nickraymond]

Aren't the series V seats split into three sections and the series 3 and 4's two?

I'm not sure to be honest but I know its something like that that's different on the 5's.

 

[alpine_64]

Bob,

All the frames should be the same, the difference is in the foams, vyinl trim and the cushioning.

The S3 and IV had a floating backrest panel (and early series 3's had a split thigh support too) these earlier seats also used a pirelli webbing under the seat cuhion the later steats have a rubber diaphram. The early setas have several larger horizontal pleats in the seat and base.. the SV's have a single peice rear seat with smaller horizintal ribbing on both base and backrest.. i can link you to photos if that will help.

 

[Alpine Bob]

I was ordering the diaphrams for the seats and Rick asked me what seats frames I had, I had no idea. I'm not worried what the covers look like, I just need to know what the difference is in the frames. In Ricks (Sunbeam Specialties) catalog he shows a diaphram for the series V, and strapes for the 3 & IV seat bottoms, that's where my delima come in.

 

[sunbby]

Here are some pics of my Series V seats. The diaphragm connects with little hooks into small holes on the frame. There are 3 on each side, 3 on the front and 2 in the back. I'm not sure how the Series 3 and IV attach, but if yours don't match mine then they're not Series V. Also note the holes on the sides are underneath, so the hooks go up into them, while the fronts and back are on top, the hooks go down into them (hope that makes sense.)

 

[ALC 68A]

You may already have solved this problem, but I have only just seen your post. Having just repaired my series 3 seats, I can confirm that they are different from the Series Vs. AFAIK all 3s have the seat base and backrest in three parts - the side bolsters and the centre panels are all in separate sections. The support to the centre cushion is provided by crosswise rubber straps which attach to metal hooks. The bottoms of each side bolster are made of a strong cloth with a pocket in it to hold a metal strip. This strip has holes in it for the ends of the metal hooks to locate into. The tension in these straps pulls the upholstery together.

The main difference between the 3 and the V is that the V has a section of frame across the front of the seat to take the hooks to support the rubber diaphragm. This isn't there on the 3, so you can't use the V diaphragm. I think the series IVs have a similar construction to the 3, except the seat cushions and backrests are all in one piece - they certainly use the same type of support straps.

The original straps were made of rubber with metal ends bonded in, but on all the ones I have had, the straps have perished and broken. However, you can buy a woven stretch strapping from an upholstery shop which does the job just as well, although it does look different, so might lose you some concours marks. It comes with toothed metal clips which you clamp on with a vice after cutting the strapping to length (allowing for a bit of stretch). I was told it is better than Pirelli webbing as it lasts longer (and it's cheaper - at least in the UK).

I was lucky with my 3 - the upholstery was in saveable condition, so with new foam and straps the seats are now comfortable again. Much cheaper than paying for a complete recover, and more original as I don't think the proper GT type leather cloth is still available.

Steve