Transmission tunnel boot/seal position for M20 install

[funkyscooter]

Tidying up the transmission tunnel on O'Rusty. Need advise/ confirmation as to how the the gear shift boots should be mounted to the tunnel. Here's an exploded drawing from a HZ parts manual.

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So there is 12 - floor pan boot, 11 - Floor pan boot retainer, 8 - Seal, and bolts SP 2211.

As I can see no nut, do I assume that the lot is held down with captive nuts in the floor pan? So floor pan, seal, boot, retainer. All on top of the tunnel.

That kinda makes sense. Previously the lot was screwed into the tunnel with metal self tappers. Looked pretty dodgy and the seal was barely held in place and was not living up to its name. Here's the neat hole they cut. I can only assume that it was reshaped after the gear stick was installed.

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Here is what I knocked up thinking I was just doing a simply tidy up. This covers the existing self tapper screw holes so I though all good.

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Then I dragged the gear stick out and that's when I saw the seal and the 4 big holes. No way my metal is going to work, as I have made the hole too large.

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Going to buy a new seal/boot/retainer when I have enough on my wish list to make the postage reasonable and re-fabricate the tunnel to suit that. Will also put the gearbox in as I think the tolerance will be reasonably tight if the seal is bolted on correctly.

For now, another piece of metal thrown in the corner.

[EK283]

I have never used the bottom rubber seal and quite frankly I didn't even know they existed !!!

Screwing the top boot rubber down on top of the carpet with self tappers was the norm back in the day, although in saying that the hole according to NCOP should be strengthened so you could use that piece you made and weld on top of the hole.
That then gives you some metal for the self tappers to bite into without stripping or you could tack some nuts on the underside and use some small bolts.

Plenty of options there.

Greg

[Blacky]

Easiest option would be to get yourself a rivnut tool and use rivnuts, they sell kits on Epay
https://www.ebay.com.au/itm/Nutsert-Too ... %3A2334524

[funkyscooter]

Greg - pretty sure the bottom boot was just floating underneath, and the top was screwed. The bottom boot was filthy with oil blown back off the engine. For that reason I can see it has its purpose to minimise dust, fumes and maybe a bit of noise. Not too expensive, but might be a pig to fit correctly.
Blacky - definitely got a rivnut on the tool purchase radar!