The Triumph Dolomite Club - Discussion Forum

Hi all. I am sure this has been covered many times before, but does anyone have any recommendations for sealing a gearbox tunnel?

I've removed mine to deal with some grot (caused likely by the seal failing in the first place), so after I have cleaned it all up and dealt with the rust I will want to seal it properly.

Any ideas much appreciated.

Kind Regards

MC

I bought this for my Toledo, but it's going to be some months before I try it:

https://shop.tssc.org.uk/product/gearbo ... l-seal-kit

I didn't measure to see if 3m was long enough!

I don't think the fixing are any good, but hopefully the seal itself will be.

Matt Cotton wrote: ↑Mon Sep 24, 2018 9:04 pm Hi all. I am sure this has been covered many times before, but does anyone have any recommendations for sealing a gearbox tunnel?

I've removed mine to deal with some grot (caused likely by the seal failing in the first place), so after I have cleaned it all up and dealt with the rust I will want to seal it properly.

Any ideas much appreciated.

Kind Regards

MC

What you need is dumdum sealant, but they stopped making it. Basically a flexible sealant that doesn't set.

I am going to try a couple of strips of universal weather seals on mine, to see if they will work.

As my Sprint is ostensibly a racer it is stripped bare inside. I have used a type of draught seal tape that is adhesive on one side.

I have been to quite a few very wet events this year, namely Croft at Easter during the Beast from the East and later at 3 Sisters where I was literally going through water splashes.....as there's no carpet I can see if any water comes in....result, no leaks!

Something like this....

https://rover.ebay.com/rover/0/0/0?mpre ... 2385847929

Old fashioned windscreen sealant, still available from motor factors, in plastic tubes. It's pretty much non-setting.

Silicone sealant or butyl strip. The strip though is quite messy to remove if you need to whereas silicone sealant often peals away quite nicely.

I used a neoprene sponge which is waterproof when compressed, roughly 15mm thick from Ebay.

The self adhesive was not doing a good job, so a bit of glue and some bulldog clips helped stick it down overnight.

The picture was taken after removing the tunnel to change a O/D switch, and put back with no extra works to the strip.

The neoprene foam idea is spot on. I think I might go with that.

cleverusername wrote: ↑Mon Sep 24, 2018 10:52 pm

Matt Cotton wrote: ↑Mon Sep 24, 2018 9:04 pm Hi all. I am sure this has been covered many times before, but does anyone have any recommendations for sealing a gearbox tunnel?

I've removed mine to deal with some grot (caused likely by the seal failing in the first place), so after I have cleaned it all up and dealt with the rust I will want to seal it properly.

Any ideas much appreciated.

Kind Regards

MC

What you need is dumdum sealant, but they stopped making it. Basically a flexible sealant that doesn't set.

I am going to try a couple of strips of universal weather seals on mine, to see if they will work.

There is panel sealant which comes as a tape - a modern version of dumdum

I would have thought that something modern like Sikaflex 512, Tiger Seal or butyl rubber caulking strips would outperform that old Eldro Dumdum stuff anyway.

Galileo wrote: ↑Tue Sep 25, 2018 5:46 pm I would have thought that something modern like Sikaflex 512, Tiger Seal or butyl rubber caulking strips would outperform that old Eldro Dumdum stuff anyway.

I don't know anything about Sikaflex 512 but I wouldn't use Tiger Seal - you want to get the tunnel off now and then!

Oh yeah, good point! Forget those first two then, seal really well, permanently... A non setting mastic such as a poly butyl rubber caulking then, I've used IDL99 on my boat windows and deck, definitely waterproof and flexible.

Spot on gents, thanks for the replies.

These all look like viable options and I will look at a 'Dum Dum' equivalent or the neoprene option.

Cheers.

MC

I used this:-

http://www.jamespaddock.co.uk/gearbox-tunnel-seal-3

I went through this a few weeks ago, butyl strip was recommended by a member and this I used. 8mm strip, on a roll, warm it up it goes nice and soft, I then bolted it down with 6mm nuts and bolts for added strength. The strip takes up all the varying gaps around the tunnel and never sets so can be easily removed.
I did get some rolls of neoprene foam but found this a little tricky on the varying bends plus then adding all the bolt holes, I did however use the foam on the straight bits at the very top front.

Hope that helps.

Got the butyl from eBay, the branded one in a yellow box if you search.

Chris.