s.leah Posted March 11, 2016 Report Share Posted March 11, 2016 What the title says! I've recent received a shiny new gearbox cover from a lovely chap called Nigel via Facebook. Sadly the insulation from my old cover has, like the old cover, expired Any suggestions for replacement? I've got some silverbacked loft insulation on a small roll booting around. I assume that would work for the actual padding, but what would be best to put it in? I'd have though the temperature would be too high to just 'modify' a rubble sack or thick black bin bag? I haven't actually tried to be fair.... Also would carpet glue be OK to attach whatever I use to insulate or would I better with Stixall or equivalent? (Can't staple 'cos it's hard fiberglass) Cheers Simon Link to comment Share on other sites More sharing options...
JohnD Posted March 11, 2016 Report Share Posted March 11, 2016 Simon, That's what Triumph used! Rockwool or similar in a tough plastic sleeve, stapled to the inside of the cover. But FAR more important if you want to keep cool in the car (apart from wearing shades at night) is to ensure that it seals to the bulkhead and floor (Club shop sell seal sets - I din't know how good they are) AND that the many holes in the bulkhead, some that pass wired or cable, some that seem to have no purpose, are sealed. Triumph used rubber grommets, but modern adhesive aluminium tape is easier to fit. See Screwfix, Wickes, Homebase or any hardware store There is a LOT of very hot air under the bonnet, mostly - all! - from the radiator, rushing away under the car and down the transmission tunnel. It will transfer that heat to you if it can get inside far more effectively that radiation from the exhaust pipe and gear box. John Link to comment Share on other sites More sharing options...
s.leah Posted March 11, 2016 Author Report Share Posted March 11, 2016 Thanks John. Yes the old stuff was stapled in, but as I say stapling isn't an option on the new cover. So it sounds like my spare loft insulation and a rubble sack is the way forward Probably go with Stixall to glue, or copious amounts of Evostick, Mmm..... LOL Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 11, 2016 Report Share Posted March 11, 2016 "apart from wearing shades at night" Have you seen the price of Ray Bans these days?!! (I wonder if the club shop could be persuaded to stock them?) Sorry for thread drift but I notice my steering column goes through a VERY large hole in the bulk head, the diagrams on Canley show a couple of washers which I think means the column has to be disconnected to get them in. Is there another solution? Link to comment Share on other sites More sharing options...
Pete Lewis Posted March 11, 2016 Report Share Posted March 11, 2016 Another alterative would be sealed cell foam easy to cut and stick was a std noise heat insulation in the old days seen it at autojumble sales theres lots on line , has a sealed suface to stop absorbing oils or fuel on the Vit 6 we used sealed coated needle loom felt about 25mm thick. worked well evo sticked to a fibre glass tunnel pete Link to comment Share on other sites More sharing options...
Colin Lindsay Posted March 12, 2016 Report Share Posted March 12, 2016 Go to a local scrappie and get modern car sound or heatproofing; many just throw it away so it sells for pennies. Waterproof and heatproof and easily trimmed. The more modern the car it comes from, the better it should be... so look for a good recent accident damaged model to pinch it out of. Link to comment Share on other sites More sharing options...
Steve C Posted March 12, 2016 Report Share Posted March 12, 2016 You can rescue the original soundproofing simply by binning the old (usually torn / damaged) polythene and re-wrapping it in some new polythene sheet, which is sold by garden centres for peanuts, and is on every farm and market garden. I used an ordinary stapler to seal the edges. Rather than glue, which has a habit of drying out, I used twist ties, through 1/16 holes drilled in the cover, to fix it at key points. This has held up well on my Herald for five years now, and cost me almost nothing. Regards Steve C Link to comment Share on other sites More sharing options...
JohnD Posted March 13, 2016 Report Share Posted March 13, 2016 Doug, The seal is in two parts, wit a metal pressing as retainer. Cut the seal in two parts and the retainer the other way, to get them off and on without removing the column. And, what price style, man? And, Pete, Colin Steve, are you stuck in the Ice (or in this case, Tropical) Age? Foam rots, especially when heated and exposed to hydocarbons, used heat proofing originally shaped for a completely different car, and fixation of heat-proofing itself. How many times, how loudly can I say, IT'S LEAKS THAT CAUSE EXCESS HEAT! Sorry to shout, but my own experience, and even better the Silverback experiment, showed this conclusively. Adhesive aluminium foil is what is used in motorsport and in production these days to seal unwnanted holes, Why use enything else? John Link to comment Share on other sites More sharing options...
Colin Lindsay Posted March 13, 2016 Report Share Posted March 13, 2016 Doug, The seal is in two parts, wit a metal pressing as retainer. Cut the seal in two parts and the retainer the other way, to get them off and on without removing the column. And, Pete, Colin Steve, are you stuck in the Ice (or in this case, Tropical) Age? Foam rots, especially when heated and exposed to hydocarbons, used heat proofing originally shaped for a completely different car, and fixation of heat-proofing itself. How many times, how loudly can I say, IT'S LEAKS THAT CAUSE EXCESS HEAT! Underbonnet heat shield panels from modern cars aren't foam; they're usually some form of composite - don't ask me which exactly - but many come as a flat panel attached to the underside of the bonnet by plastic studs. Easy to remove, trim and mould over the gearbox tunnel; not to an exact moulded shape but still close enough to replace the carpet and not notice that it's there. The carpet and some adhesive holds it in place. I put my hand on my gearbox tunnel and it's warm through the existing material, so that's not a leak, it's conduction? Warm air blowing through gaps under the tunnel cover will get hot air into the cabin as you say, but anything else that can be removed from the equation can only be a bonus, especially when stationary in traffic. Why use anything other than adhesive silver foil? Because it's ******** expensive and anyone on a lower budget might be looking for a cheaper, and almost as good, option. I can only suggest a few alternatives... Link to comment Share on other sites More sharing options...
DerekS Posted March 13, 2016 Report Share Posted March 13, 2016 Frost do a very effective rubberised soundproofing felt which resists oil splashing to a certain degree. They also do a very useful high temperature contact adhesive which I would certainly recommend. I've covered my g/box tunnel both sides with the felt and the results really are superb. I also have an access panel for the g/box filler but that's another story. Incidentally, the heat intrusion is a big downside of using fabricated exhaust manifolds, I got shot of the one on my car as it wasn't too bad in Winter but Summer days the heat was unpleasant. Again, depends what you want. Link to comment Share on other sites More sharing options...
JohnD Posted March 13, 2016 Report Share Posted March 13, 2016 Now you blame "fabricated manifolds". Listen to me! Silerback was the only Triumph in history to have a rear radiator, and it was also the coldest in history. NO heat from the gear box, NO heat from the exhaust pipe, NO heat from its fabricated 631 manifold, NO heat from the 2.5L engine and NO bloody heat from leaks in the bulkhead. ALL the heat under the bonnet is from the radiator, via hot air getting into the cabin. Seal all those holes and you'll stay cool, NO need to get fancy with exotic insulators. John Link to comment Share on other sites More sharing options...
DerekS Posted March 13, 2016 Report Share Posted March 13, 2016 Sorry if I've just given the impression that I hadn't read and digested what you say regarding sealing holes. You are, of course, perfectly right; there was an excellent article in Practical Classics magazine within the last 2 years about it. Sealing gaps and even tiny holes eliminates a lot of various noises. BUT, mine WAS sealed, believe me! Link to comment Share on other sites More sharing options...
dougbgt6 Posted March 13, 2016 Report Share Posted March 13, 2016 John, I believe! I will be sealing my holes (insert joke here) but I'm also concerned about noise. I want to hear my burbling exhaust, not under bonnet clatter from tappets, alternator and other worn out mechanicals. Link to comment Share on other sites More sharing options...
Dave C Posted March 13, 2016 Report Share Posted March 13, 2016 I've done both holes and gearbox tunnel insulation. I've also done sound deadening. John is correct in my opinion; the single biggest contributor of cockpit heat in my car was holes in the bulkhead and ill-fitting gearbox tunnel. Doug and others are also correct in my experience that insulating the gearbox tunnel has further reduced heat transmission, whatever the source is. I fitted heat resistant ceramic matting which also has foil on one side, which i purchased from a kitcar supplier. I glued it to the tunnel using heat resistant contact adhesive. I used 'Silent Coat' sound deadening panels which seem to have done the job well. I can still hear the engine and the exhaust just fine, but it's no longer like sitting in an oil drum. Link to comment Share on other sites More sharing options...
JohnD Posted March 13, 2016 Report Share Posted March 13, 2016 Noise, don't talk to me about noise! There are 90+ decibels in the cabin of SofS at full chat - I've measured them! John Link to comment Share on other sites More sharing options...
s.leah Posted March 14, 2016 Author Report Share Posted March 14, 2016 I've done the job now. I went with the loft insulation, thinned down a bit as it was too thick! I wrpped it in a rubble sack and carpet glued to the underside of the tunnel. I figured it's not going anywhere once in position so nothing stronger needed. The insulation came 'wrapped' in plastic which was just plain old plastic on one side and silvered on the other. I cut the silvered side off and glued that to the gearbox-facing side of the insulation to offer some heat reflection. I just used draught excluder to seal the cover to the body tub and put some new self-tappers in to hold it all down. Looks neat and fits very snuggly. Time will tell how well it has worked! A short 3 mile run to get it to temperature and I wasn't aware of fumes or flames or dry roasted shins, so far so good Link to comment Share on other sites More sharing options...
chrisbladen Posted June 14, 2020 Report Share Posted June 14, 2020 On 14/03/2016 at 10:47, s.leah said: I've done the job now. I went with the loft insulation, thinned down a bit as it was too thick! I wrpped it in a rubble sack and carpet glued to the underside of the tunnel. I figured it's not going anywhere once in position so nothing stronger needed. The insulation came 'wrapped' in plastic which was just plain old plastic on one side and silvered on the other. I cut the silvered side off and glued that to the gearbox-facing side of the insulation to offer some heat reflection. I just used draught excluder to seal the cover to the body tub and put some new self-tappers in to hold it all down. Looks neat and fits very snuggly. Time will tell how well it has worked! A short 3 mile run to get it to temperature and I wasn't aware of fumes or flames or dry roasted shins, so far so good Hi mate, i know its been a while since you posted this thread but im just curious at how your solution panned out? I was thinking about doing the same as you in regards of sealing and using draught excluder. In regards to insulating the tunnel i was planning on using some 5mm aluminum backed heat proofing which apparently has a temperature resistantance range up to +149°, which i am a bit sceptical of lol. Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 14, 2020 Report Share Posted June 14, 2020 Chris, Along with others I’ve used stuff called SilientCoat, bought on EBay, ali on one side sticky sound/heat insulation on the other. Works very well. I got a new poly tunnel which came with a seal too shallow for the job, so added a length of ordinary draught excluder. Also works very well. Doug Link to comment Share on other sites More sharing options...
chrisbladen Posted June 14, 2020 Report Share Posted June 14, 2020 Ta doug. My original tunnel is looking a bit tired and has a bit of damage, its repairable but i was thinking about going for a fibreglass replacement. Is there any other reason to replace it, other than if the original was beyond repair? Do the repo's give a better seal or anything? Link to comment Share on other sites More sharing options...
NonMember Posted June 14, 2020 Report Share Posted June 14, 2020 If the original is good then it's generally better. The repros are more waterproof but thinner (poly) or too stiff (GRP) and generally don't fit nearly as well. Link to comment Share on other sites More sharing options...
dougbgt6 Posted June 14, 2020 Report Share Posted June 14, 2020 Chris, My original was falling to bits so it had to go. I put the SlientCoat on the inside of the poly replacement so thinness wasn't a problem, however there was a lip all around the bottom and the front which made the supplied gasket too shallow. I added a length of draft excluder, but others have ground 1/4" off the lip. Some people have had a problem with the hole for the gear stick being in the wrong place on the cover for Vitesses or Heralds (I think?) I cut out an access port in the side, which allowed me to top up the gearbox oil without taking the cover off. Doug Link to comment Share on other sites More sharing options...
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