Hi all, I've had the same problem occur twice now with my TR3 exhaust and I think I may have found something that really works as a solution or alternative so worth sharing. My TR3 had an off the shelf stainless steel exhaust fitted until a year or so ago, it was a horrible crude yoke and I hated it enough to make a bespoke one and replace it. Cosmetics and ground clearance aside the first stainless one was suspended at the rear by a strip of reinforced rubber, 6mm thick, its a fairly common way for a lot of the aftermarket exhausts for the Triumphs to be done, it does the job but its poor enough imo. Anyway it failed and like a Chinese take away the exhaust hung low so to speak, I managed to effect roadside repairs but it cemented the need for change in my mind, another club member told me they had a similar experience with these rubber strips as well. So on the new exhaust I made the hanging brackets to suit proper exhaust hanger rubbers, hung nice, no strain, with the mileage on these cars and the way they are stored you'd think that would be the end of it. Approximately a year, maybe 1000-1200 miles, failed again, see the photos attached, on this occasion I put a large tie wrap on it to get home and take a look at it. I did notice when I was putting the tie wrap on that I could hardly touch the tail pipe of the car, right at the back of the car, that surprised me I must admit, this wasnt after a prolonged high speed run where there was a very high exhaust flow or anything like that, more or less tick over in traffic. I do have the stainless exhaust wrapped back to underneath the drivers seat (keep the footwell cool) and there is an extractor manifold on the car, also very well wrapped/insulated. Stainless does not have as good a thermal conductivity as mild steel and I dont ever remember mild steel exhausts getting that hot so far back along the exhausts so its not mechanically conducted heat, so I think that wrap is very effective and the heat is really being carried far back the exhaust by sustained gas temperatures. Interesting.
Anyway, I didn't want this again so I went searching around, the racing and rally boys who are all using wrapping and ceramic coatings etc to get heat out of the engine bay and further back the exhaust are using silicone hangers. Much higher temperature rating and sturdy for getting hacked around, I fitted one to the rear as per the photos and did over 2000 miles on it in hot weather and some hard driving, not a bother on it. Superb product, I'll use these on everything from now on. Thought it might be useful to someone, lots of us running these stainless wrapped exhausts now with extractor manifolds. As a matter of interest the problem with the rubber seems to be when its used with the hot load in suspension, my middle exhaust mount is an old rubber elecric motor mount with the exhaust as a compressive load, its in the middle so hotter than the back, still no problem at all. Because its in compression rather than suspension?
The silicone hangers are availble in different formats and places, I got these from a German supplier, you know the drill no hassle and no Brexit bullshit! https://www.boost-products.eu/Exhaust-Hanger-rubber-Heat-Resistant. That said turns out Amazon or even TEMU have similar in looks anyway.
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Hi Niall, similar "hanging" system on the later Minis, slightly more crude with two bent pieces circular mild steel, one on the subframe, other on the exhaust box; again using the same type rubber hanger as yours. I too have suffered the embarrassment of a failing rubber previously but remedied the issue by applying a simple cable tie around the offending hanger, as below. Done this on two Minis, one went to Germany last year and is a daily driver, the other like 'little red' also ventured to Northern Spain in May this year and on checking both tonight are still functioning well. They appear to fail in suspension as you mentioned, the rubber aint what it used to be. I think the cable tie allows a some element of support lacking in the original hanger, which now functions well, allowing support but also allowing some movement to the exhaust. Both mine are MS, I think one manifold is wrapped but the ex pipes not, maybe as you say tis the heat which the hangers don't like! Also Cantabria in May wouldn't be as hot as the summer. PiBren
Yeah that's a good idea Bren, I could see how that would work. Cheaper than my solution too!