Recently whilst driving the Barracuda (/6), I’ve heard a little putt-putt-putt on acceleration, though not when the car is moving slowly or stationary with the engine running. This tells me there is a small hole in the exhaust somewhere.
The exhaust system itself came from Pipecraft in Essex in the late nineties and I had difficulties in fitting it properly---it was impossible to position it so that it didn’t bang against the prop shaft on occasions! In 2003 when I had the engine taken out for overhaul, the guys who did it had similar problems with the exhaust after replacing the engine. What they did was cut out certain sections of the pipe and re-weld other sections in so that in effect I had a continuous exhaust. I suspect that one of these welds may have perforated, though lying on the ground with a torch, I can’t see any evidence of smoke deposits. I’m sure that with a garage’s hydraulic lift, as at the next year’s MOT, the fault would become visible. But if I leave it till then, I’ll only have a couple of weeks afterwards to get it sorted. I doubt if my MOT man would allow the traditional trick of exhaust bandage under a Jubilee clip.
Clearly the local quick-fit exhaust shops have no interest in servicing what is essentially a custom exhaust and the place where my “continuous” exhaust was fitted sold up for housing several years ago.
Are there any members who can recommend a proper exhaust shop with pipe-bending facilities in Surrey that could weld in a new section wherever it’s needed? Or should I be considering getting a stainless steel exhaust made up? I’ve heard that though they don’t rot, they can crack and so the cost benefit is debatable. If that IS the suggested course of action, again, is there any recommended outfit in central Surrey?
Exhaust dilemma
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Exhaust dilemma
1969 Valiant Barracuda (/6 from South Africa)
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- Posts: 1667
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- Location: Alicante Spain
Yes, I'd thought about the vulnerability of the exhaust manifold! However it is the fully ribbed sort with the circular counterweight on the heat riser valve so it should be less resistant to cracking. I replaced the original 1969 manifold with a later one when the engine was out, which needed a bit of alignment (grinding) at a machine shop. Anyway, it was a perfect fit thereafter.
With the hood up and engine running I can't hear this putt-putt-putt against the engine whirring. Holding my hand around the manifold I can't feel any small jets of escaping gas because the fan is blowing so much air around! I don't know if there'd be deposits of anything around the flange if it weren't sealing correctly but anyway, I can't see anything. The sound, when I'm accelerating, is definitely forward of the driving seat, though, not behind, as in the muffler.
Perhaps I should wait until the problem (if it is one) gets worse and identifies itself more specifically.
With the hood up and engine running I can't hear this putt-putt-putt against the engine whirring. Holding my hand around the manifold I can't feel any small jets of escaping gas because the fan is blowing so much air around! I don't know if there'd be deposits of anything around the flange if it weren't sealing correctly but anyway, I can't see anything. The sound, when I'm accelerating, is definitely forward of the driving seat, though, not behind, as in the muffler.
Perhaps I should wait until the problem (if it is one) gets worse and identifies itself more specifically.
1969 Valiant Barracuda (/6 from South Africa)
- Johnny Dart
- Posts: 852
- Joined: Tue Dec 24, 13 12:46 pm
- Location: East Sussex
is definitely forward of the driving seat, though, not behind, as in the muffler.
Perhaps I should wait until the problem (if it is one) gets worse and identifies itself more specifically.[/quote]
Get your mates/passers by ,to put there hand over the end of the exhaust pipe ,engine running, while you listen to where the gas is escaping.
easy
Perhaps I should wait until the problem (if it is one) gets worse and identifies itself more specifically.[/quote]
Get your mates/passers by ,to put there hand over the end of the exhaust pipe ,engine running, while you listen to where the gas is escaping.
easy

GJUK, Funny you should say that because only this morning (and before I read your post!), I had a man with a stethoscope help me trace the root of the problem.
It isn't the manifold cracking (relief!!!) or an exhaust pinhole after all. It's the choke well cover.
My carb was converted to manual operation back in RSA and there's a well-shaped blanking plate bolted to one limb of the exhaust manifold where the choke used to sit. The sealant around one side of this had blown out.
I don't intend to remove the plate to replace the sealant because no matter how much WD40 I drained in, there's still the danger that a bolt might shear off and then I'd really be stuck! So I'll just poke Gun-Gum or whatever similar I can find in my garage into the gap with a penknife, then let the exhaust harden it off.
It isn't the manifold cracking (relief!!!) or an exhaust pinhole after all. It's the choke well cover.
My carb was converted to manual operation back in RSA and there's a well-shaped blanking plate bolted to one limb of the exhaust manifold where the choke used to sit. The sealant around one side of this had blown out.
I don't intend to remove the plate to replace the sealant because no matter how much WD40 I drained in, there's still the danger that a bolt might shear off and then I'd really be stuck! So I'll just poke Gun-Gum or whatever similar I can find in my garage into the gap with a penknife, then let the exhaust harden it off.
1969 Valiant Barracuda (/6 from South Africa)