Author Topic: bang pop bang  (Read 1817 times)

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Offline tck

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bang pop bang
« on: 03 Apr 2014 at 06:33 »
I have an early T35 with a waffle box ,its time to fettle it for the season . one thing annoys me is the popping and banging on the overrun. When I get her on the ramp I shall get tooled up with exhaust pipe cement  and shim material but I wonder if there are any tricks of the trade or points to look out for before I start

Offline Ian

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Re: bang pop bang
« Reply #1 on: 04 Apr 2014 at 00:00 »
I don't know the later models and their idiosyncrasies but what you are planning seems normal practice - just did the same thing on my Matchless.

Offline eddie

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Re: bang pop bang
« Reply #2 on: 04 Apr 2014 at 06:32 »
       Popping and banging in the exhaust is usually caused by air leaks either at the cylinderhead or the pipe to silencer joint. This can be made worse if it is accompanied by a rich idling mixture. Also, the original exhaust system had the pipes going into the wafflebox by about 8" - with the last 7" slotted on the inboard side, and the ends blanked off. The original waffleboxes also had another baffle behind the large brass plug (in the centre front of the box). This was in the form of a tube (same diameter as the exhaust pipes) with slots on either side. Often (after 60+ years), all that remains is a rusty ring located in the register in the dividing wall across the box.