+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: Exhaust "popping" on overrun? (/showthread.php?tid=2763)
Exhaust "popping" on overrun? - Joe eck - 07-05-2019
Having only recently starting using my mk2 Ruby on longer runs after a long restoration, I have noticed that it sometimes pops from the exhaust on overrun.
The car runs very well, the timing appears to be about right ( electronic ignition so difficult to set bang on ? ) and the mixture may be a little rich.
Is this normal and, if not what action is recommended ?
Thanks
Joe.
RE: Exhaust "popping" on overrun? - Ruairidh Dunford - 07-05-2019
You may have a slight induction leak, possibly on the carb or inlet flange.
RE: Exhaust "popping" on overrun? - Joe eck - 07-05-2019
Thanks Ruairidh.
I did check the carb flange for flatness and the carb spindle is as new but I will double check to see if I have missed anything.
The popping is only slight and is probably at its worse when the engine is not fully warmed through.
I have spent many hours tracing and rectifying the sources of rattles and bangs on my car and it is now "almost" on the verge of sophistication !!!
Thanks again
Joe.
RE: Exhaust "popping" on overrun? - Hedd_Jones - 07-05-2019
my daughters RP does it if you lift off instantly while pulling hard. Its excellent for putting the wind up cyclists riding 2 abreast when you overtake. Just lift off the throttle and it. Goes 'pop. pop' with the occasional muffled 'bang'.
RE: Exhaust "popping" on overrun? - Ian Williams - 07-05-2019
If you do not find an air leak I would suggest you look at the timing and the advance curve of your distributor.
RE: Exhaust "popping" on overrun? - David Witton - 07-05-2019
Joe check that you don’t have an exhaust leak between manifold and silencer. It can have the same effect
RE: Exhaust "popping" on overrun? - David Stepney - 07-05-2019
I recently had the same sort of problem with my RP. Tightening the manifold to downpipe flange cured it.
RE: Exhaust "popping" on overrun? - Hedd_Jones - 07-05-2019
my issue is the throttle spindle
RE: Exhaust "popping" on overrun? - "Slack Alice" Simon - 08-05-2019
On mine, if I rev it and then go to maximum retard as I lift off I can get a lovely loud BANG! from the exhaust.
Naughty, but a real head turner, used in the right place.
RE: Exhaust "popping" on overrun? - Hedd_Jones - 08-05-2019
Ken Fox does that with his Indians on the wall of death