Backfire on overrun

[James k]

Hi,
I'm getting quite a lot of backfire on overrun, for example when going down a fairly steep hill in third gear. What could be the cause of this and is it typical? I am talking about popping and not the classic Morris Minor overrun noise or exhaust parp.

Thanks,
James

[Myrtles Man]

Leak in exhaust?

[mobylette]

0

[mobylette]

+1 for exhaust leak. Cast an eye over the entire exhaust system and see if you can spot any witness marks to show where exhaust gases are escaping , usually at a joint.

[kennatt]

check the timing probably slightly retarded

[myoldjalopy]

It could be any number of things in addition to those mentioned above - faulty plugs, wrongly set points gap, failing condensor, weak fuel mixture, sticking valves......to mention just a few. Are all leads and connections on the ignition system secure? Have you altered/adjusted/changed anything recently - which might be a clue?

[James k]

Hi,
Thanks for the replies. I did change the head gasket a few months ago so the exhaust has been disturbed. I'll check the joints. The ignition and fuel systems have been checked over recently and are all in order.

Thanks,
James