3.5 carb issues

Hi All,

just want to pick your brains on this one, have a 3.5 carb v8 in my series 3 thats just gone back on the road after 4 years, all is running ok but every so often when plodding along at 30 or 40 she starts running rough and somtimes even shoots a little flame out of the exhaust, you can feel it coming and when you do if i dip the clutch and give it a rev it all clears again and im fine for a few more miles..... i have changed the points and condenser but no change !

any thoughts at all ?

ta

Matt

Sticking advance ?

Dr_evil said:

Sticking advance ?

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hmm will check that tonight, it seems to be fine if i give it some welly its only if i'm plodding along :-(

Way anti lag turbo systems work is to reduce advance so ignition is on exhaust stroke or near enough giving huge rush of flame out of exhaust valve to drive turbo. Same idea could apply if the advance is sticking and then only moves when you give it a a bit of power to free it
Was just a thought

When you changed the points you didn't pull the rotor arm off without hold the base plate did you? Sometime this can dislodge the springs on the advance/retard - giving this problem. Took me ages to sort this was the problem on mine - I had to order new springs as they were slightly bent. Try making sure the rotor arm springs back against the spring when you rotate it.

just been having a look as it seems to be getting worse :-( everything looks fine in the dizzy springs look ok and everything moves fine.

i have just been given a set of new SU's from a mate that has gone down the injection route, and along with them a electronic dizzy. so i think at the weekend i might have a play fitting that lot and she how i get on !

I has a spare injection manifold if you fancy following him

Dr_evil said:

I has a spare injection manifold if you fancy following him

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hahah not sure im after injecting it, i quite like the roar of the carbs !

so in a little update i think you might be onto something with the advance, i have disconnected the vacume pipe and she runs fine apart from bogging a little when you put your foot down !?!

thoughts pls lol !!