Hi

Had the mini on the road for about 150 miles or so since rebuild, and the carbs have now developed a little backfire through them when backing off on the accelerator, and it also runs on sometimes (for about 2 seconds),

Any ideas?

Cheers

Matt

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68 Deluxe.... it's shiny..... I like shiny!!

Now it's worse, and overheating too! Any ideas?

I'm thinking it may be pre-ignition. What causes this?

Please help!

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68 Deluxe.... it's shiny..... I like shiny!!

my old motor did it as well, i did the easiest but stupidest thing ever, i mixed the spark plugs , that bazzled me for hour or so, but yeah relating to rotors its the mixture that can make em back fire through the carby,

but the thing that struck me was are you sure its not back fireing through an exhaust seal,

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any parts for a 76 clubby pm me or ring 0405 329 326

http://www.ausmini.com/forums/viewtopic.php?t=44717

Definately sounds like it's coming through the carbies, happens around 4K+ revs.

I run Optimax fuel, and thought the mixtures were pretty close.

I guess checking the mixtures again won't hurt. A few flats richer might sort the problem.

How do I check the radiator cap,? Seems to be a lot of coolant coming out.

Cheers
matt

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68 Deluxe.... it's shiny..... I like shiny!!

There is one easy way to find out whether it is backfiring out the carbies - pop the bonnet and take the air cleaner(s) off. Get someone to stand somewhere where they can see the carby intake, but WELL BACK (don't want a facefull of burning petrol). Rev the car and back off and get them to observe where the smoke comes from.

Well, we can only try....

Cheers

Anyone got More ideas on what causes this behaviour??

Matt

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68 Deluxe.... it's shiny..... I like shiny!!

ignition timing perhaps , have a look and see if your distributer clamp is loose , it might be moving itself around and advancing and retarding the timing at will .

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Check all the electrical connections on your coil and dizzy. I seem to remember reading a thread on here a few months back by someone with a similar problem that was caused by a loose electrical lead.

To check the radiator cap, you can try filling the radiator then leaving it idling and seeing if any water comes out as the engine builds up to temperature. Obviously if you don't have an overflow tank it will just go out the overflow pipe onto the floor anyway.