Author Topic: Carb setup (Read 4007 times)

Milky · « **on:** September 26, 2005, 07:44:25 PM »

I finally got to drive my BIS for a few miles yesterday, to take it to my nephew for some Exploratory Polishing. (Amazing what G3 and a buffer will do)

It starts ok with full choke and full throttle, and then ticks over not too bad. The choke doesn't seem to raise the revs any though, not as much as I would have expected anyway.

But, it does feel a bit lumpy, and backfires when I turn the ignition off.

I know these are not the quickest of cars, but it seems to have a flat spot in the rev range.

It also vibrates like hell at what I am guessing is around 3000 revs. I know this is not the exhaust baffles, as I checked these when the exhaust was taken off to replace the rocker cover.

Any ideas anyone?

Would it be an idea to take the carb off and give it a clean?

As usual, all help would be greatly appreciated.

fiatfsm · « **Reply #1 on:** September 26, 2005, 08:31:22 PM »

check your points condition and gap. not sure on the Bis but aircooleds are very suscpetible to wrongly gapped points and those symptoms sound like points trouble. maybe something else but worth a look IMHO.

Chris Lakin · « **Reply #2 on:** September 26, 2005, 09:20:05 PM »

Hi there Milky! Give the carb a good clean, get some carb cleaner from halfords. best thing you can do it clean the jets, mine were all chalked up and made it run rough. Use a think peice of metal i.e. of a small wire brush and poke it through. The flat sport is what i had and its the pump diaphram easily replaced its a sware shape with 4 screws hold top.

With the carb cleaner run teh engine for a little while then squirt it down, but do this after you have cleaned the carb out.

Do what Barry said too, i think the timing is crucial on the BIS aswell.

regards

Chris

Milky · « **Reply #3 on:** September 27, 2005, 09:25:25 PM »

Thanks for help again guys.

Looks like another Sunday locked away in the garage.

I will let you know how I get on.

Would anyone be interested in any pictures?

Milky

Chris Lakin · « **Reply #4 on:** September 27, 2005, 10:22:25 PM »

HI Milky!!! Pictures are always great!! we cant get enough of them, they will help people who have the same prob as yourself! So yes would be great to have some snaps!! Do you know if your carb is a weber or polish??

regards

Chris

Milky · « **Reply #5 on:** September 29, 2005, 09:23:50 PM »

Thanks Guys

Got some Carb Cleaner from Halfords, ran the engine for a bit, gave it a good old squirt.

Nice plume of black smoke, and then all seemed to be well.

Still got the flat spot, but it's ticking over much better.

Sunday will see the points and that checked, and also the Diaphram Chris mentioned.