Help with carbs idle

[doridori]

So I was driving along fine and I came to a set of lights and suddenly my idle began climbing right up to 4200RPM. Which isn't good....

I'm fairly new to carbs, and I'm not 100% sure where to adjust the idle from. Some pictures up here, I've circled where I think the idle adjust is... Is this right?


Or how do I fix this problem?


Cheers.
Nick

[parrot]

The first photo with the two arrows pointing at screws are the correct location, one on each carb.

You adjust these in and out whilst listening with a peice of garden hose, or something of similiar bore. One end at your ear, the other close (but not actually in) to the bellmouth. Keep doing this till you get an even sound across all four throats.

If your idle was previously OK, it would suggest something has fallen off, or moved. Check your linkage thoroughly plus other things like your distributor timing. Perhaps the timing has shifted? The idle screws won't move on their own so probably something esle like a return spring falling off etc.

[doridori]

Wow, ok thanks.

Are you recommending me taking it to my mechanic, just cos I'm fairly new to the carb game...??

[doridori]

Sorry, also , where's the bellmouth...?

[parrot]

That's where the air enters the carb.

Look here (http://www.racetep.com/webtechpage.html) too.

Scroll down to the tech page links.

Have a good look around first. Check if your distributor moves (it shouldn't), check a return spring hasn't just fallen off. If this happens the throttles may remain partly open. Look for a missing vacuum tube etc. It is likely to be something obvious judging by your description.

[doridori]

Thank you so much!

[gumbie]

Sounds like a vacuum hose has come loose or broken check those