new carb - won't idle ever, help please

[kee]

Howdo, put my new(ish) carb on yesterday amd it starts fine everytime but it just won't idle. it sounds like the auto choke is working on/off all the time it dies when it goes off.

its quite lumpy when driving, again like the auto choke is making it rev and pushing it along, even under light throttle, under heavy throttle its fine and is better than on the old carb.

does anybody have any pictures to make sure i've put everything back properly.
its a 1300 x/flow with weber twin choke with auto choke. on eleccy ignition.

thanks in advance, and apologies for a curse word thread but I'm lost and cant afford to get it set up properly if i can sort it myself.

[PhoenixCapri]

Does sound like auto choke being curse word. Its more than likely old and buggered so only solution might be to convert to manual choke.

Also what was it jetted for originally? Cause it could also have huge idle jets or something which would also flood the thing.

[kee]

just sprayed some carb cleaner down and its not as lumpy, but still cutting out as though no fuel is getting to it. its fine under throttle.

the carb has only covered 5k so its not that, it was fully working and came off a standard 1300, same as mine. next step is try cleaning the jets out.

[joem83]

Idle jets could have some crud in them, had a simular problem with my old 205, stripped them out and blew them out with some compressed air, worked a treat.

Failing that I have a webber from a 1.6 orion you could try.

[kee]

cleaned all jets and its still the same, idle mixture has been suggested next. other than that I'm thinking about putting the idle jets from my old carb into this one

[eightsix]

Idle jet might be clean, but the idle cicuit could have some gunk build up causing a blockage - also worth checking the pilot hole as the fuel may not be getting through and drawn into the engine due to a blockage.

[DavidB]

Take it apart and clean it. I'm having troubles with my carb.

[kee]

bump, still not working
cleaned all the jets, sprayed all the gaskets to check for leaks, adjusted the mixture and still dying on idle, but comes back to life the second the pedal/cable is pressed/pulled

[morgs]

Right, this will pobably sound bunk but when I headed back down the garage this week, I reset the valve clearances, re attached the HT leads and went to start it. Well, after getting 3 and 4 leads the wrong way around...I was tired, alright?! Bruce and put it back together and nothing clever happened. So looking at everything again, we discovered that the dizzy housing was free as a bird and we'd shifted it with our fiddling. By spinning it back around a touch at a time until we'd spun it enough, we went from nothing but turning over, to spit back and then exhaust farting until we eventually went far enough and the carbs ran beautiful.

So, it's not a recommended process, but maybe slacken off the dizzy housing, get a mate to start it and advance/retard the timing by gently turning the dizzy until it no longer runs lumpy.

Failing that, try what others have said and I wish you all the best. It's worth perservering with though 'cos they sound like angels wailing on AC/DC when they're up and running properly ;D

morgs

[skinley]

Could be an air leak somewhere, are you sure all the gaskets between carb and engine are ok?

[turbokitten]

Sept 11, 2009 19:35:19 GMT kee said:

bump, still not working
cleaned all the jets, sprayed all the gaskets to check for leaks, adjusted the mixture and still dying on idle, but comes back to life the second the pedal/cable is pressed/pulled

I had exactly the same symptoms, was a duff carb base gasket between the carb and manifold. Spraying WD40 or whatever on the gaskets will only show up a decent size leak.