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Carb help--idles too high

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drooartz

drooartz

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Moving along to the next problem...

Right before my breakdown and subsequent towing, I noticed that the Tunebug was not returning to the normal low idle when I was in neutral. It had run fine all day, but I pulled off the freeway and saw it was idling at about 2000 - 2200 RPM. It was still doing this on my test ride around tonight.

Where do I start looking? My knowledge of SUs is limited to pretty much knowing where they are on the engine. /ubbthreads/images/graemlins/grin.gif

Is this a dashpot oil problem? Adjustment screw somewhere? I've got the factory manual, Haynes, and Vizard books handy--is one of them the better source for details? This is my first foray into the world of SUs, so any help or pointers to other reasources would be apreciated.
 
Drew,

If the car will idle normally initially, but just doesn't return to normal idle after running at higher RPM, check your throttle cable/linkage. Sounds like you have a sticking/binding problem there. Lubricate everything well. Also, your throttle return springs might be stretched/worn.
 
Thanks for the link, Woodie. I'll take a look at that later today.

The car doesn't seem to want to idle at the normal level either. Prior to this the idle seemed normal (900 rpm? don't remember exactly, but it was low and smooth).
 
You could disconnect the cable and thereby rule it in/out as a source of the problem... kinda "quick 'n dirty" test, but it narrows the "suspect bits" somewhat. If it IS the cable, go to your local bicycle supply house and get TWO of the teflon liner'd brake cables, cut 'em to fit, slippery 'em up with a good cable lube and it'll astound ya... and cut both to length, stow the "extra" with your on-board spares kit. /ubbthreads/images/graemlins/wink.gif
 
hmm, Docs tricky tricks again but a good one for sure.
 
[ QUOTE ]
Thanks for the link, Woodie. I'll take a look at that later today.

The car doesn't seem to want to idle at the normal level either. Prior to this the idle seemed normal (900 rpm? don't remember exactly, but it was low and smooth).

[/ QUOTE ]

Normally, inability to set idle low enough is due to worn butterflies; however, since this was a rather sudden development in your case, I suspect that the problem is the cable/linkage.
 
sticky cable, timing off a bit, or worn throttle shafts....
just a few choices; ) ....retune them and check ur cable...
should help at least..............z
 
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