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Darn Carbs [I think] .....

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George Zeck

George Zeck

Jedi Warrior
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I proud to say my cost per mile is about $.10 per mile this season (& falling). Previous seasons were outrageous with the small projects as engine / tranny / etc .....

Have been running like a dream for ~ 6 weeks and as of the last few days -- problems. The "high idle" is back when I come to a stop. Seems to stop at 1700 - 2000 at a traffic light. "Goosing" the engine or backpulling the pedal doesn't help (anymore).

My overall problem - I believe - something wrong with the SU's. Possibly warped pieces or ?? / linkages are messed up / bent up ??

My thinking here is that when cruising -- all operates smoothly. Come to a traffic light and she doesn't slow down the idle too much (measured by the tach). Something is causing the 'SU parts' not to return to their normal low idle (1000 to 1100 sounds great and purrrrrrrs) without the force of a large spring (which apparently has 'broken in'). This leads me to believe that something is warped or bent vs. adjustment (new spring ?).

I am running a bit rich. Have "run on" most of the time when I turn the car off. Idle's high at a trafic stop.

Have rebuilt my carbs (myself and that could be the problem) ~ 5000 miles ago. Also, timing checks out. Do I have something warped / should I look elsewhere to solve the problems I am having ??

Reasonably handly on some things - just not SU's. Any idea's?

Tx-

George Zeck
/ubbthreads/images/graemlins/hammer.gif
 
George, it sounds suspiciously like a bad throttle cable. Disconnect it and see if things return to their proper place. While you have it unhooked at the carbs, undo the pedal end, and see if the cable moves freely in the housing. It should slide like butter. Better yet, pull the cable out of the jacket and inspect it for kinks or broken wires. All it takes is one broken strand of wire inside the housing for it to hang up. Lifting the pedal won't help, as then you are essentially trying to push the cable. Ever try to push a rope? /ubbthreads/images/graemlins/grin.gif
These cables are a known weak point, and I always carry a spare with me.
If the cable checks out OK, pull the air filters and make sure the throttle butterflies are returning to the fully closed position. If the connecting linkage has somehow slipped, it could cause the throttle to hang.
Been there quite a few times.
One other item to look at is to make sure the jets are free to move in the bushings. A jet that sticks will cause the car to run rich, and the idle will be high. That's what the return springs on the choke are supposed to do, make certain that the jets slide up to the proper position when the choke is off.
Jeff
 
Can you physically push the throttle linkage back to a normal idle from under the hood? If so, I think something's hanging - either the throttle cable, something in the linkage, or perhaps one of your butterfly disks is slightly off-center.

If you can't push it back, can you just adjust the idle lower? If not, try syncing the carbs. It could be that the butterfly on one carb has reached it's stop while the other is still too far open.

Good luck!
 
Hello George,

make sure both pistons are free and if lifted fall back down with a click, if one does not then check the jet centring.

Alec
 
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