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 Posted: Nov 22, 2020 08:55AM
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CA
Don't touch the carb(s) - that will take you farther away from the solution and only generate more problems. (The primary connection between the carb and the clutch is the driver!)

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"Hang on a minute lads....I've got a great idea."

 Posted: Nov 21, 2020 03:08PM
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Follow through with the tests Dan recommends.  carburetors, 1or2? Would not need be replaced, but I guess could be out of tune to the point of being something to adjust with a proper manual as a guide.

 Posted: Nov 21, 2020 12:22PM
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Thanks to onetim,Dan
if worst .replace carburetors can solve it?

 Posted: Nov 21, 2020 09:52AM
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CA
Quote:
Originally Posted by onetim
If this can be repeated with the car stopped, have a helper push the clutch, while you look for the problem. Possible cable routing/engine movement.
I thought about engine movement affecting throttle position, but the throttle cable (which he has replaced) is made to flex with engine movement not affecting the throttle. My next suspicion was some sort of drag when the clutch fully engaged (pedal released), but the opposite seems to be happening.

I agree to test the clutch with the engine running but in neutral to see if it clutch or throttle related. With the engine running in neutral and foot off the clutch pedal, observe the idle speed - should be somewhere around 800 to 1000 rpm. Then depress the pedal and see if the rpms go up or down. If the gear train is in good condition, the rpms might go down a small amount when the clutch is applying pressure to the crank thrust bearings. If the rpms do go up, there may be excessive drag in the drop gears and/or first motion shaft in the transmission.

Next test is with transmission in neutral, foot off the clutch and the engine idling. Rev the engine using the accelerator pedal. Lift your foot off the gas quickly. Does the engine drop to idle or does it take time to come down?

Next test is a road test. Drive the car at the speed and gear you have the problem at. Depress and hold the clutch pedal all the way down (coasting along). Don't shift gears - leave it in the gear you were running at. Take your foot completely off the accelerator. Do the rpms go up? Do they settle back to idle? How long does it take? Repeat this test in different gears.

Next test on the road is to shift gears up or down one (as when you get the problem). Do the rpms change when you select a different gear while keeping the clutch pedal depressed?

These last two tests might identify drag in the drop gear train or transmission.



.

"Hang on a minute lads....I've got a great idea."

 Posted: Nov 21, 2020 08:50AM
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If this can be repeated with the car stopped, have a helper push the clutch, while you look for the problem. Possible cable routing/engine movement.

 Posted: Nov 19, 2020 03:11PM
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87 cooper
when shift gear ,step on clutch ,RPM go up 
had replace throttle cable but can’t solve this problem
please
Thanks