Engine Stutter without Throttle

Symptom:

If I allow the car to move by letting the clutch up slowly (no throttle) it is jerky. The car runs for a few seconds and moves forwards but each time it gets to the jerky point (which seems cyclical) it struggles more and more to get passed it until it eventually loses the fight and conks out.

Any idea what might be causing this?

Water247 said:

Symptom:

If I allow the car to move by letting the clutch up slowly (no throttle) it is jerky. The car runs for a few seconds and moves forwards but each time it gets to the jerky point (which seems cyclical) it struggles more and more to get passed it until it eventually loses the fight and conks out.

Any idea what might be causing this?

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YOU- very seldom will a motor idle in gear and move with a manual transmission, they will almost always stall. Its a built in safety feature

Fur Trapper said:

YOU- very seldom will a motor idle in gear and move with a manual transmission, they will almost always stall. Its a built in safety feature

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I have to say mate, after this very blunt response you had me really doubting myself so I went out in a couple of other cars - AND SMOOTHLY TRAVELLED IN FIRST AND SECOND GEARS WITH NO THROTTLE

If Series motors don't then that is one thing, but "very seldom will a motor idle in gear and move with a manual transmission, they will almost always stall" just seems to be an incorrect statement (in my experience in perhaps 10-15 cars).

One of the reasons I wanted to have my engine idle and move in 1st or 2nd was because I was taken on an off-road driving session many years back and remember the instructor always telling me to get my foot of the throttle and just letting the clutch up and pull the car out of a spot. Also, whilst I have barely any off-road experience I always thought that when traction was a problem that you should let the car pull away with little throttle (my interpretation of that was none if possible) so as not to send excessive power to the slipping wheels.

If I've misunderstood then please take the time to explain it all to me as I don't have anything close to what I would consider 'knowledge' in these areas.

Mine happily runs on tickover in first - really useful in slow traffic! Try lifting the tickover just a tad and then check the setting of the slow running jet on the carb. A thorough service wouldn't go amiss, either.

oxides said:

Mine happily runs on tickover in first - really useful in slow traffic! Try lifting the tickover just a tad and then check the setting of the slow running jet on the carb. A thorough service wouldn't go amiss, either.

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"lifting the tickover" You mean increasing the idle set screw(?) (that the throttle arm rests on)?

"slow running jet" - the 'other' screw?!

...I have a Weber ICH47 which I think is only adjustable in two ways - that is the screw that stops the throttle returning and another one in the body of the carb which I presume adjusts the mixture somehow (though I don't know how) :doh:

As they are at the moment is about the only way I could get the car to run without stalling. The instructions I found for tuning the carb suggest starting with the mixture screw 2 turns out ("the engine will then run slow like a tractor, but as long as it is still running...") but my engine does stall and so I can't tune it according to the book.