punto reverse selection noise

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Thu 30 Sep 2004 10:43
punto reverse selection noise - sails north
hi, im wondering if anyone can help me diagnos a grinding noise on a 1.2 fiat punto 1999(mark 1) manual. the problem only occurs when attempting to engage reverse, it only occurs on the travel into reverse and once in gear it seems fine. all other aspects of the clutch/gearbox feel fine. to select reverse on this model you have to press down the selecter knob. any ideas??
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Thu 30 Sep 2004 13:44
punto reverse selection noise - Number_Cruncher
Hi Jambo,

It may be worth your while checking the clutch adjustment - make sure that the clutch is releasing properly.

number_cruncher
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Thu 30 Sep 2004 14:21
punto reverse selection noise - Peter D
Reverse is a straight cut gear and the only way I can think you get a grinding noise is if the input shaft is moving i.e. the clutch is dragging very slightly or not completely disengaged. Had this on a pug and on a Polo due to the auto adjuster on the cable not kicking in. The reason it doesn’t do it in first is because is has synchro so is stops the input shaft. Press you foot half way down on the clutch, engine off, and let your foot slip sideways off the pedal so the pedal shoots up rapidly, this should allow the clutch adjuster to take up the slack and allow the clutch to disengage properly. On hydraulic clutches either the adjustments needs checking or you air in the system. Regards Peter
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Thu 30 Sep 2004 20:05
punto reverse selection noise - Dynamic Dave
As Peter says, the reverse gear is straight cut, so the teeth don't always align first time - hence the grinding noise.

auto.howstuffworks.com/gear2.htm

The forward gears are helically cut.

auto.howstuffworks.com/gear3.htm

It might help if you select one of the forward gears before selecting reverse. Another tip is to wait a few seconds after pressing the clutch before selecting reverse. That'll give the cogs in the gearbox a chance to completely stop turning before trying for reverse.
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