Hi guys,

I'm really stumped here so need help.

My sons Punto Evo, 1.4, 77bhp has developed a massive problem that I can't figure out.

The clutch works fine, goes into gear no problem and even drives forward and backwards under its own power.

The problem I have is that the moment you put the clutch down the car stops dead as though you have stepped on the brakes.

My son said it started grinding at the end of the road 200 yards away and developed the stopping dead thing when he was parking up. (May be just a typical teenage defence.)

I've never come across anything like this before so need help please.

Thanks guys.

shiny8163 said:

Hi guys,

I'm really stumped here so need help.

My sons Punto Evo, 1.4, 77bhp has developed a massive problem that I can't figure out.

The clutch works fine, goes into gear no problem and even drives forward and backwards under its own power.

The problem I have is that the moment you put the clutch down the car stops dead as though you have stepped on the brakes.

My son said it started grinding at the end of the road 200 yards away and developed the stopping dead thing when he was parking up. (May be just a typical teenage defence.)

I've never come across anything like this before so need help please.

Thanks guys.

Click to expand...

Hi. Thats an odd one.

It is basically a Grande Punto.

Look in the GP section.. may well have happened in 10 years of UK use.

(Not sure what the failed gearbox bearing scenario can feel like once BAD..)

Charlie

When you say stop dead, I assume you mean at low speeds, not driving at 20 mph and the wheels lock up. Shuffling into a parking space and it’s like putting the brakes on kinda stop dead?

AndyRKett said:

When you say stop dead, I assume you mean at low speeds, not driving at 20 mph and the wheels lock up. Shuffling into a parking space and it’s like putting the brakes on kinda stop dead?

Click to expand...

Yes.. like a partially seized bearing I assume they mean..

Enough drag to replicate brakes..
But not enough drag to overcome @30bhp..

Hi guys,

Thanks for the replies so far.

I do mean at slow speeds.

I have moved it forward in 1st gear but when I put the clutch down the car stopped moving as though the brakes were binding.

It was doing the same in reverse but now won't move forward at all.

I've had the n/s wheel off to check and the brakes are free.

I can turn the wheel backwards (clockwise) but when I try to turn the wheel towards the front it just jams up and won't turn.

It feels like the drive shaft is jamming up somewhere.

I may have to take it off and check it but if I can get some other ideas of what to try before I start stripping it out I'd be grateful.

As I've said I've never come up against anything like this before.

I have a day off tomorrow so am going to try to have a look at it in daylight.

Hopefully I may have missed something in the dark.

Good luck. Do let us know what you find.

varesecrazy said:

Good luck. Do let us know what you find.

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I will do.

Fingers crossed.

Had a look today in daylight and I'm still no further forward.

Jacked up both sides of the car and both wheels rotate in both directions with no noises or sticking anywhere.

I had my wife sit in the car and start her up so we could try it in gear.

It works fine in reverse but when we tried 1st, 2nd & 3rd gears the wheels refused to turn and the engine stalled.

Worried that it may now be gearbox related unless anyone has any idea of what else I could try.

Symptoms so far are;

Both wheels on the ground, the car won't move forward or reverse under engine power.

One side of the car jacked up, wheels will not turn at all by hand.

Both sides of the car jacked up, rotate one wheel by hand and the other turns in the opposite direction. (does the same on both sides)

Both sides of the car jacked up and using the gears, reverse is fine with both wheels turning but the wheels won't turn in a forward motion and the engine stalls.

Any ideas would be very welcome guys.

Thanks,
Shiny.

Sounds like the diff.

From my limited experience.

See the GUIDE in the cinq section from whitz

varesecrazy said:

Sounds like the diff.

From my limited experience.

See the GUIDE in the cinq section from whitz

Click to expand...

I'll have a look at that and let you know how I get on.

Thanks.

There are issues with a GP gearbox bearing..

But exactly what it effects I am unsure.

Plenty of info on the forum.
Melanabb had hers rebuilt by a specialist

shiny8163 said:

I'll have a look at that and let you know how I get on.

Thanks.

Click to expand...

Sounds like a broken pinion in the differential to me. Probably cheapest in the long run to just put a replacement gearboox from breaker in it. You could relace the diff and then find it's caused other damage.


Robert G8RPI.

g8rpi said:

Sounds like a broken pinion in the differential to me. Probably cheapest in the long run to just put a replacement gearboox from breaker in it. You could relace the diff and then find it's caused other damage.


Robert G8RPI.

Click to expand...

Just my luck.

Only bought the car about two months ago and already it's causing me grief.

This is the third Punto Grande we've had in the family and I've never had as much bother as I have with this one.

Will keep you updated with how I get on.

Thanks.

Hi shiny, very sorry to hear of your problems. From what you are describing it certainly sounds to be internal gearbox gremlins. It would be interesting to strip it and find out what's happened but at the end of the day your best option, as suggested by g8rpi, is probably going to be a good (with guarantee) used box. It seems likely there's been an internal failure of something. When this happens, because the whole box shares the same oil, it's common to find lots of horrid little shards of metal from whatever has failed, spread generously around all the other bearings, embedded in synchro rings, and blocking up oilways - I could go on.

It interests me however, to speculate on your observations so here's my ha'penny worth.

If you suspend the front end of most front wheel drive vehicles so the the wheels can be spun you will find that, with a stationary engine, a gear engaged and foot off the clutch you will get the effect you see - that is if you rotate one wheel clockwise the other will go anticlockwise. The reason for this is that with the engine stationary, clutch gripping and a gear engaged the gearbox is locked stationary. Therefore the pinion gear and crown wheel cannot turn. The bevel gears in the differential are perfectly free to turn though which produces the above result. Yours seems to do this? So it's likely, and I can only say likely, that the bevel gears are ok. But you say that you cannot turn a wheel if you jack up just one wheel with the other on the ground? If the gearbox is in neutral then turning just one wheel would cause the crown week to turn which would rotate the pinion gear and output shaft with its gears inside the box. You say it's solid when you try this. That's about the only positive thing I can say as I can imagine a few things such as - broken pinion as g8rpi suggests being just one. Anything which might stop the crown wheel from rotating from broken teeth (crown wheel/pinion) bits of gear tooth or broken bearing jammed in a gear? No! Stop! I think this is a bit pointless as the only way to really know is to strip the box and it's only worth doing that if you intend to rebuild and if you're going to rebuild you really need to recon the whole box as there may well be damage to other bearings etc which will only become apparent after you've reassembled it and got a few miles on it.

So sorry to sound so gloomy. Do keep us updated. It would be lovely to hear it was something cheap and simple - I'll keep my fingers crossed for you!
Regards
Jock

Can't get any more gloomy Jock so thanks for your input.

Any input is helpful and giving me more ideas of what to look at.

I'm not very confident at stripping down a gearbox and would probably rebuild wrong and end up with 1 forward gear and 5 reverse gears.

Reluctant to strip it down but I may change my mind if everything points at the gearbox for definite.

I like a challenge but at this time of year and with no garage it's not a great thought.

It may be a case of recovering it to a specialist.

I'll let you know if it gets that bad, and if it does, what they find inside.

I'm not giving in just yet.

Pugglt Auld Jock said:

Hi shiny, very sorry to hear of your problems. From what you are describing it certainly sounds to be internal gearbox gremlins. It would be interesting to strip it and find out what's happened but at the end of the day your best option, as suggested by g8rpi, is probably going to be a good (with guarantee) used box. It seems likely there's been an internal failure of something. When this happens, because the whole box shares the same oil, it's common to find lots of horrid little shards of metal from whatever has failed, spread generously around all the other bearings, embedded in synchro rings, and blocking up oilways - I could go on.

It interests me however, to speculate on your observations so here's my ha'penny worth.

If you suspend the front end of most front wheel drive vehicles so the the wheels can be spun you will find that, with a stationary engine, a gear engaged and foot off the clutch you will get the effect you see - that is if you rotate one wheel clockwise the other will go anticlockwise. The reason for this is that with the engine stationary, clutch gripping and a gear engaged the gearbox is locked stationary. Therefore the pinion gear and crown wheel cannot turn. The bevel gears in the differential are perfectly free to turn though which produces the above result. Yours seems to do this? So it's likely, and I can only say likely, that the bevel gears are ok. But you say that you cannot turn a wheel if you jack up just one wheel with the other on the ground? If the gearbox is in neutral then turning just one wheel would cause the crown week to turn which would rotate the pinion gear and output shaft with its gears inside the box. You say it's solid when you try this. That's about the only positive thing I can say as I can imagine a few things such as - broken pinion as g8rpi suggests being just one. Anything which might stop the crown wheel from rotating from broken teeth (crown wheel/pinion) bits of gear tooth or broken bearing jammed in a gear? No! Stop! I think this is a bit pointless as the only way to really know is to strip the box and it's only worth doing that if you intend to rebuild and if you're going to rebuild you really need to recon the whole box as there may well be damage to other bearings etc which will only become apparent after you've reassembled it and got a few miles on it.

So sorry to sound so gloomy. Do keep us updated. It would be lovely to hear it was something cheap and simple - I'll keep my fingers crossed for you!
Regards
Jock

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Jock,

Just reading what you said again, when I jacked up the car and the turned one of the wheels the car was in neutral not in gear when they were turning in opposite directions.
Does this make any difference?

PAJ,
My take from the description of the fault and testing is that the differntial is operating in reverse only and loking up when driven forward hence cant turn one wheel forfard with the other on the ground. One end of a pinion journal sheared or bearing failed could cause this. My suggestion to replace box is same logic as yours, it only needs one bit of metal lurking to wreck all the work rebuilding it.
Rebuilding a modern gearbox is not for the faint hearted. You CAN easily get 5 reverse gears just by putting the diff in back to front.
Looks like even a recon 'box is under £400 and a used one £100-200 so not that expensive.

Robert G8RPI.

shiny8163 said:

Jock,

Just reading what you said again, when I jacked up the car and the turned one of the wheels the car was in neutral not in gear when they were turning in opposite directions.
Does this make any difference?

Click to expand...

Hi again. The bevel gears' there are 4 of them, run inside a cage which is bolted (or otherwise fixed) to the differential crown wheel. Two, one on either side, of the bevel gears are mounted on the driveshafts which go to the wheels. The other two bevel gears are mounted, free running, on a pinion shaft which is fixed to the diff cage. There are some very good You Tube videos which describe how it all operates. If both wheels are off the ground then turning one wheel will turn the bevel gear connected to it which will cause both the free running bevel gears in the diff cage to rotate thus driving the bevel gear connected on the other side of the diff cage and causing it to rotate in the opposite direction to the one you're turning and so you will see the other wheel turning in the opposite direction. Whether the box is in gear or not probably won't make a great difference to what you see because the internal drag of the box will mean that the crown wheel will not move much even if the box is in neutral. If the gearbox internals move a bit while you're doing this you might notice that the wheel on the other side to where you are is not turning as fast as the one you are moving. The reason for this is that the crown wheel may be slowly turning allowing the diff cage, with it's internal bevel gears, to tumble a little.

Now consider what is happening if you leave one wheel on the ground. Now the bevel gear inside the diff cage which is directly connected to that wheel's drive shaft is not going to be able to turn. So if you now try to turn the wheel that's off the ground the bevel gear connected to it's drive shaft is going to have a turning force applied to it which will try to turn the two free running bevel gears which are on the pinion shaft in the diff cage. But the bevel gear connected to the other wheel can't turn because that wheel is on the ground. If the gearbox is in good condition and in neutral (no gear selected) then the bevel gears will "climb" around the stationary bevel gear and drive the diff cage which is connected to the crown wheel which is in mesh with the pinion gear which is splined to the output end of the gearbox 3rd motion shaft (output shaft) which carries the driven gears. If no gears are selected then all of this should be free to rotate so you will find you can easily rotate the wheel that is suspended. If anything is stopping this rotation - for instance you could select a gear. Now, because the engine is not turning and the clutch is engaged (foot off the clutch pedal) If you select any gear you will not be able to turn the wheel any more. likewise if anything on the output side of the box is damaged/jammed. For instance, but not an exhaustive list, Damaged bearings. Damaged, chipped or missing gear teeth. (it only takes one small chip!) Foreign bodies in the gear train (a broken bit of something from somewhere else in the box) the possibilities are multitude but if any of it stops the output side of the box from being able to rotate then you won't be able to turn that wheel.

You might find that if you violently rock the wheel back and forward - careful, don't knock the car off the stand (you're not doing this on a jack alone are you?) - if the obstruction is not too well wedged in, you might be able to temporarily free it. However it will do you no good because driving it will just do more damage and it's very likely it will soon jam up again. It might give a little satisfaction though! Don't be surprised if you can't free it though as the forces at work are very great.

Just to illustrate. Back in the 1970's I ran a Triumph Vitesse. (Sporty six cylinder engine with rear wheel drive) One day, on my way home about a mile from home, as I pulled away quite quickly from the lights there was a loud bang. It seemed to come from the back of the car. I immediately pulled over and had a quick look but could see nothing amiss. Within about a hundred yards the car seemed to loose power even though the engine sounded to be pulling normally. I decided to stop and have another look but had to find a place out of the traffic to stop. Suddenly another but different loud bang. the "drag" disappeared and she drove normally again so I drove the last half mile home. After tea I went out with my torch to find a nice wee puddle of gear oil on the road under the back of the car. What had happened? Well the first bang was a large chunk of crown wheel tooth breaking off. I assume it was picked up from the bottom of the diff case by the circulating oil flow and stuffed itself up the back of the crown wheel between it and the back of the casing where it acted like putting your foot on the back wheel of your scooter, that's why she slowed up. Until the forces became so great that it burst out the back of the casing and freed the crown wheel up to rotate freely again. Of course the crown wheel very happily flung most of the oil out the hole! The whole thing was an absolute disaster. I had to get another complete diff from a scrappie and one of the fixing bolts led me a merry dance for a couple of evenings before it would give in and let me remove it!

So, on that thoroughly depressing and gloomy note I'll wish you good night. Don't forget to let us know how it all turns out though won't you because it all adds to our knowledge base even if it's not "happy news"'
all the best
Jock

Guys,

Thanks for all the advice so far but after spending more time underneath it today I've decided to ask for help locally from someone with more experience than myself as I'm getting too old to be lying out in this cold.

I've sourced a reconditioned gearbox with a years guarantee in sunny Oldham for about £400 so if this guy says it is definitely the gearbox then that's the way I'm going.

I will update the post once I've had it looked at and I know better what's wrong with it and if it is the gearbox I will strip down the old one and try to post pictures.

Will probably need help with that too.

Will be in touch soon but it's coffee time now to heat me up.

Thanks again guys.

I think we all know about the age thing..