I have the clutch lockup in forward and reverse. I have taken down the bell housing and found a broken cylinder in the clutch plate axis. See the photo for reference. It seems that this the cylinder part of the release bearing. I have replaced the clutch plate, cover and release bearing. After putting everything back. I still have issue. Forward seems to be alright however reverse gear will cause lockup. The only way to get out of it is to turn off the engine and put the gear in neutral. I have had my gear shaft bearing replaced 2 years ago. Does anyone know how reverse lockup occurs and how to fix.
Technical Manual reverse gear lockup
- Thread starter dtwkwok
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Technical Manual reverse gear lockup
I have my old release bearing here. That cylinder is cut diagonally the same as your one. It is the inner most part of the release bearing.
What do you mean by 'reverse gear lock up'??
Reverse has no synchromesh so it relies on the gears rotating with your hand pressure as you change gear and you can only do it when the car is stopped moving
Reverse gear is difficult to get if the reverse gears are worn but if you can only get reverse with the engine off then maybe your clutch is not fully releasing?
I have one damaged cog on my reverse where it is difficult to get reverse. I have to allow the gears to turn slightly with the engine before it will go in.
Have you bled the clutch ?
Another thought. Your damaged part looks scored. The release bearing has to slide up and down on a part in the bell housing so the clutch can release. Was that checked?
What do you mean by 'reverse gear lock up'??
Reverse has no synchromesh so it relies on the gears rotating with your hand pressure as you change gear and you can only do it when the car is stopped moving
Reverse gear is difficult to get if the reverse gears are worn but if you can only get reverse with the engine off then maybe your clutch is not fully releasing?
I have one damaged cog on my reverse where it is difficult to get reverse. I have to allow the gears to turn slightly with the engine before it will go in.
Have you bled the clutch ?
Another thought. Your damaged part looks scored. The release bearing has to slide up and down on a part in the bell housing so the clutch can release. Was that checked?
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When I engage reverse gear, it is connected up with the engine. Then I cannot release the gear back to neutral even pressing hard on the clutch. In order to get out of the situation, I have to turn off the engine and release the gear lever back to neutral position. I have never seen a guide tube per your attached photo before. I am not sure whether I have one in there. Usually, the release is slide up and down along the drive shaft by the lever action of the bearing fork.
On my car the guide tube being fitted makes sense because:
1. The input bearing inside diameter is 20mm.
2. The inside diameter of the release bearing is about 24mm
3. The release bearing only has wear marks that travel up and down the direction of the input shaft. There are no signs the release bearing was rotating on something.
Meanwhile, I did a test on getting out of reverse with the engine running and the clutch still not fully released. Reverse can only be released once the pressure is off the gears.
Have you tried jacking up the front of the car to see if the wheels are rotating when you are in gear with the clutch pressed?
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Just drive the car again. The lockup is momentary. I am wondering whether there is anything inside the gear box that could have caused it. Will it be some other bearings that are worn out. When I poured gear box oil out before taking out the bell housing, I noticed that the oil was thick and dark. Considering that I change the drive shaft bearing 2 years ago, the oil should not be in such a state in 2 short years.
My oil was very dirty after supposedly being changed by a garage before I bought the car. One explanation is with the drain plug removed there is still about 500ml of oil still in the box behind various walls. And that comes pouring out once you start rotating the box out of the car.
There is also a seal on the thick selector mechanism with the weight which can cause dirt to keep entering the oil. I changed that seal to try and keep the oil clean. Plus there is an o-ring on the top selector mechanism and my selector was leaking oil there a bit. The o-ring does not work very well if the selector mechanism wobbles. I put a plastic shim under the arm to tighten it up and then put locktight on the retaining bolt/nut thing. Top selector is now oil free. Thick selector is OK.
Finally there is that breather thing at the top of the selector cover, which is just held down by gravity.
But in the final analysis although my input bearing was completely shot and there was quite a bit of metal in the box my differential bearings still looked like new after 240,000 km. Other bearings were worn though and the shafts were noticeable less wobbly when I was putting it back together.
I replaced all of my bearings. I think it made a slight difference to the sound of the car. You can buy all of the bearings and the seals as a kit on ebay from one stop bearing shop uk
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Now that I have investigated my lockup issue further. I now have a new guess. The lockup seems to happen when I depress the clutch and put it into gear without releasing the clutch. I can tell that the resistance occurs gradually and eventually lockup with the shift. Do I need to put grease on the shift and the inner surface of bearing to allow the releasing bearing running smoothly?
Following on my earlier theory, can anyone tell how the release bearing works. Should the inner race move fairly easily? I suspect the bearing is not working properly the inner race does not move with the drive shaft and causing lockup. How do I check whether the bearing is working?
The inner part of the release bearing and the outer part of the release bearing are all solidly fixed to the parts of the release bearing that slot into the mechanism in the bell housing. *Only* the front part of the release bearing touching the pressure plate can move freely.
It is quite clear on my car the inner part of the bearing was never touching the rotating input shaft. All the wear on the inner part of the release bearing is only up and down the direction of the drive shaft - suggesting a guide tube that is fixed in place.
Try this simple check.
There is an inspection hole for the clutch lining near the top part of the bell housing behind a rubber cover. The clutch lining is solidly connected to the input shaft. To select reverse gear the lining should not be rotating and so the input shaft will not be rotating
If you are in neutral and the lining is rotating then the clutch pressure plate must be pressing on the clutch lining and then onto the flywheel of the engine.
I found a reliable punto gearbox photo from finland and I have checked the palio gearbox manual which is more or less the same gearbox as the punto.
The guide tube for the release bearing is part of the casting of the bellhousing.
https://www.fiatforum.com/downloads.php?do=download&downloadid=549
The guide tube for the release bearing is part of the casting of the bellhousing.
https://www.fiatforum.com/downloads.php?do=download&downloadid=549
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I think I have another theory of what happens with the clutch lockup. It could be the slave cylinder leaking or losing hydraulic pressure. If the clutch paddle is stepped on for a few second, there could be a loss of hydraulic pressure. As a result, the clutch is engaged with the flywheel even the clutch paddle remains pressed on. The clutch is locked up whether it is forward or reverse. It only happens in the first gear or reverse as this is the only occassion when using the clutch paddle to micro control the engine power to the wheels.
