Clio 16v transmission help

[Ben H]

My car is on axle stands at the moment, while the wheels are away being refurbished. I decided today to start the engine and let it idle for a while as I havent driven the car in a few weeks.

When I did this, I noticed that the driveshaft started turning by itself - rotating the discs in mid air! I dont know if this is unusual or not, but it certainly wasnt in gear. Anyway, thats not the problem:

What I also noticed was that the driveshaft seemed to turn nicely for 9/10ths of its radius, but would scrape something for that 1/10th, so that it gradually got slower and stopped.

In the few weeks before my car was laid up, I also noticed a gradually louder kind of humming coming from the front of the car - in or out of gear - above 30mph.

My questions are:

1. Would the friction causing that 1/10th be caused by the driveshaft being dodgy?

2. Could it instead be a warped front disc? (There are not obvious signs of that)

3. Could either of these be causing my 30mph+ "humming" from the front of the car? (in or out of gear)

4. Any other ideas?

Cheers

 

[adiclio16v]

mine does the above 30mph humming gradually got worse then i started having box trouble

its really loud now and my g/box is knacked

the rotating on its own is perfectly normal though

adi

 

[maciek]

1. Would the friction causing that 1/10th be caused by the driveshaft being dodgy?

prob. the brake... should check it. doesnt have to be warped though... it can just be some rust or whatever... but check it

/////Could either of these be causing my 30mph+ "humming" from the front of the car? (in or out of gear)

humming? well i would first of all check the wheel bearing. -this can also cause problem no1

/////noticed that the driveshaft started turning by itself - rotating the discs in mid air! I dont know if this is unusual or not, but it certainly wasnt in gear

i must admit that ive never tried this sort of experiment maybe the friction with no wheels on is so small, that even out of gear the gears are turning one another...? no idea

 

[Ben H]

Cheers guys. I dont think its a wheel bearing as I had all of them replaced about 10k miles ago, when I also had the discs and pads done.

I guess it could be the gbox, but Ive had no trouble selecting gears and it was overhauled about 20k ago. The diff is new too.

What are the symptoms of a dodgy driveshaft?

 

[lofty]

Robbie said drive round in circles on full lock and if it knocks your drive shafts are on thier way out, he certainly knows what hes talking about, and drive shafts are easy to replace proived nothing has been damaged inside the box

 

[Nick Read]

Mine did the same last time I did the same sort of thing with the wheels off - the hubs rotate because there is nothing stopping them from turning, there must be a slight contact between the engine and hubs even if in neutral?

 

[Anders]

To be perfectly honest there doesnt seem to be anything much wrong. All wheels rotate when off the floor and out of gear, the inertia of the engine and transmission make them, if you want to stop them then just chock them, no big deal.

As for the drive shafts, theyre meant to transmit all the torque from the gearbox to the wheels and you would have to have a huge power hike to make those puppies deform. As for turning lock to lock to determin a fault, WHY?? They are a straight bit of tube so it wouldnt make any difference, they are connected to the CV joint and it would be this component you would be testing for faults.

Dont worry.

 

[Ben H]

OK, cheers people. Seem to have come to the conclusion between us that the rotating and sticking is normal. The car never mades clicks of full lock, so I doubt its the driveshafts.

But that still leaves the gearbox hum! Its still there when I coast with the car out of gear - does that narrow it down any more?