Technical Clutch expertists...

[Ralf S.]

Gerrard (1.9 JTD 115bhp) has come over a bit moody in the gearbox/clutch department and I'm wondering if anyone knows for sure what's going on (apart from it's probably going to be expensive).

I last changed the clutch and slave cylinder exactly 70,000 miles ago. At the time, the old clutch looked pretty much worn out but it was a joint Fiat / Borg&Beck branded item, so it may have been the original factory plate .. but in any case it was the slave that had failed, rather than the clutch itself.

Now, the beast is becoming a bit tricky to change gear but the symptoms are a bit unusual and I'm trying to understand what might be happening in there (apart from it's probably going to be expensive).

If I trundle down the motorway for half an hour or more, when I come up the slip road or thereabouts, the gears may become notchy and difficult to shift. If I change gear a few times it seems to clear itself up but won't fully be smooth again until the engine has been switched off for a while (not running) when the beast is fine or just very slightly notchy again.

Gears engage nicely with the engine off, so I'm sure it's not the linkages (but they're well greased anyway).

The clutch pedal always moves smoothly and returns properly and fluid is stable so I'm fairly sure that a slave leak is not causing problems (although bleeding the slave did make things better for a couple of weeks). Last time the slave failed it was dropped clutch pedal/losing fluid/obvious symptoms.

The gears work fine when it's fine so I don't know how it can be a gearbox problem (I'd expect it to be consistently notchy).

Clutch take-up is a bit more juddery when the beast is playing up but excellent when it's not... so again, I'm not convinced it's the clutch.

What's a wonky flywheel feel like? The beast has 195,000 miles on it now, so it may be knackered/contaminated.

Could the slave cylinder be working strangely/intermittently? It was the slave that failed last time, so it's my chief suspect this time. The clutch and slave in there at the moment are Valeo, so not ****e. 70k seems a bit early to die, if the old Fiat/Borg one managed 125,000 miles.

Any other ideas? I suppose ultimately I'll have to take it apart to find out what's going on but knowing in advance might be useful (e.g. I can buy a new flywheel/clutch/cylinder etc. before I dismantle it).


Ralf S.

 

[portland_bill]

It appears that the clutch is not clearing properly when hot. Clutches don't tend to distort with heat, unless extreme, and then the damage is permanent. My guess would be contamination with oil, probably from the gearbox input shaft seal.

Other options.
Input shaft splines rusty, or contaminated.
Often people put coppeer grease on the splines, a really bad idea, as it attracts dust, and has no ability to stay in place, so flings out onto the clutch lining. Even a tiny amount, often difficult to see, can cause judder, but this usually happens almost immediately after a new clucth is fitted. Ideally the splines should be lubricated with graphite, nice and slippy, not sticky, so does not attract dust. Just rub a very soft pencil on them.

The cover plate assembly has three spring steel plates that attach the pressure plate to the cover pressing. These can lose their tension if the cover is dropped, any time from manufacture to fitting. This can lead to dragging and judder as the pressure plate does not fully retract. Symptoms usually manifest soon after fitment, but if damage is slight can take some time for any heat build-up in use to weaken them further.

The gearbox is located on dowels, to ensure alignment. As the gearbox is alloy, and the dowels are steel, if not properly located, then pulled in with the bolts, the dowels can either push through so not doing anything, or cut into the alloy. Then engine and gearbox are not aligned, clutch centreplate works eccentrically. How far offset will affect its life, some fail very quickly, otherrs take a long time.

Everything needs the clutch removing to diagnose, so sadly there's no shortcut, gearbox has to come out. Once out, if fault not obvious, post very good pics of both sides of the centreplate, both sides of the cover assembly, and of the mating face of the bearing.

 

[Ralf S.]

It appears that the clutch is not clearing properly when hot. Clutches don't tend to distort with heat, unless extreme, and then the damage is permanent. My guess would be contamination with oil, probably from the gearbox input shaft seal.

Sorry for not replying before - I was working away from home for a few days with no internets.

Thanks for the comprehensive reply. The first option sounds most likely the cause.

When I changed the clutch there was a fair amount of grime inside the bell housing which looked like a combination of hydraulic fluid, clutch dust and other dirt.. but it did strike me as also a bit oily. I cleaned it all out and the input shaft seal did seem to be mostly okay.. but I wasn't completely confident that it was not leaking at all.

The old clutch was clean though and still had some life (the cylinder had failed, rather than the clutch itself), so in the end, since I had no spare seal and the car was off the road/on stands in the middle of the driveway, I left the original seal in there with a note to self that I might want to remember to change it next time.

At the moment it's behaving itself - some shorter journies in the last couple of weeks probably helps to burn any contamination off the clutch plate, so I'll probably leave it until/unless it gets worse. It'll probably become undriveable when the MOT is due and the temperatures have plummetted to minus 5C etc.

I'll bleed the clutch some more and check the gearbox oil too, since it can't hurt.. but when it's not doing "moody", it's all very good down there.



Ralf S.

 

[Ralf S.]

The clutch is still hanging gamely on..

Although as the fairer weather may (hopefully????) be on the way, it's working its way to the top of my "to fix" list (I think just air-con condensor and cam-belt are ahead of it, unless it packs up altogether).


My latest thought (other than the must-be-leaking output shaft seal.. there is habitually a trace of an oil leak under the clutch bell-housing) is that the flywheel could (or could also) be knackered.

It looks like the Stilo JTD 115 has dual mass flywheel. How long do these last, do we think? And what do they feel like when they're failing? When mine is being moody, it can judder, like a worn CV spider (n.b.. my driveshaft is fairly new).

Gerrard is an old beast now... and the flywheel is the one that it came out of the factory with, so no complaints aboot its longevity (even if it's putting the price of the repair up).


Ralf S.

 

[portland_bill]

It looks like the Stilo JTD 115 has dual mass flywheel. How long do these last, do we think? And what do they feel like when they're failing? When mine is being moody, it can judder, like a worn CV spider (n.b.. my driveshaft is fairly new).

They were designed to last the life of the car, but that seems to be the case only if driven sympathetically. Nice smooth starts and gearchanges. Harsh starts, and harsh gearchanges, put more stress on the springs in the flywheel, shortening their life. When these things were a new idea, I've seen some last weeks only. Driving style is paramount.

As they are designed to dampen engine vibrations, they will of course wear. Shame after all these years we are now designing engines which seem less smooth than older designs. Perhaps a result of better power and efficiency, something had to give. (The owner's wallet)

 

[Ralf S.]

The beast is a couple of days short of 205,000 miles, so the original DMF (if it's worn out and it's not just oil on the plate) would seem to have lasted "the life of the car" pretty well. They're available as aftermarket parts though, so a fair few must have packed up early, compared to mine.

There's rubber in there somewhere, as I understand... Does it tend to crumble or detach itself ... or how do they fail? Last time I looked (about 80,000 miles ago) it all looked clean and tidy in there but unless something obvious stands out, I dunno how I would tell whether it's knackered or not.

Is a seconda-mano DMF a good idea? Somehow I can't think it is.. but £250-plus Ahhhh Ahhhh for a replacement makes me want to believe...

Ralf S.

 

[Ralf S.]

And... output shaft oil seal. They look like a semi-circular plate with a hole in the middle of it.

Will it be easily accessible once I've removed the gearbox, clutch and flywheel...? Or do I need to also dismantle something else?

I presume I'll just unbolt the plate, slide it off the output shaft and then just fit a new one by sliding it on? Apart from there's the gearbox, clutch and flywheel to remove.. is it as simple as that, or is it a wrestling match?



Ralf S.

 

[chris3234]

The beast is a couple of days short of 205,000 miles, so the original DMF (if it's worn out and it's not just oil on the plate) would seem to have lasted "the life of the car" pretty well. They're available as aftermarket parts though, so a fair few must have packed up early, compared to mine.

There's rubber in there somewhere, as I understand... Does it tend to crumble or detach itself ... or how do they fail? Last time I looked (about 80,000 miles ago) it all looked clean and tidy in there but unless something obvious stands out, I dunno how I would tell whether it's knackered or not.

Is a seconda-mano DMF a good idea? Somehow I can't think it is.. but £250-plus Ahhhh Ahhhh for a replacement makes me want to believe...

Ralf S.

I believe the usual way to check for wear if to grab each half of the end and try to rotate them.in opposite directions and measure the ammout of movement the Max ammout depends on the manufacturer but often it's around 6-7mm max before it's considered worn

 

[Maxcaddy]

I would have thought...........how worn was your flywheel after 125,000 miles when you changed the clutch ?, as that will give you an indication how bad it might be now.

Output shaft (presumably you mean input shaft to the gearbox as the output shafts are the driveshafts ?), also known as the 'first motion shaft' oil seal, does wear out, and is usually a very straightforward repair (noting that some very straightforward Fiat repairs are a right dogs dinner). Although that would in dire case be more liable to give you clutch slip rather than gear engagement (assuming all the oil hasn't come out the box).

In trying to correlate your symptoms with prevailing conditions (which in English is when it goes wrong what's also happening at the same time) seems to say it's temperature/time related more than anything else, which (to me) says its a selector fault due to a hot gearbox, because the flywheel, and oil in the bell housing etc, is the same all the time so it would surely do it all the time.

Before taking the Box off (unless you're bored and like a challenge) I would categorically establish that the 'engagement and notchiness' had nothing to do with the linkage getting hot, or the cables sticking, or any other part of the operation extraneous to the Box itself .

 

[Ralf S.]

The flywheel looked a bit "second hand" last time .. but no visible signs of things decomposing, degrading, rotting, rusting or falling apart. I didn't test it (had to reason to suspect it of anything) specifically, other than blowing the dust off and seeing that it looked in reasonable condition.

My oil weep seems to be the input shaft seal... I knew what I meant.. It comes out of the bottom of the clutch bell-housing... but it doesn't drip onto the floor (or into the under-tray). It does leave the area around there a bit oily and collects a bit of grime but it's not too severe.

For a long time I thought the oil was escaping from the driveshaft but it didn't smell like gear oil.. and later on I fitted a new driveshaft with a new oil seal. I managed to tie a strip of old bedsheet round the driveshaft to see whether it got oily.. but it stays well and truly dry.

When I had the gearbox off, the inside of the bell-housing was a bit oily. I took it apart because the slave/release bearing was knackered, rather than the clutch itself.. but I fitted an all-new 3pc kit at the time. I didn't know if the "oily" was clutch fluid or engine oil.. but at the time it looked/smelt like a mixture or the two.

The symptoms I get are definitely "clutch" related. When the engine is cold, everything is fine. It can stay fine, if I drive it up the road (c10-15 miles) and may stay fine even if I drive 100 miles.

But anytime after 25-30 miles it can suddenly turn moody. I only notice it when I come off a motorway junction.. the gearbox becomes reluctant to change gear and the transmission rumbles for a bit, like a worn driveshaft might. If I pump the clutch pedal slowly, like I'm changing gear (even though I'm not changing gear) the gearbox comes back to normal.. but it remains a bit rumbly for 2 or 3 miles before fairly quickly going quiet and back to normal again.

The gear lever stiffness doesn't last very long.. just the first few times I try to change gear .. until the grumble/moodiness passes, so I'm fairly sure the linkages etc. are fine. I've bled the clutch and greased the liks at the gearbox end since the problem started. Only the bleeding seemed to help for a while.

I imagined it as some oil contamination getting onto the plate, to cause small slippages that give me judder. Then if I work the pedal a bit, it can burn off/clean up and then everything returns back to normal.

But if the DMF is turning a bit ginger, then that might be running out of true/misaligning itself? causing a vibration (the judder) and preventing the clutch from releasing properly a few times until everything gets straightened out by the clutch being worked.

I think I'll only be able to see what it is with the gearbox off.. Ahhhh but I'm fairly sure the gearbox is not the problem and that the linkages are okay. When it works it works smooooth... even in heavy traffic queues.... whereas the judder only happens when the car has been cruising in top gear for an hour or more....


Ralf S.

 

[Abarth L]

From what I can make of this long description is that the Flywheel were never changed.

When changing the clutch kit the Flywheel needs to be changed at the same time.
A FIAT dealer would decline to do just do the clutch kit.

The motor uses a DVA (twin damping flywheel) or commonly knows as dual mass flywheel.
The reason is to absorb the resonance pount at 800 and 2200 rpm and move it to a lower rpm outside usage range.

The reason why changing gears is now a challenge while at speed and driving, is because the flywheel don't absorb the resonance / vibrations as it should and it is being transferred to the gearbox.
That is why you can shift smoothly when motor is off.

 

[Pugglt Auld Jock]

What you're describing certainly sounds very much like dual mass flywheel problems. Does it ever "tinkle" or "clonk"? Some times you will feel a slight "pulsing" through the clutch pedal when held part way down.

If it's still the original fitment then you've done quite exceptionally well with it - could even be some sort of a record? There are special tools available which bolt to the moving part of the flywheel and allow movement between the two parts to be definitively measured. However sometimes after carefully measuring, and getting a "serviceable" outcome, they still fail after fitting just a new clutch kit! As mentioned above, many "professionals" won't fit just a clutch kit on it's own where a DM flywheel is involved as the gearbox has to be removed to later rectify the flywheel if it fails doubling the price of the job.

There are single mass conversion kits available for some engines - don't know about ours but it's big business with the VW stuff. However some people report them to be harsher to use and make the drivetrain harsher and noisier. Valeo in particular now make a kit with longer double springs in the driven (friction) plate which are claimed to cut down significantly on this harshness. I've never fitted one so can't recommend or condemn.

Your oil leak may well be the first motion shaft seal - a common problem on just about any manufacturers product, not just Fiat. However I know on our wee Pandas the seal is integral with the 1st motion shaft bearing so the 'box has to be partially stripped to remove the shaft and renew the bearing. Don't know if yours is the same, but if it's leaking don't ignore it as it will just eventually contaminate your new clutch friction plate and you'll be taking the 'box out again!

Good luck with it. Do keep us informed.
Jock

 

[Ralf S.]

Yes.. I think I've concluded that the problem is the DMF. The "oil on the plate" idea doesn't entirely convince me (even though it was my own idea.. ) since the vibration/juddering/stuck gear lever only happens when I come off the motorway... so any oil that may have contaminated the plate would have had to leak out while I'm driving along, get onto the plate without being flung off and then contaminate it as soon as I pressed the clutch in for the first time. I can't make the theory fit the symptoms any more..

The DMF was okay back at 125,000 miles... it made it to around 190k without any dramas so I'm not sure it was falling to bits and I didn't notice/I should have changed it... although it's a little bit boring that I didn't, since the clutch is probably in reasonable condition still (only 80,000 miles now, so about 60% worn based on my experience). The CSC is the more likely candidate to go wrong.

I've priced up a Valeo kit. They sell 2-pce kit (826354), a 3-pce kit (834005) and a 4-pce kit (837005) which includes the flywheel... as well as each component separately. There's a geezer in Italy selling the 4-pce kit for £358 which seems like a good price if/when he comes back on-line.

The imput shaft oil seal looks like a simple collar with bolt holes around it, and a neoprene seal in the centre. From its appearance off the car, it looks like it just unbolts and lifts away from the output shaft.. but I've never seen it, since it's behind the DMF. It's £30 for a Reinz.. half that much for an FAI (?).

That lot would double the value of the car.... but there you go...

Meanwhile.. I have the cam-belt and water pump to swap... it's just due now... and then I need to make sure the Younger Mrs S'. Rasputin will pass its upcoming MOT before I do anything major like swap my gearbox. I may need to borrow Rasputin while mine is off the road (clutch replacement isn't the work of a single afternoon.. )


Ralf S.

 

[Davren]

The imput shaft oil seal looks like a simple collar with bolt holes around it, and a neoprene seal in the centre. From its appearance off the car, it looks like it just unbolts and lifts away from the output shaft.. but I've never seen it, since it's behind the DMF. It's £30 for a Reinz.. half that much for an FAI (?).Ralf S.

The input shaft oil seal is in the gearbox bell housing.

The oil seal behind the flywheel is the rear crankshaft oil seal.
.

 

[Ralf S.]

The input shaft oil seal is in the gearbox bell housing.

The oil seal behind the flywheel is the rear crankshaft oil seal.
.

Thanks. Yes, the "rear crankshaft oil seal" is the one I meant.

It's difficult to find the proper names for things when a) you don't know what it's called in the first place and b) sellers put every conceivable name in their product descriptions so they appear in every search and c) ePer just calls it a "seal gasket"...

Your photos are dead useful. If the oil leak (which isn't tooooo shocking) under my bell-housing turns out to be coming from inside the bell-housing, rather than the left hand end of the sump, then I presume that the crankshaft oil seal is the only possible culprit. I'm inclined to buy the crankshaft seal and change it anyway since it's a long way to dismantle everything, just to leave the old one in there.

The input shaft seal I guess only holds back gear oil.. and the oil film that collects down there doesn't have the smell of gear oil. On the other hand, as above.. how easy is it to change that seal too? Is it a knock-in/metal-skinned doodah, like the driveshaft seals, or does the gearbox have to come apart like Jock says, to remove it from the other side?

Which seal is it, if I'm looking in ePer? My old beast is a JTD 115bhp "M50".


Ralf S.

 

[Davren]

Best to replace both oil seals whilst the gearbox is out.

Gearbox input shaft oil seal is part number 71719542.

To remove the old one, drill a small hole through it and screw a self tapping screw into the hole. Put grease on the end of the drill bit to catch any swarf. Make sure the drill bit doesn't go through to the bearing directly behind the oil seal, or the end of the bit could snap off. Then use a lever to pull on the screw head to get the seal out.

I made a drift to fit the new oil seal with some old plumbing pipe and fittings.
.

 

[Maxcaddy]

Okay I've broaden my horizons by reading about Dual Mass Flywheels on Wikipedia, and think I follow the logic which is to take out the drive-line shock load by making the flywheel act as a shock absorber. Not sure why this is essential, but presumably in a Diesel Stilo it is a noticeable benefit ?

However, I'm still struggling to understand that if it did go wrong (springs break, faces wear, seizes solid) that it would make changing gear more difficult and only at certain times ?. Okay, drive-line snatch and vibration could occur, but gear engagement ?. You've got me there

 

[Ralf S.]

Yes.. the sticky gearbox (for a few seconds it has to be forced into the lower gear.. then gradually, after a few changes, it gets back to normal) has me puzzled too.

I presume the DMF bearing is knacked and that's letting it run out of true, which might be interfering with the clutch plate and preventing it from releasing until the pedal has been pumped a few times to line everything up again... but I can't visualise it.

It often clatters at idle too, which disappears when the pedal is in, which is classic DMF. I won't know for sure what it's up to until I takes it apart.

If the weather clears up I might try to get hold of a 4-piece clutch kit and have a go fitting it while the Mylie-19 is keeping me at home/don't need the car for commuting. Unfortunately, the cheaper parts sellers seem to also be closed for the duration though...


Ralf S.