11 replies to this topic

[klivins]

In my rebuild I used all the parts from my old 998, incl the clutch and flywheel assy. After it got rinsed in the oil (infamous red seal gone), it started to slip. Thats normal. Purely because there is a specialist round the corner who does clutch repair by rivetting new plates on, I did this and got new 190 mm clutch linings on.

The slipping continues, after the engine warms up, and above 3500 or so rpms only.

Can the clutch pressure plate be too weak for my 1275 with 266 cam and stage 3 head? It is vero clutch.

 

[klivins]

bumping it to first page.

why would the clutch slip?

[Captain Mainwaring]

Did you degrease everything after it was all contaminated? Carbon Tetrachloride can be used to good effect degreasing clutch components without disassembling the entire assembly - maybe worth a try, though do take care with using carbon tetrachloride - do it outside, wear a bit of protective clothing and do it with all the clutch components cold. Squirt it in and operate the clutch with the engine idling.

 

I suppose it;s worth asking what friction material you had the clutch lined with - if it;s too hard then it may slip under load.

[klivins]

have no idea, what material it was. Clutch lining material I suppose, lol. I did wash the whole assembly with petrol and brake cleaner. Shouldnt be oily now,

[klivins]

Still, been searching the web over and over again. Is it known for a Verto clutch to be su sensitive for non-original linings? The original was 180 mm disc, now we fitted 190 mm in the clutch, thought it will be even better.

The engine probably pumps out 70 - 80 bhp at most. Do I need some special or stronger pressure plate for such engine?

thanks

[KernowCooper]

Remember any clutch which is slipping for whatever reason (oil or worn ) whilst slipping this leads to excess heat build up and this can be transferred onto the pressure plate and weaken its clamping force hence the slip, its always a good idea when a clutch has been slipping to replace the centre pressure and bearing as a complete unit.

[Spud_133]

I doubt it's the friction material, as my 1293 chucking out 93bhp is running perfectly fine on my 998 clutch, and I'm not gentle with driving it either.

[Captain Mainwaring]

I doubt it's the friction material, as my 1293 chucking out 93bhp is running perfectly fine on my 998 clutch, and I'm not gentle with driving it either.

 

 

There are as many grades of friction material as there are "plastic" - if the guy used linings that were too hard, then they will slip if the clamping force is too low. 

You can't just go relining brakes or clutches without knowing the application.

[jaydee]

In my rebuild I used all the parts from my old 998, incl the clutch and flywheel assy. After it got rinsed in the oil (infamous red seal gone), it started to slip. Thats normal. Purely because there is a specialist round the corner who does clutch repair by rivetting new plates on, I did this and got new 190 mm clutch linings on.

The slipping continues, after the engine warms up, and above 3500 or so rpms only.

Can the clutch pressure plate be too weak for my 1275 with 266 cam and stage 3 head? It is vero clutch.

 

 

You cant fit a 190mm clutch on a flywheel that was used with 180mm plates like any original verto assembly used on 998 engines, it will slip everytime. You need either to re-surface the fly or get a nes one.

[klivins]

Thanks jaydee.

Was thinking along these lines. The wear on the flywheel was so tiny - barely felt with fingernail. Thought the light surface rust on the fly would just imediately wear out.

If I were closer to the mini spare parts I would not try these measures, but once the clutch was out the options were - 10 days delivery of new clutch plate, or 2 hours of relining. Lets see how it goes. I have ordered new set anyway, in case this becomes unbearable.

[klivins]

clutch on the table again. Fitting new clutch assembly what finally arrived. The old-new clutch plate I got resleeved has been slipping on one side only - and not on the suspect flywheel side with slight marks from 180 mm disc, but the pressure plate side. Im puzzled by this, never did I think it was possible for clutch to slip on one side only!

[Captain Mainwaring]

clutch on the table again. Fitting new clutch assembly what finally arrived. The old-new clutch plate I got resleeved has been slipping on one side only - and not on the suspect flywheel side with slight marks from 180 mm disc, but the pressure plate side. Im puzzled by this, never did I think it was possible for clutch to slip on one side only!

 

I believe that the comment about disk size is very relevant but I would also look at that friction material before you put it all back.