Heavy Traffic Clutch Woes - slipping.....

[hugepiece]

I've now had an issue on two trips where I have been stuck in heavy traffic (more than an hour or so of stop-start stop-start) - the cluth starts to feel like it slips and bite point moves right up the pedal. You can smell the clutch burning slightly to as it struggles to pull away. I'm assuming it's the fluid boiling over or something as after the car has cooled down it's all fine again??? This has only happened twice in 6 months and only in real heavy traffic. I had a new trevor clevor kit fitted less than 3,000 miles ago and is perfect apart from this........Should I be changing my fluid? or is this a case of TADTS?

[SI-PEN]

Yep, fluid change would certainly help you, I'm just about to change to DOT 5.1 as it has a higher boiling point just in case I get the same problem.

[longbow]

Had this in my MR2 - basically over time the clutch (and brake) fluid absorb water via the vent hole in the master cylinders, to a point where it is actually the water that 'boils' into vapour causing the above effects. Chances are changing the fluid will fix this..................

[AlVal]

SI-PEN said:

Yep, fluid change would certainly help you, I'm just about to change to DOT 5.1 as it has a higher boiling point just in case I get the same problem.

I hope you took more factors into account than that with the change to 5.1, 5.1 doesnt have the propensity to absorb water, which is a good thing if you have an installation which is a very well sealed system with no chance of moisture getting in anywhere. If you can achieve this in a cerbera, id be very impressed, with the way seals etc. are. I far happier specifying a very good dot4 which will tolerate some level of moisture in the system which is bound to happen in no time in the cerb.

[SI-PEN]

AlVal said:

SI-PEN said:

Yep, fluid change would certainly help you, I'm just about to change to DOT 5.1 as it has a higher boiling point just in case I get the same problem.

I hope you took more factors into account than that with the change to 5.1, 5.1 doesnt have the propensity to absorb water, which is a good thing if you have an installation which is a very well sealed system with no chance of moisture getting in anywhere. If you can achieve this in a cerbera, id be very impressed, with the way seals etc. are. I far happier specifying a very good dot4 which will tolerate some level of moisture in the system which is bound to happen in no time in the cerb.

Wot!

[GreenV8S]

AlVal said:

I hope you took more factors into account than that with the change to 5.1, 5.1 doesnt have the propensity to absorb water, which is a good thing if you have an installation which is a very well sealed system with no chance of moisture getting in anywhere. If you can achieve this in a cerbera, id be very impressed, with the way seals etc. are. I far happier specifying a very good dot4 which will tolerate some level of moisture in the system which is bound to happen in no time in the cerb.

I suspect you're confusing DOT5 and DOT5.1. DOT5.1 is the correct stuff to use and does not suffer from the problems you mention.

[hugepiece]

thanks all, thats put my mind at rest! will get fluid changed asap

[copilot]

hugepiece said:

I've now had an issue on two trips where I have been stuck in heavy traffic (more than an hour or so of stop-start stop-start) - the cluth starts to feel like it slips and bite point moves right up the pedal. You can smell the clutch burning slightly to as it struggles to pull away. I'm assuming it's the fluid boiling over or something as after the car has cooled down it's all fine again??? This has only happened twice in 6 months and only in real heavy traffic. I had a new trevor clevor kit fitted less than 3,000 miles ago and is perfect apart from this........Should I be changing my fluid? or is this a case of TADTS?

My cerbie had this problem going to Le-Mans this year. It was dificult to tell exactly as I was not driving the car (currrntly in a pot) but I wasn't sure if it was the fluid or the seals.

While it quite probably could be the fluid, would worn seals give a similar feel/problem?

Copilot

[AlVal]

GreenV8S said:

AlVal said:

I hope you took more factors into account than that with the change to 5.1, 5.1 doesnt have the propensity to absorb water, which is a good thing if you have an installation which is a very well sealed system with no chance of moisture getting in anywhere. If you can achieve this in a cerbera, id be very impressed, with the way seals etc. are. I far happier specifying a very good dot4 which will tolerate some level of moisture in the system which is bound to happen in no time in the cerb.

I suspect you're confusing DOT5 and DOT5.1. DOT5.1 is the correct stuff to use and does not suffer from the problems you mention.

youre right, dot 5 is the silicone based one, doesnt absorb water but on the good hand doesnt strip paint, which is why show cars and the military use it - still, if we're comparing dot 4 and dot 5.1, its interesting that you compare the 198 degree celcius wet boiling point of the ate super blue dot 4 fluid and it blows away many dot 5.1s, dry boiling point only matters if youre fanatical and change fluid every race in a racing team, since the fluid becomes "wet" in no time at all! so you really have to compare wet points. 5.1 is designed more for abs systems which the cerb doesnt have too remember