[Supra Bob]

Ok... What would happen if someone mixed synthetic and regular fluid in their Cutch Master Cylinder?

I loaned my car to my bro last week to run to the store real quick. I asked him to stop and get gas and check the oil. When he got back he said that he topped off the clutch fluid for me also. I didn't think anything about it because in the hatch I keep a bottle of synthetic brake fluid for the brakes and a bottle of non-synthetic for the clutch. Today now, My clutch is soft on 3/4 of the pedal, and even when fully depressed I can still blip the throttle and make the car roll... shifting is a pain in the ass, its almost like I am shifting without a clutch at all and getting a gear when I am stopped is an exercise in strength. So I figured that maybe I have a leaky clutch line or something, and popped the hatch to get the clutch fluid out. I opened the bottle to find that it had never been unsealed, but the bottle of synthetic WAS unsealed...

I am guessing that I can just flush the line and I should be ok... Anyone put some input on this?

 

[supra_toy]

arnt' the brake fluid and clutch fluid differnt type/viscosity oils?

I would try starting with a flush first and go from there


do no harm
will

 

[Flyin' Hawaiian]

just flush it Bob! That's an easy one to do, open the line at the bottom and let everything run out of the cup. wipe down the cup to get it all nice and clean, then new fluid and bleed like a brake system.
What? You need the bleeder again??? :shock:
heh heh...
Chris

 

[Supra Bob]

Well, to my knowledge, they're pretty much the same thing. In the past I've used Brake fluid in clutches and never had a problem...

And as for the bleeder Chris.. No thanks man... I'd have it done well before it even got here.

I've never bled a clutch on a Mk II... where is the bleeder valve located precisely...or is it placed so that when I get under there, I won't be able to miss it if I tried to?

 

[Flyin' Hawaiian]

Here ya go Bob! It's right there on the pass. side of the tranny!

http://www.cygnusx1.net/supra/library/TSRM_MKII/cl/CL_005.html

It's not too hard if you just drive the right side only up on them cheapy plastic ramps! Just enough room to get in there and bleed in comfort...
Chris

 

[Supra Bob]

Real close, but no cigar.. Drivers side buddy :wink: But you were right, Its easy to see... of course... this whole job led me to yet another question.... but thats for another thread.. :wink:

 

[williamb82]

the clutch uses brake fluid. i think when the car was intially produced the highest you could get was dot 3, but dot 4 is fine. same stuff that goes in the brakes. also, the power steering requires dexron 2. since they dont make that anymore, just use dexron 3 automatic transmission fluid. why people pay more for a bottle cause it say power steering fluid on it is beyond me but to each their own.
william

 

[CarFreek]

Just to muddy this up-Ive heard people say not to mix dot 3 and 5 on brake systems-Never once on clutches-But, dont Syn and Min have different Shear Props?-Id flush er also- Mike

 

[Flyin' Hawaiian]

You are correct! Never EVER mix dot3 or 4 with dot 5 fluid! 3 and 4 is based on Glycol, while dot 5 is silicone based. In fact, unless you race, don't use dot5 in the first place, you'll never (at least I would hope not!) get to it's minimum 500°F boiling point on the street, and you may end up with a leaking brake system, as silicone tends to swell rubber parts more than the glycol stuff.