After boiling my clutch fluid at R9 I have decided to change it out.( and the brake fluid as well) A search has directed me to a replacement fluid however I did not see what quantity I should have on hand prior to the procedure. Anyone know?
Clutch/brake fluid change
- Thread starter Cobraguy
- Start date
PeteK
GT Owner
And change it regularly! It doesn't matter what brand you like, as long as you change it regularly. When I was racing Porsches at the local PCA events, Tech Inspection required it be changed at least every 6 months. ON a mostly street-driven car, I'd change it at least every two years. Curiously, neither the FGT owner's manual nor shop manual give a replacement interval for the brake and clutch fluid, therefore, you likely have the original fluid in your car. CHANGE IT NOW. Also Ford specifies DOT 3, which is the lowest boing point for glycol fluid. You can (and should, if you track the car) go up to DOT 4 or DOT 5.1, but NEVER DOT 5 (that's a silicone fluid).
Castrol is a good fluid and has a high boiling point. We like Motul RBF 600 and have had very good results with it.
Use a syringe and suck out every drop that you can from the small reservoir. Use a clean cloth after it is empty to wipe and clean the reservoir. Fill with the brake fluid of choice before you start bleeding. Bleed until the color of the fluid coming out is the same as the new fluid going in. (This is a little easier with the Motul as it is pretty clear going in - whereas the SRF is dark by definition.)
fjpikul
GT Owner
There are two bleeding points for the clutch. One up higher on the center firewall and one low on the right rear side of the engine.
An easy trick I found in keeping the clutch fluid fresh is to vacuum out all the fluid in the reservoir and replace each time you do a oil change. It will keep fresh fluid in the entire system. The clutch pedal displacement is sufficient that fluid travels from the reservoir all the way to the slave cylinder each press of the pedal, so it stays mixed. Change it every oil change and it will stay fresh. No need to bleed it if you do it this way regularly. If you fluid has gotten old and dark, you need to completely flush and bleed once first.
Indy GT
Yea, I got one...too
I agree with Kendall on this point. Ron likes to tout Castrol SRF which is a fine brake fluid for the penultimate racer. Most of us do not drive our cars at this level and the SRF fluid is by far the most expensive fluid option for any car. There are a number of other readably available fluids at slightly lower “wet boiling point” temperature capabilities and at significantly lower costs. And to interject that Ford did ALL the FGT development work on our car (including extensive track development) on the standard OE DOT3 Ford brake fluid. It actually is a very capable fluid (my notes list it at 500°F dry/284°F wet), is very inexpensive but absorbs moisture quickly requiring frequent changes to keep fluid temperature capacity near the listed dry value.
I think PeterK’s comment on replacement frequency is spot on. Changing the fluid in the brake system as well as our clutch system (to a lesser extent) is by far the more significant action than selecting the most expensive fluid to use. Kendall’s suggested RBF 600 has a listed Dry/Wet temperature capacity of 594/421F which is not too far off the Castrol SRF values of 590/518F while 48% less costly (last time I priced out fluids which do change over time). For additional reference the Ford DOT3 P/N PM-1C fluid (500/284F) is 66% less costly and the very popular ATE Type 200 fluid (536/396F) is 72% less costly. Point is there are many options.
And I echo PeterK’s comment on not using DOT 5 silicon based fluid.
All North American brake fluids for use in our cars must comply with DOT Standard #116: “Motor vehicle brake fluids” which states in paragraph S5.1.14 that any DOT3, DOT4, and DOT5.1 (non-silicon based fluid) must be “colorless to amber”. This is what finally got ATE to pull their very popular ATE Super Blue fluid from the market (it did not comply with this requirement). Thus I am not quite sure what is meant by the comment “the SRF is dark by definition”. The certification requirement is that the fluid is to be colorless to amber, so maybe SRF is just amber relative to colorless observed in other fluids?
Wwabbit
GT Owner
....and buy a PowerBleeder. Makes changing a one-person snap. $60. (order the correct adapter for brake and clutch reservoir). Happy bleeding.
http://www.amazon.com/Motive-Produc...8&qid=1415640718&sr=8-1&keywords=powerbleeder
http://www.amazon.com/Motive-Produc...8&qid=1415640718&sr=8-1&keywords=powerbleeder
MAD IN NC
Proud Owner/ BOD blah bla
Kingman
GT Owner
Brilliant Mike! Thanks.
I bought the Motive, though when I pulled it out of the box, I noticed it was nothing more than the weed sprayers you can get at Home Depot.
It's cool to be able to do a one-manned brake bleed, but it's better to have your bud (ChrisA) help.....with beer in hand.
I bought the Motive, though when I pulled it out of the box, I noticed it was nothing more than the weed sprayers you can get at Home Depot.
It's cool to be able to do a one-manned brake bleed, but it's better to have your bud (ChrisA) help.....with beer in hand.
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I too have built my own, but I use a vacuum pump with a needle control valve, pumping through a reservoir (Glass jars w/ drilled rubber stoppers). That way I can see the fluid at the bleeding point.
PeteK
GT Owner
Some little voice in the back of my mind is nagging me about this statement. I have never heard of anyone boiling clutch fluid before. Brake fluid, yeah, happens regularly. But the clutch slave cyclinder shouldn't be getting that kind of heat. So, lemme ask again, are you SURE you boiled the clutch fluid? Could the symptoms be due to something else, like air in the lines due to low fluid? Do the lines pass over something hot that is causing the boiling? Some other hypothesis? Or does the slave cylinder really get that hot???
DBK, I, and many others witnessed first hand how several GT's experienced boiling brake fluid on a "spirited" group drive up Angeles Crest Hwy several years ago. Perhaps the oddest thing is that none of the GTs equipped with a transaxle cooler had the problem but most of the cars without the coolers lost their pedal somewhere during the drive.
Yes..it seemed a little hard for me to imagine as well but I was fortunate to have The GT Guys beside me at the track to evaluate the issue. Rich and Dennis both had a look at my car and sure enough just as they suggested , a 1/2 hr cool down period saw my pedal come away from the firewall and return to the top. I am guessing that every 4-5 subsequent hot laps required a cool-down lap as the pedal would give a slight indication of play at the top of the travel. I did this for the last few hrs of track day without incident. Deff time to change it out now though.
Kingman
GT Owner
On my old Lotus Esprit Turbo, the clutch line (which was simply a plastic tube) ran alongside and zip-tied to the radiator/coolant line that ran from front to back in the tranny tunnel. I can't tell you how many clutches I went through because of the fluid boiling and the tube expanding. I brought the issue to many Lotus mechanics and they never knew a fix, even though it was a problem shared across the board. It was only when "Forums' started up did I learn of what was happening and the 'fix'.
British engineering
PeteK
GT Owner
And I'll bet that's becuase their brake fluid hasn't been changed in, oh, 9 or 10 years.