REQUEST: DIY Clutch Fluid bleed/swap/replacement.
 

I want to upgrade my clutch fluid and as I understand it, it's very similar to the brake fluid swap, but I'd like a DIY. Somebody here knows how to do this and can help, I'm sure of it. :tup:

There is always the turkey baster method... heard a couple horror stories about people losing clutch pressure by trying to bleed the system (when replacing clutches).

It's pretty simple. The one caveat is DO NOT pump the clutch pedal rapidly. You'll airlock the pump.

1) Jack up the front left side of the car. Follow safe jacking/car work practices.
2) Slide underneath and look at the transmission bell housing. You'll see a hard line come out of it and a little nipple covered with a rubber cap. That's the bleed screw for your clutch.
3) Have someone slowly depress and release the clutch pedal 2-3 times. SLOWLY is the key, with about 2-3 seconds for each complete down/up stroke. On the third downstroke, have them hold it down and call out "DOWN".
4) You (now under the car with an 8mm (if I recall) wrench on the bleed screw call out "OPEN" and gently open the bleed screw and let some fluid out. ONLY KEEP IT OPEN FOR 1-2 SECONDS, then close it again. Call out "CLOSED".
5) Your helper then releases the clutch pedal from the floor and manually lifts it back to the up position. They should then slowly pump the clutch down and up repeatedly with 2-3 second complete strokes until the pressure again builds and the clutch rises from the floor on its own. You're now ready for another bleed cycle (repeat steps 3-5).

You must keep an eye on the clutch fluid reservoir (the small one by the brake fluid reservoir) and top it up occasionally. I usually do about 3 bleeds and then give it a check/top it up. It doesn't take more than about 4-5 cycles to completely flush the system. If you pump the clutch pedal rapidly, you'll froth the fluid and airlock the system. It's painful to fix at that point (need a power bleeder).

Hope that helps.

Helps a lot actually. Thank you. REP!

Ok, so I finally stopped being lazy and decided to swap out the clutch fluid with the good stuff, Motul 600. http://i65.photobucket.com/albums/h2...2F2BABDB62.jpg

The clutch fluid under the hood was pitch black and has piece of who knows what floating in it. My buddy hit the clutch a couple times and held it down and it release a very dark black old fluid from the bleeder valve. We did this maybe 12 times while adding in the new stuff. After the new stuff started draining on my end, under the car, we decided it was good. We then lowered the car and checked under the hood again and the new stuff looked a lot better, BUT there was still black particles floating on the top of the new Motul 600 so I used a blue paper towel to soak up and clean a bunch of it, did that 4 times or so, making sure it didn't go below the "MIN" level, and refilled each time.

The clutch feels great for the 2 miles or so that I used it, very springy and tight it seems. However, I decided to launch the car a couple times around ~3500rpm.

1st Launch: Dropped the clutch from ~3500 or so and wheels spun nicely, 2nd gear went in great, but seemed like the clutch wasn't grabbing well. The car still drove fine.

2nd Launch: Dropped the clutch from ~3500 again and the wheels spun and went into 2nd nicely and then the clutch felt sloppy again. If began to engage just a couple inches from the floor like the problem I was already having after spirited driving. So I took her easy for a mile or so back to the house and by the time I got back home it felt fine again. :icon14:


Any tips or pointers?

Maybe a braided stainless clutch line will help? Or clutch needs to be adjusted?

Alright, just got back from another drive around my community. Without launching the car, I took off kinda quickly and the pedal starting sticking again and I had to pop it back up with my toes. When stopped the car and pumped the clutch I got my clutch pressure back. This is very annoying. I think I'm in the market for an aftermarket clutch/flywheel and CSC setup.

Stainless steel line and/or CSC replacement is in your future.

And I think I might have goofed too. I believe my buddy pumped the clutch too quickly while we were draining it and I might just have air in my lines. I'll report back when I bleed it again tonight or tomorrow.

Using some sort of suction device, I would of emptied out most of the reservoir and refilled with fresh fluid rather than pumping it all through the system.

But agreed, either there's air, or your CSC is beginning to show signs of failure. There really is no clutch adjustment per say, other than changing the pedal heights.

Just changing the reservoir fluid without bleeding the system isn't of much benefit. The fluid that 'count's is in the clutch CSC and master cylinder. It will take a long time (months?) for reservoir fluid to dissociate and mix with the older fluid in the rest of the system. Much better to bleed new fluid through.

@Spearfish, let me clarify. I didn't mean to just suck the old stuff out of the reservoir, refill leave it at that. I meant before flushing/bleeding, to eliminate as much of the old fluid as possible. Probably better for the line and CSC not to have all those contaminates flowing through the system. In fact, one of the install guides for the zspeed heavy duty csc suggests this too.

It would probably be cheap preventative maintenance to do the clutch, trans and rear end fluid annually (~12-15K miles).

Fixed. Bled the clutch again and got the rest of the air out. Works great.

any pics on where the bleed screw for the clutch is??

subscribed i need to read this thread for preference

this!

Here is the image from the service manual. I hope to do this in the next few months and definitely plan to document the process for the forum.

http://i45.tinypic.com/358nr85.jpg

For those looking for pictures underneath. Sorry it took me so long to post them. Follow the clutch line to the transmission and you will see a little black cap. Pull that off and thats the bleed nipple you'll be working with.

http://www.the370z.com/members/wsarv...-cap-black.jpg

http://www.the370z.com/members/wsarv...-black-cap.jpg

dayam is that salt corrosion from the ocean? yikes...

Probably. I think the car came from the Carolinas and more than likely has seen some salty roads. There's also a little rust here and there but nothing I haven't seen on other vehicles. But I bet that's why I had such a hard time getting the stock exhaust off. I had all 4 bolts siezed up at the cats and ended up using those extractor sockets along with a blow torch. Was under the car for the entire day sunrise to sunset wrestling with those suckers.

Any video for this DIY?

Anybody change there break and clutch fluid when it still looks clean and is full in the resivour and notice a difference in the clutch? My clutch feels like it has half the peddle length to the floor than it normally does,but only in the morning after the car sits all night. At first it would do it once in a while,but now is a common occurrence. I'm thinking that it has absorbed a bunch of moisture,so it's lost its ability to keep pressure. After about ten minutes it's fine. I got the car last October so I don't know when the fluid has been changed,or if at all. I bought fluid anyways and will be bleeding the system for piece of mind,but was curious if anybody has ran into these symptoms with the clutch and looked to have decent and clean fluid.

sub'd. doing this this weekend!

Can this be done with a motive pressure bleeder? Similar to bleeding brakes?

The FSM specifically says NOT to use them :twocents:

Thanks!

Gravity bleeding works real well. Suck out most of the old with a syringe, then refill to the top, open bleeder at the bottom a turn or two, then monitor to to make sure it doesn't run dry.

You can use a helper at the end to pump the pedal a few times and do a traditional bleed. Not really necessary if there's no problem to begin with and it's just preventative maintenance being done.

just curious how long does it take to drain out all the fluid from the clutch fluid reservoir?

When I did mine, i'd start refilling it when it got to the low mark. Went through 4 or 5 repetitions like this. It wasn't gushing out the other end, but definitely coming out. I'd say it took a good 30 seconds (or more) to go from almost at the top to the low mark.

I used about half of a 12oz bottle. Keep in mind, clutch fluid capacity is very minimal to begin with.

Good to hear. I was wondering if this could be done by yourself since I don't always have friends available to assist with a traditional bleed.

that's fairly quick. did you have to do anything to initiate the process or just loosen the bleed valve and let it drip?

Gravity! It's wonderful.

Mine was dirty as hell, took an hour and some change

I'm planning to gravity bleed the clutch fluid in the next week or two. I was shopping for fluid and I came across these two. Is one preferred over the other?
1. https://www.amazon.com/RBF-600-RACNG...ords=motul+600

2. https://www.amazon.com/dp/B004LEYJO4...I1BP7RXTK07LSG

Unless you're tracking the car, I really don't see a need to use a high performance fluid.

Both appear the same, just different packaging labels.

Btw, give this video a look - MotorvateDIY Video: Clutch Fluid Change - MyG37

Read the thread too, good point about why gravity only bleeding is insufficient.