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Slave cylinder trouble

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Dee1986

Slave cylinder trouble

I'm having no luck getting my clutch slave cylinder to bleed. I just put everything back together after replacing a tore up ring gear and all went smooth. Last thing to do was pop the slave cylinder back in and call it done. I've pumped and bleed this thing for an hour and can't get the clutch pedal to build pressure or return from the floor. What am I missing?

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

Gary Lewis

Re: Slave cylinder trouble

Administrator

I'm going to ask a question that suggests I think you are ...... inexperienced. But I don't mean it that way. And I'm sure you are smarter and more experienced than I.

But, you do know that most master cylinders have a rubber liner under the lid, and you are supposed to remove it and put the fluid under that?

I ask because when I got Big Blue the clutch didn't work well. I bled and bled and then they didn't work at all. But I'd not pulled that liner and all of the fluid was on top of it and the master cylinder was dry.

Once I pulled that and added fluid then bled again I still didn't have enough pedal to release the clutch. But the guys told me that the line is so small on a clutch that the bubbles don't come up it without being jarred. Instead they stick inside and compress when you try to use the clutch.

Sure enough, I started the truck in gear and drove around the neighborhood for maybe 2 miles, all the while working the clutch pedal. And by the time I got done I had plenty of pedal.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

ArdWrknTrk

Re: Slave cylinder trouble

Administrator

In reply to this post by Dee1986

460 clutch slaves can be obstinate like that.

Unfortunate thing, the plastic slaves have no bleed nipple.
Backfilling from there would likely have it done in a heartbeat.

Gary's right though.
I never get a 'good' pedal until it's been driven

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Dee1986

Re: Slave cylinder trouble

In reply to this post by Gary Lewis

Yes I am aware of and pulled the liner. No worries about the question though, none of us were born with all the answers. I've bleed plenty of brake systems before, and am puzzled as to why they didn't put a bleed nipple on this thing so I could simply put a tube on it and pull the air through. I've currently got a pedal that hits the firewall and has no spring back or pressure. I tried pulling air up through the master but the hole in the bottom of the resivoir is no good for my hand pump nipple to fit in. I had to walk away from it tonight and I'll try and wrap my head around it tomorrow. Happy Easter

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

ArdWrknTrk

Re: Slave cylinder trouble

Administrator

Brian,
All I can say is that at one point I did have an aluminum slave that does have a bleed nipple just like a brake caliper (I think I do still have it , in a box or tote somewhere)

Maybe it was a 351 application?
IDK, but it was great.
I kept it in hopes of a rebuild, but when I need a clutch, I need it NOW.

The other solution with that one is to run tubing up, and into the master.
Fill the tube and just keep cycling.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Rembrant

Re: Slave cylinder trouble

In reply to this post by Gary Lewis

Gary Lewis wrote

Sure enough, I started the truck in gear and drove around the neighborhood for maybe 2 miles, all the while working the clutch pedal. And by the time I got done I had plenty of pedal.

I remember going through this process. I have a homemade continuous brake vacuum bleeder, so I remember sticking it on the slave bleeder screw, and then I ran enough fluid through the system to fill it probably 3 or 4 times, while pumping the pedal as much as I could. Probably 3 or 4 sets of pumping it 20 times. After that I had some pedal, and like Gary I went and drove it around a bit and it got better with some more shifting. I haven't touched it since but the pedal is good and hard now.

1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

Dee1986

Re: Slave cylinder trouble

I'm gonna take the bleed screw out of the slave and shove my bleed hand pump down in that hole and try that route. I've ordered a new slave that has a proper bleed nipple to have just in case I have to go that route. Thanks for the guidance so far. If I can get just a little pedal action out of it I'll try driving it around like y'all stated.

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

Dee1986

Re: Slave cylinder trouble

Thanks for the tip, I took the allen screw bleeder all the way out and pulled vacuum through there and about four cycles of topping off the master before it got too low pulled all the air out and now I have a somewhat decent pedal. It's amazing how much air you get out of a small system. Thanks again, enjoy your Sunday. Ham dinner with just my wife and I is going to seem a little strange without a house full.

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

Gary Lewis

Re: Slave cylinder trouble

Administrator

Glad you got some pedal. It'll get better from here. (I'd say "Ride up with wear" but you might not be a fan of Are You Being Served?)

As for the ham and just the wife, that's exactly our situation. We thought our kids were moving in with us for a bit and bought a large ham. They haven't yet, so now we are eating ham. Lots of it.

Gary, AKA "Gary fellow": Profile

Dee1986

Re: Slave cylinder trouble

Big fan of Mr. Humphries and the gang. That was some classic British comedy. Thanks again to all

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

Gary Lewis

Re: Slave cylinder trouble

Administrator

I'm free! Yes, that was classic. We are big Britcom fans.

Gary, AKA "Gary fellow": Profile

ArdWrknTrk

Re: Slave cylinder trouble

Administrator

In reply to this post by ArdWrknTrk

Pic, to prove it exists

https://www.flickr.com/photos/24183730@N03/8654301895/

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Dee1986

Re: Slave cylinder trouble

That bleed nipple would have made the whole process alot simpler. I ordered a new slave that looks pretty similar, I'll save it for the next time I have to do anything to the hyd system.

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

ArdWrknTrk

Re: Slave cylinder trouble

Administrator

Just force fluid from the nipple to the master.

Let us know what it is and where you got it

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

reamer

Re: Slave cylinder trouble

Bleed the system off-the-truck, this is what I did by myself, and it gets done in 10 minutes.
Remove the master, line and slave (if you have the out-side style)

Attach the master on top of a 6' ladder, with line attached and the slave attached. (if the slave is around the input shaft, Just the master and line will do, but add a weight is the whole line is vertical.

Fill the master and open the bleed on the slave (if one).
Slightly tap the line from bottom ( slave area) to the top.

Watch the bubbles form in the master... keep adding fluid as the master cylinder fluid gets lower... Slightly pump the master and tap the line, over and over again. till the master cant be pumped any more.

Then remove the system from the ladder and put the master in a vise, (line end lower) pump and tap till the rod can only move about 1/4"

Install master cover.

Now install the bled-system to the truck.
slide the closed line (or slave cylinder) down the fire wall Connect the master and then connect slave.
Done!
There are videos on this...
Works!

1986 F-150 Flareside 4x4, 351, 4-v, ZF5 speed. AC, Cruise, Tilt, Slider, Digital clock, Radio, Lariat seat, Pwr doors/locks

Dee1986

Re: Slave cylinder trouble

In reply to this post by ArdWrknTrk

It's supposed to be on my front porch before the weekend. I'll post more info on it once I can do an unbox and bench review.

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

Dee1986

Re: Slave cylinder trouble

In reply to this post by ArdWrknTrk

Just showed up.

It seems to be decent quality aluminum casting. Came with new bracket, seal, and split pin. It's probably better than the factory plastic slave, at least it's got a proper bleed nipple

Brian,
1986 f250 xlt lariat 4x4/ 460 4 speed
2016 super duty lifted
1949 Ford custom sedan, orig flathead eight

ArdWrknTrk

Re: Slave cylinder trouble

Administrator

Brian, thank you for sharing the PN and manufacture.
Exedy is fine quality friction components in my experience.

If I ever have to replace my slave, I'll know what to buy, thanks to you!

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.