Bleed slave cylinder with pneumatic brake bleeder?

[wpurple]

I have air in the line and/or slave cylinder, watched several videos that show to remove the assy to bleed, and thought, why not just use a pneumatic brake bleeder just to suck the air/fluid thru? Am I missing something?

Thanks!

 

[fast_dave]

I have air in the line and/or slave cylinder, watched several videos that show to remove the assy to bleed, and thought, why not just use a pneumatic brake bleeder just to suck the air/fluid thru? Am I missing something?

Thanks!

@wpurple

The Explorer clutch slave cylinder reservoir is the size/volume of a shot glass.

In my experience, a hand operated vacuum pump allows you a lot of fine control of the slave cylinder bleeding process - especially with not running the reservoir dry.

But your mileage may vary - so go ahead and give a pneumatic brake bleeder a shot and do a write up w/ pics!

 

[wpurple]

@wpurple

The Explorer clutch slave cylinder reservoir is the size/volume of a shot glass.

In my experience, a hand operated vacuum pump allows you a lot of fine control of the slave cylinder bleeding process - especially with not running the reservoir dry.

But your mileage may vary - so go ahead and give a pneumatic brake bleeder a shot and do a write up w/ pics!

I was going to have someone keep pouring in the slave cylinder as I use the pump...I was concerned there was a reason why I couldn't find anyone who has done it as it.

 

[poker4me007]

I was going to have someone keep pouring in the slave cylinder as I use the pump...I was concerned there was a reason why I couldn't find anyone who has done it as it.

You can gravity bleed the slave cylinder, that's no problem.
But the problem is usually in the clutch master cylinder (stupid design) it's mounted at an upward angle and the air gets trapped on the top where the cheap plastic master cylinder plunger is, and no way to push it out without removing the whole stupid setup.

 

[MakinJeepsWeep!]

There is a trick you can try and it worked on my mazda, make sure its good and full the slowly depress the clutch then when at the bottom just let your foot slip off the pedal like your moon walking off of it so it snaps up, do it 5-6 times and see what happens! Theory is the sudden swoosh of fluid will sometimes kick the air out. I dont know if it will but it works time to time and its pretty simple if it doesnt work! Good luck!

 

[wpurple]

You can gravity bleed the slave cylinder, that's no problem.
But the problem is usually in the clutch master cylinder (stupid design) it's mounted at an upward angle and the air gets trapped on the top where the cheap plastic master cylinder plunger is, and no way to push it out without removing the whole stupid setup.

View attachment 327117

View attachment 327117

 

[wpurple]

There is a trick you can try and it worked on my mazda, make sure its good and full the slowly depress the clutch then when at the bottom just let your foot slip off the pedal like your moon walking off of it so it snaps up, do it 5-6 times and see what happens! Theory is the sudden swoosh of fluid will sometimes kick the air out. I dont know if it will but it works time to time and its pretty simple if it doesnt work! Good luck!

I will try this trick, I tried bleeding with a pneumatic brake bleeder, and manually bleeding it. No change, I would think that the movement of the fluid would move the air from the system, even if it is stuck on top of the master cylinder.

I find if I make siue the clutch is depressed mashed to the ground I can shift into first with a gentle move. The top of the clutch petal is just a little mushy, thinking that there still is air where described or the master cylinder/slave cylinder is worn. I have not added fluid since I bled the system. I took plug out and inspected the slave cylinder and it seems ok. (nothing dripping)

Manually bleeding defiantly pushed more fluid at a time than using a pneumatic, and thought manually bleeding would defiantly push any air out...??

 

[fast_dave]

I find if I make siue the clutch is depressed mashed to the ground I can shift into first with a gentle move. T

@wpurple

You may not be having a hyd. system issue.

How many miles on your 5 speed manual transmission and has it ever been rebuilt?

As these transmissions get older, even with proper maintenance, the synchros wear and you have to stroke them sweetly to get them to do their job.

For instance, during the frigid winter of Nor-Cal/SF Bay Area (lol), sometimes from a complete stop, I find myself having to do a little rpm rise / "blip" on the throttle while simultaneously having light hand pressure on the shift knob to get the 23 year old 1st gear synchros to mesh up with the speed of input shaft.

Re: Shift lever movement, finesse works better than ham handing it -

 

[wpurple]

@wpurple

You may not be having a hyd. system issue.

How many miles on your 5 speed manual transmission and has it ever been rebuilt?

As these transmissions get older, even with proper maintenance, the synchros wear and you have to stroke them sweetly to get them to do their job.

For instance, during the frigid winter of Nor-Cal/SF Bay Area (lol), sometimes from a complete stop, I find myself having to do a little rpm rise / "blip" on the throttle while simultaneously having light hand pressure on the shift knob to get the 23 year old 1st gear synchros to mesh up with the speed of input shaft.

Re: Shift lever movement, finesse works better than ham handing it -

 

[wpurple]

Truck has 39K miles, transmission fluid changed about 4X over the life. I did tow a small camper many years ago, but fluid has always been good.
Never any indication of worn syncro's from the fluid.
(Yes 39K miles)

 

[MakinJeepsWeep!]

You could have a issue but these are very prone to having air stuck. And my 5 speed Mazda has 255k on it and its my little work horse i did put in a bigger clutch and fly wheel and things but its never been apart, I pulled a 30ft low boy with it from here to dallas got one long piece of steel pipe then took that all the way to lubbock TX took every bit of 2 days there and back but never had a hiccup other than the poor 3.0 was for sure working in 5th so i had to keep it in 4th and about 60-65 so it took a few hours longer than what a bigger truck could have done.

 

[fast_dave]

@wpurple

WOW - 39K for a '97!

OK - well, on "high milers" the 1st gear synchro is the first thing to show wear as you start off w/ it all the time - hence that spit ball shot out the window

Over the years most cases of air being introduced into the hydraulic system occur when clutch jobs are performed and everything is replaced, or when the clutch master cylinders are replaced, so this is an odd one with air being introduced out of no where... Has the clutch fluid ever been flushed over all these years? Clutch fluid is the same as brake fluid - it's hydroscopic, attracts water, and should be flushed when flushing the brake system.

OK - so pressure bleeding didn't work for up, go another route - it's always been successful for me - and that's using a hand operated Harbor freight vacuum bleeder - approximately $25 and use the standard 20% off coupon to bring the price down to $20, (LINK PROVIDED BELOW).

I remove the cap on the reservoir, get under the Ex and pump the hand pump mine way up up to between - 25- and -30, and then open the slave bleed valve a 1/2 a turn, thus allowing an intense & instantaneous vacuum to suck the used fluid out and into the collection chamber.

Keep doing this while topping off the fluid reservoir, and cycle the operation with getting in the cabin, pushing the clutch to the floor, and letting it snap up with a "bang" - hopefully dislodging any air bubbles (as @MakinJeepsWeep! wrote in post #5 of this thread).

Good luck and report back!

LINK: Harbor Freight Coupon Database: Harbor Freight Coupon Database

 

[MakinJeepsWeep!]

fast_dave is correct on all those points and has a good list there of what to do in order. And it is correct that fluid attract water terribly thats why the new stuff is almost clear but over time turns nasty in your system.