Removing transmission

This was seen in the mechanical systems as your pedal's "freeplay". When air is left in the system the air can warm up and expand causing the fingers to ride the bearing.

. .

Al =3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D MarshMonster replied:

The slave does not back off the "throw out" arm. It stays in contact with it. (Release Arm)

A spring placed BEHIND the apply piston inside the slave keeps the piston forward, pushing forward the apply rod, against the release arm, moving the release bearing forward on the bearing retainer, which rides in contact with the pressure plate......AT ALL TIMES, unless the systems fubar'ed.

~:~ MarshMonster =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Thank you for trying to understand this crap design.

So, the engineers think it's OK to have the throw out bearing spin continously. That's why they don't last as long as they used to. In the interest of lower cost, the engineers have again screw us with a poor design.

If the hydraulic system had a spring like Budd said there would be no way to control free play. it would just "return" the slave all the way in. Al =3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D

yer welcome, it's my job to understand it.

Let's not get started on engineers.... dey got big egos and are lurk'n about ready to defend their idiotic reasonings at all times.

Eventhough I have found many errors in Budds advice....I don't recall him posting the spring thing on a hydraulic set up in this thread. But I'm gonna re-read the thread to find out if he did....and if he did.......we'll see if we can't keep the thread lively....lol.

~:~ MarshMonster

You want to remove a cast iron Powerglide laying on your back - NOT. I was a skinny 16 year old and the tranny weighed more than I did.

Generally not enough pressure to cause the bearing to spin all the time - just rub gently and slowly rotate.

And you would need to adjust the clutch, just like on a mechanical system. SOME hydraulic systems actually do work this way. Spring and all.

-------SNIP-------

PowerGlide! Try a 49 Olds or Caddy Hydromatic. Weigh more than both of us.

Al

Al, answers to yer questions......

1) I have pulled a hundred or so Mopop standards 4x4s.

2) The first one caused a couple skint knuckles....... the last one was a breeze....(2 days ago)

3) as already stated by others in the thread...... YES....seperate the t-case from the tranny.

(2) You end up with a gag-awfull shudder because the flywheel looked good "To You"....so you you scrimped and didn't have it machined.

Very good description of all the work required, Marshy. I am just a bit curious about the need to have the flywheel resurfaced each time. My reason for this is that I used to have a '74 Ford 3/4 ton with an NP435? 4 speed in it. The first time I had to change the clutch, which was shortly after I bought it with 115k on it, I found the flywheel had deep grooves in it from the previous owner wearing the clutch down to the rivets. I didn't bother having the flywheel resurfaced. (young, no money, didn't care.) I had no shudder from the clutch due to the worn flywheel surface. Over the years, I did experience a couple of occasions when the clutch would shudder, but each time on disassembly I found it was because a couple of springs on the clutch plate itself had broken. I beat the hell out of that truck, too. I would put a choker around a log in a log deck, hook it to the ball on the hitch, put the truck in granny and give 'er the gas. Sometimes the back end of the truck would get jerked 3 feet to the side trying to get that log out. I have no doubt that this is what would damage the clutch plate. In each instance of shudder, I found the clutch plate itself had a couple of broken springs, but the plate itself had very little wear on it. I put another

135,000 hard miles in 16 years on that truck before I bought my '03 Dodge. And the last time I changed the clutch on it, the grooves on the flywheel had smoothed out to just light waves on the surface, and there was no shudder. Have things changed so much that a new surface on the flywheel is critical to smooth operation of the clutch? I can understand how a glazed surface would contribute to clutch slippage, although that old flywheel had almost a mirror sheen and was still just fine. :) HD

Set your own clothes on fire....

Budd was correct: Air in the line has an adverse effect on bearing release. Air in itself can act as a spring, as it compresses nicely, and decompresses just as well. Expansion and contraction due to heat is debatable, in that the effects could vary from none to more than enough to cause the bearing to wear more quickly than normal, depending on a circus full of variables.

Budd was correct: There should be a fraction of an inch of freeplay in a mechanical system. In a hydraulic system, not so likely.

That means I'm entirely correct, since you agree completely with that statement.

Assuming there is one, thats true. But there is not always a spring behind the slave cylinder piston. Secondly, the sole purpose of that spring is to be sure that the piston is fully extended to the clutch fingers at rest, so only a single stroke of the clutch pedal is needed to release the clutch. Its effects on wearing the throwout bearing are almost as negligible as that of gravity on the throwout bearing.

As such, if you are saying it has any negative effect on the throwout bearing, you are incorrect.

Try reading what Budd said. He mentioned nothing about the clutch. Simply said that an improperly bled system could result in faster than normal throwout bearing wear. That is not only possible, its probable.

I'm sorry, I didn't catch how many years of hydraulics experience you have and how many years of mechanics you've worked.

10 years heavy equipment mechanic/ journeyman millwright, 30 years small engine mechanic.

Yep, both automotive experience and hydraulics in one low cost package.

-- Budd Cochran

WARNING!!!

Poster still believes that intelligence, logic,

common sense, courtesy, and religious beliefs

are still important in our society, and might include

them in his posts.

This was seen in the mechanical systems as your pedal's "freeplay".

When air is left in the system the air can warm up and expand causing the fingers to ride the bearing.

-- Budd Cochran

=========== =========== "Budd Cochran" wrote in a seperate message:

However, an improperly bled hydraulic clutch can, when the system gets warm from under the hood heat, HOLD pressure on a throwout bearing . . .just like it would be if you rode the pedal.

-- Budd Cochran

It is assumed that as long as the pressure is light (gravity feed of fluid is very light) it will have little effect on th clutch.

-- Max Give a man a match, and he is warm for a short while. Light him on fire, and he is warm for the rest of his life.

========= =========

Here Max, hold still....while i set yer shirt tail on fire......

Budd was wrong on so many levels..... and now your endorsing him.

You on the other hand...are only partially wrong. The effects of gravity have nothing to do with the bearing apply. It's the effect of that spring jammed in behind that "slave cylinder apply piston" that hold it all togeather.

like it was designed to do.

~:~ MarshMonster ============= =============

The master cylinder is above the slave cylinder. Gravity would put some pressure on the slave cylinder.

I don't see any way for the slave to back off the throw out arm.

On an old truck with mechanical linkage, there are two springs to keep the throw out bearing off the pressure plate fingers. And, when adjusted correctly, it works. Al ========= =========

The slave does not back off the "throw out" arm. It stays in contact with it. (Release Arm)

Why..??....because if it didn't ..... it would fall out the ball seat on the release arm and when you stomped down on the clutch pedal the rod would shoot out into the bellhousing.....and the slave cylinder piston would come blowing out. Which would be a nasty thing and quite the inconvenience to repair all the time.

ROTFLMBO!!! Got news for you, friend. There are many hydraulic pushrod / socket arrangements that have slack in them . . .Ya just need a socket made a little deeper or a soft rubber retainer to hold them together . . .look at the brake pedal push rod if you need proof. And before you cackle again, the hydraulic pressure on this rod is from the return springs on your braking system pushing it back up after a brake application..

A spring placed BEHIND the apply piston inside the slave keeps the piston forward, pushing forward the apply rod, against the release arm, moving the release bearing forward on the bearing retainer, which rides in contact with the pressure plate......AT ALL TIMES, unless the systems fubar'ed.

That setup is wrong. The spring has to return the piston.

The spring tension of the Pressure Plate works against the spring tension of the Slave Cylinder apply piston.........

And your throwout bearing gets the bejesus worn out of it in short order.

and....wah..lah......

It's "voila!" (Fr) [Phonetic: v-wa-la], genius. oh, btw Miss Piggy doesn't say it right.

no hydraulic pressure..... Jest an ole timey mechanical spring and arm set up........in a fancy package.

Bwah-ha-ha-ha!!!!!

Can you figure out why the piston can move in and out at over 1500 rpms without creating hydr. pres. that would actually cause the clutch to apply?

Uh, strokes, which are what a piston does are not measured in RPMs, but strokes per (minute, second, day, year, millennium; pick one)

~:~ MarshMonster ~has to go work on his truck....got to get that brake master cylinder below the level of the calipers~

Well, if your driving is anything like your knowledge, then just head for the nearest sharp curve and you'll get the master cylinder below, above, below, above, below . . . .

Uh, Al, they make adjustable pushrods, don't they? Besides, one advantage to a hydraulic setup is the ease, or lack of need for, adjustment. With a hydraulic setup, everything can be slammed together at the factory, bled with a pressurized filler and sent down the line.

-- Budd Cochran

WARNING!!!

Poster still believes that intelligence, logic,

common sense, courtesy, and religious beliefs

are still important in our society, and might include

them in his posts.

When air is left in the system......... there is NO WAY IN HELL it will EVER warm up and expand causing the fingers to ride the bearing......especially being as the bearing is already riding on fingers.

a question........... if the air COULD....expand due to heat and apply the bearing.....

then why isn't the fluid expanding and applying the bearing????????

air compress's brake fluid DOES NOT

Air expands when heated, most fluids do not . . . or have you forgotten how a hot air balloon works ( generally taught by the time you get to the third grade).

-- Budd Cochran

WARNING!!!

Poster still believes that intelligence, logic,

common sense, courtesy, and religious beliefs

are still important in our society, and might include

them in his posts.

~:~ MarshMonster ~sips his axle grease~

Not a hydraulics expert, are you?

-- Budd Cochran

WARNING!!!

Poster still believes that intelligence, logic,

common sense, courtesy, and religious beliefs

are still important in our society, and might include

them in his posts.

-- Budd Cochran ================= =================

That's not possible.

the clutch WILL NOT apply under any scenario resulting from an improperly bled system.

Never... Ever...

~:~ MarshMonster

Liquid does expand when heated. This is high school physics. That's why hot water rises, or classifies. You're confusing this with compressing liquids. We were taught you can't compress liquids, and even that is false. Under enough pressure it will compress. Ever hear of hot ice?

Al

I am not sure that this is exactly what Budd either said or meant but if YOU actually believe this Max, prove it because in reality, you are dead wrong. There is no way in hell that an improperly bled system could cause excessive wear to the bearing but it is highly probable to cause excessive wear to the clutch. I don't claim to be a hydraulics expert but there are some simple facts that seem to be completely distorted.

First of all, gas, liquid and solids ALL expand to some degree when heated with the difference being that liquids and solids apply EXTREME pressure when any expansion occurs and gasses do not unless the expansion is significant. The reason why there is a slight gap required in a mechanical clutch linkage is due to the possible expansion of the mechanical parts partially engaging the clutch and causing excessive wear and slippage to the clutch, not the bearing. The return spring serves to stop the linkage from rattling when in full release due to the required gap as much as anything else.

As for gravity, the weight of the fluid is so insignificant in a 3/16 line that I doubt that it could supply enough force to even move the clutch slave cylinder at all, never mind move it with enough force to cause excessive wear on the bearing.

Air in the system will also not cause the slave cylinder to move because if it expands, all it will do is push the fluid back into the master cylinder reservoir as at full release, the ports between the master cylinder and the reservoir are open, pretty much just like the brake master cylinder. It does however, have the ability to cause excessive clutch wear because it could prevent the clutch slave cylinder from moving enough to fully disengage the clutch when required due to its compressibility.

As for the bearing wear, I would think that it goes through as much wear sitting at a single traffic light while holding the clutch in as it does with a year of wear with the light to non-existent pressure being placed on it during normal driving when the clutch is fully engaged. It sounds like the OP simply has a bad bearing, possibly contaminated with dirt during assembly causing excessive wear and premature failure.

If you have to ask this type of question, it is out of your league. Hire a pro!!

With a hydraulic lifter, I assume that's what you're talking about, you want a light pressure on the valve to keep the lash to zero. We are talking about a throw out bearing rotating when the engine is running. It's not the same.

We were taught NOT to have pressure on the bearing all the time. Hence the free play adjustment. That's what we're discussing. Apparently the engineers decided to reduce the cost of the clutch linkage, they would just sacrifice the throw out bearing. Another example of this fine engineering is the new Dodge truck 4X4 front axles, with no disconnect. What the Hell, it don't cost them money to drive the axle all the time, it saves it. We however get to pay for it every day. Just like in the old days when full time 4 wheel drive came and went. By the way that was another Chrysler design.

Al

No, Al, the rod that pushes the piston in the master cylinder or the rod that pushes the clutch arm or the rod that pushes Curly off the Three Stooges boat is a push rod.

Bearing design, metallurgy, even the lubricants used today are much different than just 10 years ago.

But if the rod is retained with a simple synthetic rubber ring in the socket on the piston on the slave cylinder, a light spring used to ensure retraction, there can be a freeplay clearance.

No pressure all the time? Well, gee, how do wheel bearings last 100K, axle bearings, . . . .Al, even when not rotating, bearings have pressure on them of some kind.

Yep, and it actually worked well as designed, drove them in the military, but gas mileage was destroyed. Right now there's a 78 Dodge sitting at parts store for sale for $1200 and it's a full time 4X4. From what I can find out the only problem with it is . . .gas mileage.

Budd

No, Al, I am not confusing compression with expansion, and I'd appreciate it if you'd quit talking down to me like I'm a kid. The hot air rises for the same reason as the water, CONVECTION, but hot air also EXPANDS.

-- Budd Cochran

WARNING!!!

Poster still believes that intelligence, logic,

common sense, courtesy, and religious beliefs

are still important in our society, and might include

them in his posts.