New clutch master cyl. needed?

[DMC81]

I recently got it to my "D" to move it and the pedal went to the floor. I noticed the clutch res. was low so I filled it to the correct level and now the fluid shoots out the hole on the cap. I was told to replace it, is that correct? If so is it hard to change out? Any tips?Thanks.

[LEVY]

I recently got it to my "D" to move it and the pedal went to the floor. I noticed the clutch res. was low so I filled it to the correct level and now the fluid shoots out the hole on the cap. I was told to replace it, is that correct? If so is it hard to change out? Any tips?Thanks.

Seems like all you need to do is to bleed the system.

LEVY

[DMCMW Dave]

Seems like all you need to do is to bleed the system.

LEVY

If you bleed it, it may actually fix it for a while. Until it leaks out again. They don't typically get air in them from nowhere. If air got in, fluid went out, and it went somewhere. Usually somewhere bad.

[LEVY]

If you bleed it, it may actually fix it for a while. Until it leaks out again. They don't typically get air in them from nowhere. If air got in, fluid went out, and it went somewhere. Usually somewhere bad.

Unless something else is wrong with the slave!

LEVY

[DMC81]

Unless something else is wrong with the slave!

LEVY

I cant find a leak anywhere, I think it was just setting so long.??

[Tillsy]

I cant find a leak anywhere, I think it was just setting so long.??

It had to go somewhere - either someone stole your fluid or it leaked, the leak being more likely ;)

[David T]

If you haven't found the leak it is because you have to keep looking! Try under the carpet on the driver's side or on top of the transmission. If it leaked out figure on replacing the clutch master and slave cylinders and if you still have the red plastic hose, replace that too with a S/S braided hose. While you are at it look at the brake master cylinder. If the fluid is dark and thick in there figure on rebuilding the whole brake system too. British cars do not like old brake fluid (clutch fluid is the same thing). If it is not flushed at least every other year it gets corrosive and attacks the metal causing pits. When the seals move over the corrosion it tears them up and then everything starts leaking. Bleeding will get you going very temporarily, till it leaks out again.
David Teitelbaum

[stevedmc]

When the stoppers at the end of their master cylinder piston assemblies go bad, failing to seal off their reservoirs and allowing their master cylinders to push fluid back into their reservoirs and out the holes in their caps rather than moving their slave cylinder pistons, Steve Rice and Bill Robertson buy Fenco #22320 replacement piston assemblies at Autozone for $15 apiece.

Steve Rice and Bill Robertson see no reason to replace an entire master cylinder when only a small piece of rubber about 1/4" diameter -- the reservoir stopper -- has gone bad. If Autozone would sell them that piece of rubber alone for a dollar, rather than making them buy a complete piston assembly for $15, they could save even more money.

[DMC81]

If you haven't found the leak it is because you have to keep looking! Try under the carpet on the driver's side or on top of the transmission. If it leaked out figure on replacing the clutch master and slave cylinders and if you still have the red plastic hose, replace that too with a S/S braided hose. While you are at it look at the brake master cylinder. If the fluid is dark and thick in there figure on rebuilding the whole brake system too. British cars do not like old brake fluid (clutch fluid is the same thing). If it is not flushed at least every other year it gets corrosive and attacks the metal causing pits. When the seals move over the corrosion it tears them up and then everything starts leaking. Bleeding will get you going very temporarily, till it leaks out again.
David Teitelbaum

So when I crack the bleeder and bleed it out it will stop shooting out the cap? Sorry im just new to the whole fluid shooting out of the cap thing.

[stevedmc]

Steve Rice and Bill Robertson know that it is much easier for a master cylinder piston to push fluid back into the reservoir than it is to disengage a clutch, which is the whole purpose of the reservoir shutoff stopper -- to seal off the reservoir so that the master cylinder piston has no choice but to push fluid to the harder task.

Steve Rice and Bill Robertson know that if the reservoir shutoff stopper goes bad, the master cylinder piston will do just as you say: it will push fluid back into the reservoir until the reservoir is full and fluid shoots out the hole in the cap.

[DMCMW Dave]

So when I crack the bleeder and bleed it out it will stop shooting out the cap? Sorry im just new to the whole fluid shooting out of the cap thing.

No. If it is bad you can bleed it all you want and it won't work.

[stevedmc]

http://sphotos-a.xx.fbcdn.net/hphotos-ash4/s720x720/307818_454462807932308_287453354_n.jpg

[DMCMW Dave]

[a huge picture]

Unless your master cylinder bore is pitted from long exposure to moisture.

[David T]

Typically if either the master or slave is leaking BOTH of them are corroded and both should be replaced at the same time. Otherwise you are just going to have another problem soon with the clutch and have to bleed it all over again. The hose should also be changed if it is the red plastic one, again, to avoid having to bleed the system multiple times.
David Teitelbaum

[stevedmc]

OP stated in Post #5 that the master cylinder is not leaking. If the cylinder is pitted it will indeed damage the piston seal and leak out the front. If the front is dry, the cylinder most likely is not pitted (at least where the piston seal passes by).

Fluid shooting out the cap is caused by the reservoir shutoff stopper not working. That can be caused by pitting where the stopper seats, but until you remove the piston assembly and look inside the cylinder you won't know. It can also be caused by failure of the stopper (rubber tip), or by failure of the rod that slides inside the piston.

[David T]

Unless you know one of the cylinders was recently replaced, if the system is leaking the best thing to do is to just change BOTH. Especially if the fluid is dark and thick. Yes, sometimes you can clean things up and save them but till you take it all apart, find the parts you need etc, it is just a whole lot easier and faster to replace them. Once you do replace them you can see if it is possible to rebuild the old parts and keep them as spares.
David Teitelbaum

[LEVY]

If it ain't broke, don't fix it!

LEVY

[stevedmc]

Or take the master cylinder off, clean it out with some extra fine grit sandpaper *AROUND THE CIRCUMFERENCE, NOT FRONT TO REAR*, lubricate it with a little brake fluid, stick a new $15 piston assembly in, reinstall the cylinder in the car (hint: weld tabs onto the heads of some 3/8" bolts that will catch on the cylinder and hold the bolts still while you tighten their nuts), bleed the system, and see if that fixes the problem.

[David T]

It's great for you to be so optimistic and try to save everyone some money but in my experience most owners do not flush the brakes (and clutch) often enough. By the time things start leaking and the pedal goes to the floor it takes more than a little sandpaper and $15 worth of parts and a little brake fluid to get the car going again. Not everyone wants to go through taking things out, fixing it, putting it back in and finding it still leaks. Also not everyone is as handy as you are and wants to fix their old parts. It is all they can do to just replace them. IMHO the best advice is to replace the cylinders and if they are so inclined they can have the old stuff rebuilt for spares (or rebuild it themselves). I know this may not make sense to the Bill and Steve team but most owners are not as mechanically inclined as you guys.
David Teitelbaum

[stevedmc]

You act as if just because some owners may be unable to install a replacement master cylinder piston assembly (curious inability if they can replace the master cylinder altogether...) it should not even be mentioned. That kind of thinking leads to $25K DeLoreans. You can not drive 10,000 miles per year with only $500 maintenance by doing wholesale component replacement.

Just for the sake of argument, let's assume the OP has never diagnosed a bad master cylinder piston assembly and replaced it -- should he now be denied the opportunity to learn to do so? If the OP chooses to replace the entire master cylinder, so be it. If he chooses instead to replace the piston assembly alone, he has been provided not only a suitable part number, but also the procedure. That *IS* how inexperienced owners become experienced ones....

[David T]

You are right, as a learning experience it is a LOT better to take old parts out of the car, clean them up, find repair kits or whatever to fix them up, and put them back in. Maybe several times. It can also be a lot cheaper. It DOES take a lot more time but when you are through you are all the better for the experience. I have done it and so have many others. Not all owners are so inclined. They have a problem with the car and want to fix it themselves as fast and as easily as possible. In fact, many have very little experience or knowledge or tools and are stretched to their limits just getting the old parts out and the new parts in. When you fix your old parts they may not be as reliable as the new parts you can buy and so may not last as long. A lot depends on your skill level. For the unskilled, replacement is the best advice unless they choose to improve their skills and have the time and tools to do the job. The consequences of saving a little money here can be an expensive repair in the transmission if you mess up and drive the car on a bad clutch.
David Teitelbaum

[LEVY]

It is easy to recommend new parts when you are working on some one else's car and spending some one else's money!

LEVY

[David T]

Yes, it is easier. But consider this, when a shop does the work they have to guarantee it and if the part goes bad they have to R & R it at their expense. It also takes them time to rebuild it and they may not be comfortable guaranteeing the part after that. It is faster to just R & R parts so the car gets back to the customer faster. If you do your own work and spend your own time on it, it is a whole different story. As was pointed out you may also be doing it for the learning experience and to expand your skills. Most shops have seen how the story ends when you try to save the customer some money. You just do the master cylinder and a couple of months later the slave starts leaking or vice-versa. The "honest" shop will tell you all of the bad news up front and try to convince you to do the whole job at the same time which in the end will save the customer money. If the bores of the cylinders are very pitted you are not rebuilding them unless you sleeve them. Between the time it takes to send them out and the expense, it doesn't make sense to rebuild the old junk. Not when you can get new stuff cheaper. In most cases you are not going to be able to save the cylinder with a piece of sandpaper or a hone.
David Teitelbaum

[LEVY]

Yes, it is easier. But consider this, when a shop does the work they have to guarantee it and if the part goes bad they have to R & R it at their expense. It also takes them time to rebuild it and they may not be comfortable guaranteeing the part after that. It is faster to just R & R parts so the car gets back to the customer faster. If you do your own work and spend your own time on it, it is a whole different story. As was pointed out you may also be doing it for the learning experience and to expand your skills. Most shops have seen how the story ends when you try to save the customer some money. You just do the master cylinder and a couple of months later the slave starts leaking or vice-versa. The "honest" shop will tell you all of the bad news up front and try to convince you to do the whole job at the same time which in the end will save the customer money. If the bores of the cylinders are very pitted you are not rebuilding them unless you sleeve them. Between the time it takes to send them out and the expense, it doesn't make sense to rebuild the old junk. Not when you can get new stuff cheaper. In most cases you are not going to be able to save the cylinder with a piece of sandpaper or a hone.
David Teitelbaum

Yes David, I know all that, I own a business and I charge $120.00/hr. Don't know how much you charge but if you do the work, most of the time it would be even cheaper for the customer to pay for a new part than pay you to rebuild it.

The point here is, some people would try to do it themselves to save a few bucks and also to learn some new skills, nothing wrong with that, right?


LEVY

[stevedmc]

If any owner wants to replace the entire master cylinder, but doesn't want to pay vendor prices, AMC used the same Girling clutch master as DeLorean:

http://sphotos-b.xx.fbcdn.net/hphotos-snc7/402645_455028347875754_990671097_n.jpg

(Pedal push rod is different -- transfer your old pushrod to the new cylinder)

[David T]

There is nothing wrong with anyone trying to expand their skill set. I encourage it. I also try to explain to them to be realistic. You need a proper place to work and some tools. A lot of patience and willingness to get dirty and maybe have to do the job more than once till you get it right. Some of us don't have the time, some don't have anyplace to work, etc. No sense taking the car apart if you can't put it back together! There are plenty of posters on this forum that can help the owners with different advice on what to do, where to get parts, etc. It is up to the reader to decide on what advice best suits their needs. There are even posters here that will travel and physically help other owners in distress. It comes down to what the reader wants to do. It is VERY easy to spend money if you have it. Not everyone has enough to spend on their car and wants to know the less expensive ways to fix their problems. I just want them to know the pitfalls so once they decide, they know what they are in for. The worst thing is when they take the car apart and now can't put it back together or start a project and don't have the money to finish it. By knowing what has happened to other owners that had these problems they can make a more informed decision.
David Teitelbaum

[LEVY]

If any owner wants to replace the entire master cylinder, but doesn't want to pay vendor prices, AMC used the same Girling clutch master as DeLorean:


(Pedal push rod is different -- transfer your old pushrod to the new cylinder)



Loved by many.

Hated by few!

God job finding crossover parts!


Now, what is the part number?
Or the exact vehicle.
LEVY

[DMC81]

You are right, as a learning experience it is a LOT better to take old parts out of the car, clean them up, find repair kits or whatever to fix them up, and put them back in. Maybe several times. It can also be a lot cheaper. It DOES take a lot more time but when you are through you are all the better for the experience. I have done it and so have many others. Not all owners are so inclined. They have a problem with the car and want to fix it themselves as fast and as easily as possible. In fact, many have very little experience or knowledge or tools and are stretched to their limits just getting the old parts out and the new parts in. When you fix your old parts they may not be as reliable as the new parts you can buy and so may not last as long. A lot depends on your skill level. For the unskilled, replacement is the best advice unless they choose to improve their skills and have the time and tools to do the job. The consequences of saving a little money here can be an expensive repair in the transmission if you mess up and drive the car on a bad clutch.
David Teitelbaum

I went ahead and ordered the whole thing new, I figure it saves me time and I know its good to go. Im not one who has tons of cash but I feel new is better if it is an option.

[stevedmc]

Loved by many.

Hated by few!

God job finding crossover parts!


Now, what is the part number?
Or the exact vehicle.
LEVY

Clutch master cylinder rebuild kit
Part# 22320
Cross ref vehicle: 1981 AMC Spirit 4.2L 2BL 6cyl

http://www.rockauto.com/catalog/moreinfo.php?pk=966199

[stevedmc]

AMC clutch master in its native environment (you want the one with a remote reservoir):

http://sphotos-b.xx.fbcdn.net/hphotos-ash3/s720x720/579740_455105727868016_1965607530_n.jpg

Also visible are tabs welded to the mounting bolts to hold them still while you turn the nuts from inside the car.