The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Bad master cylinder on my 62??

Evertime my truck sits for more 2 days all the break fluid leaks out somewhere and I have to fill it back up and blead the slave cylinder for the clutch out and I was told that it was the master cylinder and not the slave. Each time I have to refill it the breaks still work fine just the clutch I have to redo and cant never get more then quarter of pedal out if it. I am kinda thinking maybe my slave clutch cylinder is out.

Thanks for the info

Are you talking about your brakes or clutch losing fluid? Either way you have a leak somwhere, you'll have to find that first and go from there. There's only a slave cylinder for the clutch,not the brakes.
Joe

it has the duel master cylinder which one side is for the breaks and the other side is for the clutch then goes to the slave cylinder for the clutch rod. Iam not finding any leaks on any of the wheels or the slave cylinder for the clutch so I am sure the fluid is going somewhere but not sure. I will go out later today when it cools Off a bit to check it out but its to hot right now.


Thanks

I had this problem on my 60. Turns out the fluid was leaking inside the cab where the master cylinder goes through the firewall.

These are notorious for leaking into the cab. Anyone that has had one for a while can verify that. So, if you have a firewall pad and carpet you may not even notice it leaking into the cab. That stuff will soak up the fluid. You will have to look under the dash and feel around to see if anything is wet. If it has been leaking into the cab then you will also want to pull any padding and carpeting and clean thorougly. Brake fluid will help stuff rust in fine fashion.

you should also be able to smell the brake fluid inside the cab. that is the way that they leak as that is the way that the piston in the cyl faces so it is hard to see
ron

ok, pulled the carpet and what do ya know it was soaked in break fluid. The truck have been sitting for years with a window down and all I smell in there was cat pee lol. I got the master cylinder changed out but now I need to figure out how to bleed the new system and see if I can get that clutch working. The clutch pedal just drops all the way to the floor after it gets about half way down. Anyways, thats for the help so far and I will post any updates as to me getting the system bled correct.

Thanks

There should be a spring at the clutch fork that helps pull it back up, and there's one inside on the pedal as well.

A factory shop manual has really clear pics of the different parts, and it'll show how to bleed and adjust them.

Just plan on replacing the clutch slave too, and probably the line that feeds it as well. My feed line was leaking at the rubber flex union.

-Brad

ok got the clutch bled and it still wont pull the clutch back far enough to let the truck go into gear. The slave cylinder is moving about 2.5 inchs and it still is not enough so I guess my question is now how much does the slave cylinder move when working correct and is there another place I can adjust under the truck?

Thanks

did you adj the slack out of the pedal? you should have about 3/4" of free play at the top of the pedal after proper bleeding and adj
did you stop and consider that the clutch may be poo-poo to
ron
the adj is on the pushrod

Which of the little "grooves" is that arrow-head shaped pivot on the slave's rod engaging the clutch arm? For a V8, it should be in the one closest to the engine block.

You might also need to look at that pivot ball.

Up under the dash there is some adjustment on the clutch rod too. It'll move the plunger farther in the master cylinder.

Also, you might want to take a look at the shifter linkage on the trans. (Unless its a Granny 4spd, which doesn't have any external shifter mechanisms)
-Brad

my clutch only stays about 3 inchs off the floor in which all of it is clutch should it be all the way up?

No matter about the fluid level, that clutch pedal should come all the way back up. You need to check the return springs and see what's going on there and progress from that point.

Spring under the dash looks to be good, it pulls it self up from about half way but from half down it pulls it self down. I am going to get out there today and check the other spring on the slave and look to see what I can start doing some adjustments and also start looking into the idea of a bad clutch. I will try to post some pictures and maybe that will help clear things up.

you could still perhaps have some air in the system. how was the pedal before the leak
ron

all the way on the floor when I got the truck about 1 week ago

It should be all the way up. Check and make sure the rod that goes into the back of the master cylinder is properly adjusted. And realize that the pedal on the LEFT feeds into the plunger on the RIGHT of the master cylinder when you're crawling around under the dash.
There should be two springs under the dash--one for the brake, one for the clutch, to return the pedals to the full upright position. Seems like I had to replace one with a junk yard donor. It was either that, or I had to replace the one at the clutch slave. Either way, there's two springs, and two rods that get adjusted for the clutch.

Sounds like you may need to take the same approach I did--just start replacing everything connected, one at a time, until it's fixed.

-Brad

well I found the adjustment on the rod under the dash and it was out as far as it could go. Not sure where to goto next.

Throw-out bearing, clutch pivot ball inside the bellhousing.

And make sure you looked at the correct rod under the dash... it's the one on the passenger side. I confused it with the brake rod once.

-Brad