After all this work I've done on my 91 4X4 I'm having trouble with simply bleeding a new clutch master Cylinder. It obviously worked when I pulled the rig into the yard. I've looked around elsewhere, I've seen some pretty weird stuff(the cutting a bolt lengthwise with a hacksaw and inserting a wedge to increase bolt size really threw me) Anyway I did a slave about 25 years ago no big deal, I follow the haynes manual, nothing allows me to "pump about 10=20 times until pressure is felt and then yada yada yada..I adjusted the throw to match the old one. No matter what I do it won't pump up, I can't find any leaks..Do you have to "prime" a new master cylinder? I checked the flare it looks fine. The pic shows some kind of film or skin on the outside of the line(looks like some kind of original protective skin(packaging) the white stuff in the pic next to the fitting
Any suggestions, this is just pissing me off as each time I open the fitting I spill a reservoir's worth of fluid..
Thanks

 

I have had bad parts out of the box from part stores. Is your slave cylinder trying to build up pressure? It could be the culprit now.

Try bench bleeding the Master Cylinder with it off of the truck. If you can hold the pressure back with the force of your finger, it is bad. If working right, with just about all the strength you can muster it should blow fluid past your finger.

Also I swap out the master and slave cylinders out as a pair anymore. Seems like when I changed one of the two in the past, the other one will fail at a later time. My guess is the increased pressure just eventually takes it toll on the other one.

 

From the amount of time and searching I've done on this site I can tell you that there are many out of the box failures from all of the parts stores, especially AutoZone. There are also many stories of early failures from the same stores. The only parts store replacement I've read of that seems to be decent is from NAPA.


Personally I wouldn't do that either when you could get the original Aisin parts for about the same price if you do a little online hunting.


Unlike the normal parts store replacements the Aisin stuff seems to work right out of the box and last a very long time.

 

It seems since the rubber line is not attached to the slave cylinder it almost never gets changed.!!!!

Just like any hydraulic lines they do tend to balloon under pressure.

I have had good luck with the Aisin hydraulics after dealing with junk till I learned.

I keep extras on the shelf.

 

On all advice Thanks, too bad I bought the clutch job from AZ, so far NAPA on everything else, AZ claims lifetime warranty, even took my info for it. NAPA $34 for master and $18 for slave. AZ was $23 for master and $12 for slave. So I saved a few bucks, might not have been worth it. I cranked on the master line so hard I thought I'd strip it out. So per the advice here new master and slave, original Toyota line from junkyard looks untouched since install $8(a hassle pulling it out without damage), I already replaced the rubber flex due to a goober(not long enough to accommodate the 3 inch BL, used a front brake line new that belongs stock in this vehicle, a perfect fit with perfect slack.. I don't believe in spooks and magic so a complete replacement should solve it.
Sad to say it's probably going to turn out the original MC was perfectly fine, just a bad set of troubleshooting skills applied in this case, and a rush to get it up and running
Thanks all...

 

what you are saying is that the plunger on the slave cylinder does not move when you push the clutch in? it'll take two people to make that test happen.

did you try cracking the valve at the slave cylinder and letting fluid drain from there, without pumping? keep refilling it at the reservoir, before it gets near the bottom?

 

Ive changed a ton of brake a clutch stuff at work, and I always use a vacuum bleeder to suck the fluid down to the new part. Takes a the hassle out of it and saves a ton of time

 

A friend of mine and me was talking just the other day and feel NAPAs quality has gone down hill lately. I find Aisian parts online for less then the part stores sell them. One of my brothers Ford fuel pump went out on him. I found a factory replacement for $21 and the stores were $100 plus for it. There is not a single source for them online, just have to check several different sites. You can get great parts for a better price, only draw back is if you need the part today. Glad to hear you got it up and running.

 

Personally I think it started a few years ago. Quality replacement parts are getting harder to come by every year thanks to all of these companies trying to build their bottom line. It seems the new normal is to sacrifice quality and dependability for that all mighty dollar.

 

My local Napa used to have a few independent Auto Parts stores in the Area

Now they have a Advanced Auto and Auto Zone within a 1/4 mile.

Truth be told in most businesses very few are willing to pay the price for higher quality products.

Only in the last few years has Napa really tried to attract the walk in customers. At least in this area .

 

I don't really care for the other parts stores in my town, it's like choking my pride down or something. When I go to CarQuest or NAPA the lot is clean and for the most part the cars parked there are stock, muscle cars, or 4X4's in decent condition. When I go inside the place has mostly shoppers of middle age and older older guys along with farmer type dudes.

When I go to Oreilley's and AutoZone the parking lot is stained with oil leaks and the cars are mostly dirty beat to crap cars and imports with fart can mufflers and their fancy but highly needed wings. The shoppers inside are mostly young to middle aged. Could be different in your area...
(Ok that's not 100% but damn close)

I do still go there but most of the time I end up leaving empty handed.