Sue Burch

ok so my truck is an 04 but was told to come here so here is the issue....ok so to begin with this ran fine prior to replacing a slow leaking rear main seal... so my husband who isnt a newbie to mechanics... been doing this for years as his own mechanic so he knows his stuff... but this is stumping him... note this was fine prior to... so he replaced the seal and got everything back together went to bleed system as he had to put new tranny oil in... mercron i believe was what was recommended ... gears would not engage with motor running... but when off gears were smooth as silk... yea i know i was the usual assistant lol.... but when truck runs refuses to go into gear.... so was recommended to pump clutch 15 times and leave sit then repeat... then try Shifting again... clutch was fine... so he got it to shift but still very hard to get into gear while running... been taking it to work... now his pedal is hard as a rock wont go anywhere and blew line to slave... new slave too BTW... anyone have an answer?? As i have stated before we have been driving it all this time and no issues with shifting.... After breaking down out of town and having a mechanic redo slave.. it blew the line and spring and line... the master was replaced and so was the line thus a whole new system was done... and still the same issue... so here i found this....The clutch master cylinder is not relieving the pressure when applied. I recommend bleeding the clutch master cylinder and retest. If the condition continues, then replace the clutch master cylinder. If you need further assistance with your hose blowing off the slave cylinder, then seek out a professional, such as one from Your Mechanic, to help you....
ok so we are at a mechanic and NO ONE has seen this happen before..not any garages we are close to or anything. so does this mean we have to get new line and master too??? THIS BLEW THE LINE IN SLAVE NOT LINE GOING TO SLAVE

white89gt

These and the Ranger have to be bench bled. They are very difficult to get the air out of by installing the parts dry. This is on the Ranger/Explorer, but it is the same principle.

BTW, I am uncertain as to what he used in the system.... but it needs to be DOT3 Brake fluid - Not ATF!

NFortin1966

Yes, The hydraulic clutch does use DOT3 fluid, also this system is quite different than the hydraulic system used for the brakes. On this system, you DO NOT fill the reservoir all the way to the top line as the level of fluid RISES as the clutch wears down, unlike on the brake system were the fluid lowers as the pads wear, so if the reservoir is topped off, it is overfilled and will act as if the clutch is not working. Now mercon is a compressible fluid, and if DOT3 has never been used in the new system, you should be ok with it, as the two do not mix. If you wish to use DOT3, the entire system must be flushed completely.

Mercon is called for inside the transmission to lubricate the gears,

Sue Burch

ok guys here is the new issue well not new but the root of the causing issue.... and now have it at a mechanic so please dont tell me to take it to a garage its there... so got it up on lift and replace the whole system... new master... new line and new slave.... bled system,.bled master.. gravity bled all components and yes the video that white 89 posted is basically what we did so thats should be sorted ... Ha ha funny nope still blowing line to slave ... spoke to 3 other mechanics who know their stuff and some have been at this 40 some years and no one has seen nor heard of this issue... so assumed one of the new parts were faulty.. can happen not all of them but which one do you rule out bad master hmm maybe.. bad valve at end of line ?? perhaps bad connection on slave?? hmmm doubtful... but anyhow all under warranty so all were replaced second time.... sooo start all over again dropped tranny installed new slave new line and master... gravity bled whole system and no air out of slave and then bled master and yes tapped the whole system to assure air bubbles were out..... still blowing line going to the slave soooo ordering new line for the third time assuming that valve is bad and not allowing the fluids to return.. had to be ordered... more than likely a bad valve at the end... ok so thats ordered...still dont get why its blowing the line tho three times to get us here to the third line in which we are waiting for ... none of us understand why the line is blowing tho and last time parts came form line a spring and plastic piece... that was second round

River1

I probably should just let this stand but. . .

A non-vacuum, power assisted hydraulic brake system works the same as a clutch. The compressibility of a liquid is the inverse of the liquids bulk modulus. (Bulk modulus is the total of resistance to compressibility from all directions (3D) opposed to limiting calculations to lateral, vertical, etc, forces.) To get any significant amount of compressibility in a hydraulic system a liquid along the lines of mercury would be required. The problem with using Mercon is the seals. You'd need to change all the seals to ones that are made to be used with Mercon. Plenty about the effect of using Mercon with the wrong seals on the internet.

River1

What happens with the slave when its free of the clutch and transmission? If it doesn't activate that's your problem. If it does activate you've got some kind of mechanical problem. Slave cylinders are finicky. For example, you have to have the right cylinder to match the thickness of your flywheel and the available space. I use this example to highlight that although you may have a mechanical problem it may show up because of a bad or wrong slave. Fitment is a mechanical issue. The slave may be trying to work as intended but it doesn't have the required space to work the clutch. Or, there is too much space and nothing is stopping it. This can get in to the workings or operation of different slaves. Not all have limits to their operating range. In this example everything may work fine, just not together. I sure as heck wouldn't rely on a number on a box from Autozone or similar place to be confident about a part.

River1

Probably should ask if the bearing was set up with the proper bearing gap to the fingers to begin with? If not, than that's probably your problem. It's not a part to be just put on.