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TR2/3/3A Clutch Swallows Air -- TR3
- Thread starter Moseso
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OP
Moseso
Jedi Knight
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I am confident of the master -- and its adjustment -- and, further, don't know how it could make bubbles in the slave cylinder without filling the feed tube first.
Collapsed line? That would make some sense, too, except my line is also < four-years-old.
I suppose I should replace it (cheap enough) when I rebuild my slave. I'm really swinging in the dark at "why." I am certain of the symptoms but have no idea why. Fortunately, these are all cheap-&-easy repair projects. But, dang it, I want to know WHY!
Also -- Fortunately, I am adept at driving with no clutch disengagement mechanism. There is talk of this in another current thread. I've driven my '65 Volksy bus for days with no clutch (broken cable). Also my '65 BMW cycle (ditto) (also, easier). Why don't they sell these oft-needed parts at the corner 7-Eleven? That's how I got home, last Saturday night. Speed-shifting, and watching way ahead for the signals.
Collapsed line? That would make some sense, too, except my line is also < four-years-old.
I suppose I should replace it (cheap enough) when I rebuild my slave. I'm really swinging in the dark at "why." I am certain of the symptoms but have no idea why. Fortunately, these are all cheap-&-easy repair projects. But, dang it, I want to know WHY!
Also -- Fortunately, I am adept at driving with no clutch disengagement mechanism. There is talk of this in another current thread. I've driven my '65 Volksy bus for days with no clutch (broken cable). Also my '65 BMW cycle (ditto) (also, easier). Why don't they sell these oft-needed parts at the corner 7-Eleven? That's how I got home, last Saturday night. Speed-shifting, and watching way ahead for the signals.
OP
Moseso
Jedi Knight
Offline
STILL sucking air...
Did the slave cylinder, Saturday. Readjusted the pedal free-play on the master. The foot valve is demonstrably opening and closing. Becky pressed the clutch while I watched in the reservoir. There is a little spurt of fluid into the reservoir, just before the foot valve closes at the beginning of the stroke. Also, if the foot valve didn't open, I wouldn't be able to bleed the system -- no fluid could get into the master.
The problem has worsened. I can't get two days out of my clutch without it becoming totally inoperative.
The collapsed hose theory doesn't have much appeal to me, as I can see and feel the clutch returning smartly. There is no restriction in the clutch travel, either way. It's the only thing I haven't touched yet, so I'll probably replace it -- but I have lost all faith that I can repair this.
Reservoir cap vent: OPEN <span style="font-style: italic">check</span>
Master cyl: Rebuilt 2011, foot valve demonstrably doing it's job. Exterior dry as a BONE. <span style="font-style: italic">check</span>
Slave Cyl: Rebuilt last week. Interior shiny. Exterior dry as a BONE. (Oh, alright, it had a film of motor oil on it, but I don't lose fluid) <span style="font-style: italic">check</span>
Hose: untouched, but isn't restricting clutch movement in any discernible way. No <span style="font-style: italic">check</span> yet.
WTF else????
Starting to feel like composing a Craigslist ad. "Cool TR3 -- Needs a little work."
OR -- and this is a better idea -- convert the car to cable operated clutch! I'll bet I could cobble something together.
Did the slave cylinder, Saturday. Readjusted the pedal free-play on the master. The foot valve is demonstrably opening and closing. Becky pressed the clutch while I watched in the reservoir. There is a little spurt of fluid into the reservoir, just before the foot valve closes at the beginning of the stroke. Also, if the foot valve didn't open, I wouldn't be able to bleed the system -- no fluid could get into the master.
The problem has worsened. I can't get two days out of my clutch without it becoming totally inoperative.
The collapsed hose theory doesn't have much appeal to me, as I can see and feel the clutch returning smartly. There is no restriction in the clutch travel, either way. It's the only thing I haven't touched yet, so I'll probably replace it -- but I have lost all faith that I can repair this.
Reservoir cap vent: OPEN <span style="font-style: italic">check</span>
Master cyl: Rebuilt 2011, foot valve demonstrably doing it's job. Exterior dry as a BONE. <span style="font-style: italic">check</span>
Slave Cyl: Rebuilt last week. Interior shiny. Exterior dry as a BONE. (Oh, alright, it had a film of motor oil on it, but I don't lose fluid) <span style="font-style: italic">check</span>
Hose: untouched, but isn't restricting clutch movement in any discernible way. No <span style="font-style: italic">check</span> yet.
WTF else????
Starting to feel like composing a Craigslist ad. "Cool TR3 -- Needs a little work."
OR -- and this is a better idea -- convert the car to cable operated clutch! I'll bet I could cobble something together.
TexasKnucklehead
Jedi Knight
Offline
I'd scratch the craigs list and cobbling ideas before you start regretting it.
There is a clevis adjustment on the rod at the slave and one on the master. Is it possible you are over stroking the M/C? When the pedal is the whole way in, the piston (and seal) could be forced against the bottom of the M/C. Maybe it has nothing to do with your issue, but it's worth a look.
There is a clevis adjustment on the rod at the slave and one on the master. Is it possible you are over stroking the M/C? When the pedal is the whole way in, the piston (and seal) could be forced against the bottom of the M/C. Maybe it has nothing to do with your issue, but it's worth a look.
Geo Hahn
Yoda
Offline
Have you rebuilt the master cylinder? If a slave fails it will leak but most M/C failures I have had presented no leak, just marginal or ineffective performance.
What has failed on those has been the little seal at the end of internal bits. This one:
I think it works like a check valve and when it fails some fluid gets past it and back to the reservoir.
What has failed on those has been the little seal at the end of internal bits. This one:
I think it works like a check valve and when it fails some fluid gets past it and back to the reservoir.
OP
Moseso
Jedi Knight
Offline
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I think it works like a check valve and when it fails some fluid gets past it and back to the reservoir.[/QUOTE]
Exactly right. And then you get no (or reduced) pressure down the line to the slave. Sadly, not my problem. My problem is air getting into the system from somewhere. When freshly bled, and not full of bubbles, The clutch operates just as it should. Then it gulps down some more air -- and doesn't operate at all like it should.
And, yes, the master cyl. was the first thing I rebuilt -- just last summer. I've got another kit on the way.
(Knock wood, knock wood, knock wood -- I can't even believe I'm saying this out loud) I'm sure glad it's the clutch doing this, and not the brakes!
Exactly right. And then you get no (or reduced) pressure down the line to the slave. Sadly, not my problem. My problem is air getting into the system from somewhere. When freshly bled, and not full of bubbles, The clutch operates just as it should. Then it gulps down some more air -- and doesn't operate at all like it should.
And, yes, the master cyl. was the first thing I rebuilt -- just last summer. I've got another kit on the way.
(Knock wood, knock wood, knock wood -- I can't even believe I'm saying this out loud) I'm sure glad it's the clutch doing this, and not the brakes!
OP
Moseso
Jedi Knight
Offline
Re: Clutch Swallows Air -- TR3 [Solved???]
About three-or-four weeks ago, I bled the clutch, got in the car -- and didn't even make it 1/4-mile before losing my clutch pedal. So I put the car in the garage and waited -- first, for parts and, second, for time to work on it.
Yesterday, I got around to it. First, I replaced the cover gasket on my leaky rear axle. I think I got it this time...
Then I drained the clutch hydraulics. I looked at the hose to see if it had the problem that Randall describes. Nope. It looks brand-new -- which it pretty much is. So, with nothing else left to work on, I threw a new seal kit into the master cylinder. Nothing looked amiss inside there -- good looking seals, shiny bore -- but, what the heck, a seal kit is cheap enough, and it's just not that hard a job to do.
Becky wasn't around to help me bleed the system, so I thought I'd try to "gravity bleed" it, as I've read about here. Boy, howdy! Does that ever work slick! I just put some fluid in the reservoir, crawled underneath and opened the bleed valve, and, after about a minute, there was fluid running out of it. I closed it up, thinking, "If I actually have a clutch, I'll be a monkey's uncle." When I climbed in and pressed the pedal, it felt fine-and-firm. Ook, ook!
So far: yesterday's test drive and this morning's ride to work, the clutch works just fine. It worked fine like that for a year, after the last time I rebuilt the master -- and then began sucking air again.
I STILL have no idea how this failure occurs, but I think I have proven that, if you just tear the whole system apart and rebuild EVERYTHING, you have to at least be touching the cause.
About three-or-four weeks ago, I bled the clutch, got in the car -- and didn't even make it 1/4-mile before losing my clutch pedal. So I put the car in the garage and waited -- first, for parts and, second, for time to work on it.
Yesterday, I got around to it. First, I replaced the cover gasket on my leaky rear axle. I think I got it this time...
Then I drained the clutch hydraulics. I looked at the hose to see if it had the problem that Randall describes. Nope. It looks brand-new -- which it pretty much is. So, with nothing else left to work on, I threw a new seal kit into the master cylinder. Nothing looked amiss inside there -- good looking seals, shiny bore -- but, what the heck, a seal kit is cheap enough, and it's just not that hard a job to do.
Becky wasn't around to help me bleed the system, so I thought I'd try to "gravity bleed" it, as I've read about here. Boy, howdy! Does that ever work slick! I just put some fluid in the reservoir, crawled underneath and opened the bleed valve, and, after about a minute, there was fluid running out of it. I closed it up, thinking, "If I actually have a clutch, I'll be a monkey's uncle." When I climbed in and pressed the pedal, it felt fine-and-firm. Ook, ook!
So far: yesterday's test drive and this morning's ride to work, the clutch works just fine. It worked fine like that for a year, after the last time I rebuilt the master -- and then began sucking air again.
I STILL have no idea how this failure occurs, but I think I have proven that, if you just tear the whole system apart and rebuild EVERYTHING, you have to at least be touching the cause.
