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I have recently had the clutch pedal sticking on return about halfway out. This has been happening from cold starts. The clutch appears to be properly engaged but i am not sure and dont want to damage anything. what can i check before forking out cash for new cylinders only to find out its somthing simple like an air lock, some one suggested a collapsed hose? Its a tb45 motor
 

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Interested to hear replies. I'm having the same issue intermittently and not sure why it's happening.
 

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2003 zd30 manual wagon
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I had it happen just once a few weeks ago while out 4wding.
Had been up a really steep hill in 4wd low 1st and at the top it flattened out and i stopped to do a 3 point turn.
As i lifted my foot off the clutch the pedal dissapeared under my foot and the clutch slipped big time.
I put my foot back on it and waited about 20sec and it worked fine again, hasn't done it since.
I too am interested to hear replies
 

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Me too - 99 TD42. I've flushed the system out and changed fluid twice. Very odd. Do your cars have the booster? I thought it might be a vacuum problem.
 

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Must be sunspots. Yesterday while waiting with the engine idling and aircon on, I put my foot on the clutch and it wouldn't return, had to use my toes to lift the pedal, clutch worked as normal, after a few k's all back to normal. May be air or water in brake fluid, the level in the reservoir is higher than normal. Will try a fluid change.
 

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I looked under the bonnet after posting earlier about this and the fluid level in the master cylinder is down. I see a new slave cylinder in my future - be nice if it cures the problem....
 

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I've just put a new slave cylinder in mine but still does it.
 

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Happened to me about 5 years ago and I:
Changed fluid and replaced the slave - temporary fix but it re-occurred.
Ended up replacing the master, and for good measure fitted a braided line to ensure the rubber hose wasn't expanding under extreme heat (fitted a heat shield where the exhaust runs past the slave too). Hasn't happened since.
 

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Old thread but search of this site turned up no answer
What I have found.

The pedal returns only to the engagement point or is sticky from that point is because that is the point where the pressure plate will no longer exert return force on the slave cylinder. The reason for the pedal not returning the rest of the way can be any of the following.
1 - bad return spring or binding pivot point on clutch pedal
2 - missing return spring on the slave cylinder ( some vehicles have one, my '80 Toyota does, not sure about Tundra though )
3 - collapsed rubber flex line ( soft inner wall ) which collapses under vacuum ( portion of fluid drawn to the master cylinder after the pressure plate exerts no more pressure on the slave cylinder ). This line is located between the frame and the bellhousing.
4 - sticky spot in the slave cylinder bore
5 - sticky spot in the master cylinder bore



Diagnostics: Once you have determined that the spring/pivot point is not at fault check the following. Note: the following tests require the cracking of the fittings, bleeding of the clutch system afterwards should be done to ensure no air has entered the system. Do not allow any clutch fluid to remain on painted or plastic surfaces !


1 - Block the wheels of the truck, with the clutch pedal all the way up, crawl under the truck to the slave cylinder and notice the position of the pushrod. Now depress and release the cluch as to make the pedal stick, crawl back under the truck to the slave cylinder and see if it is fully retracted. If it is fully retracted check the flexline for any kind of a soft spot or apparent collapsed area, if there is one, then the flexline is definately bad - replace.

2 - If the slave clyinder is not fully retracked, then try to move move the pushrod back to the fully retracted position, if it moves easy, look for signs of a missing return spring such as a mounting tab on the slave cylinder and release fork where a spring would go. If the slave cylinder pushrod cannot be retracted easily, then carefully crack the bleeder screw on the slave cylinder. Be careful as fluid may squirt out. If fluid squirts out and the slave cylinder retracts completely, then the slave clinder is good, tighten the bleeder and go to step 3. If it doesn't move then the slave cylinder or clutch release bearing/fork are sticking to some degree.

3 - Depress the pedal again and make the pedal stick, place a wad of paper towels under the clutch master cylinder and crack the fitting on the steel line. Be careful as fluid may escape under pressure. If after cracking the fitting the pedal returns to normal, then the flex line is bad ( collapsing internally ). If the pedal has not returned, it points to a sticky master cylinder.

Hopefully the problem is in the pivot point of the pedal or missing return spring on the slave cylinder ( easiest to fix ). Since the clutch pedal feels "normal" while depressing, I would currently rule out any air in the system causing issues. If I had to place a blind bet, I would say you either have a sticky pedal/return spring or a missing return spring on the slave.
 
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