Driving in 34 F weather about 7 miles to my storage my 40 started slipping clutch...RPM went from about 2000 to 3000 as clutch was slipping about every 5-10 seconds,but was still ok...As I was ready to leave my storage I could"t move....Clutch was so hard to push and than too easy to push...Brake fluid from clutch master disappeared so I put a new fluid and it slowly disappeared too...I checked the slave cylinder and squeezed a little rubber hose (Part of rubber dust boot)and fluid was pouring out...Slave cylinder has about 3000 miles on it and is almost new(aftermarket)..Master is older,but looks ok....What is the problem ???Slave cylinder or master cylinder???Thanks for your opinions...
I broke down today-clutch problem... (1 Viewer)
- Thread starter drnekFJ40
- Start date
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Mike,
It sounds like your slave is failing and dumping all your fluid and allowing air in your lines.
The experts always recommend replacing the slave and master at the same time.
It sounds like your slave is failing and dumping all your fluid and allowing air in your lines.
The experts always recommend replacing the slave and master at the same time.
- Thread starter
- #3
Thanks,Danny....About time to order new slave cyl.....I wanted to do it year ago just to have a spare one but didn"t...What the heck the aftermarket one only lasted 2,5 years and 3000 miles???I will get AISIN THIS TIME ....
John McVicker
SILVER Star
As Danny suggested...if you can spare the $$ I'd replace the master clyinder at the same time...otherwise, 'pay me now or pay me later'
brian
SILVER Star
other issues as well though.
a bad master and/or slave will not cause a clutch to slip.
a bad master and/or slave will not cause a clutch to slip.
That's what I was just thinkin.
There is no reason to replace both the master and the slave at the same time. Best to just figure out which part is actually bad and either repair or replace it. Hydraulic systems are extremely simple to diagnose. People who get a failure of one part after replacing the other are simply reacting to what probably is a long-term contamination of their system with moisture and rust pitting. Switching from DOT3 or DOT4 to DOT5 silicone fluid may eliminate the need for replacement for many trouble-free years. Silicone is not hygroscopic like DOT3 and 4, so water and rust will no longer be a problem. Just be sure you take the old hydraulic system apart and clean out all the old fluid and crud before filling with the silicone. If you make the change to DOT5 silicone and eventually have another system failure, all you need to do is replace the rubber cups because the cylinders themselves will be undamaged. By the way, a few years ago I published a quick fix on this site for a leaking clutch slave using the piston/cup from a common Toyota pickup that you can get for $15 at Advance Auto and be back on the road in minutes. Pretty sure I included the part number as well. My son's 40 is still using it after 6 years.
By the way, if the OP repeatedly pumped the clutch trying to get it working, he might have overwhelmed the slave and kept it from retracting, causing the clutch to slip. That will bleed off quickly and the clutch should re-engage the next time he tries it.
By the way, if the OP repeatedly pumped the clutch trying to get it working, he might have overwhelmed the slave and kept it from retracting, causing the clutch to slip. That will bleed off quickly and the clutch should re-engage the next time he tries it.
Sounds like your going to have time to work out the slave/master issue while you are replacing that clutch and pressure plate. The hydraulics will keep your clutch from releasing but unless your clutch is stuck depressed, it cant make it slip. A pressure plate failing or a worn out clutch disk will though.
- Thread starter
- #10
I was just thinking last night what might cause my clutch slipping during my 7 miles drive....Maybe after that drive hydraulic system got overheated and busted the slave release cylinder....Or as you mentioned-my clutch friction plate or pressure plate is worn out....
- Thread starter
- #11
Yeah,you might be right....If I go back and think about few thinks I was not sure about my clutch like for example-After cranking up I put my 40 in reverse to drive out of the shed and slowly releasing clutch,motor started to die unless I put too much gas ...I have to repeat -push clutch back ,release,step on the gas a lot..It looked like power is missing somewhere..After few times it finally left my shed...I thought it is just that motor is not warmed up yet...After warming up was ok...Not a problems with shifting or nothing else...When I bought 40 almost 3 years ago-clutch supposed to be new and I drove maybe 5-6 000 miles?
The principal to replacing both is that a 15 year old slave will have a similar amount of wear and the same number of cycles that a 15 year old master has.
If they're a year old... and one failed I'd proceed differently.
I recently rebuilt my Master a second time and replaced the slave when the system was falling. It was well past the recommended best before date of 10 years.
MOTOV8R
SILVER Star
What is the status of your clutch fork return spring? Is there any binding between the slave and the fork? Have you inspected the clutch, does it have any fluid on it?
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- Thread starter
- #14
return spring looks quite new and OK...pushrod on the slave release cyl. is pushed all the way out and rubber dust boot stretched...That is the problem I think...As you guys said before...
brian
SILVER Star
yes the bottom of the bell housing should have a tin cover that can be removed.
you'll be able to see the edge of the friction disc pinched between the fly wheel and pressure plate.
you'll be able to see the edge of the friction disc pinched between the fly wheel and pressure plate.
MOTOV8R
SILVER Star
If you can take some pictures of the slave cylinder and the clutch with the cover off that could help.
- Thread starter
- #18
I wish I got a smart phone to take a photo,but I don"t...Rod on the slave is sticking out too much and that is the problem....It is cold to work on my 40 now but I will check later...Slave release cyl needs to come out and I will put a new one in and see what it does...New Aisin are not that expensive-about 28,-$ ...
