So i just rebuilt my carbs over the winter and put everything back together. I went to take her out for a test run and found out i have no clutch. I pull the lever and nothing is happening, so after cruising this AWESOME repository of knowledge, i decided that it was probably my clutch slave cylinder. I ordered a rebuild kit from RPM ( thanks for the 1 1/2 day turnaround!!!) and popped it off and swapped out the seals and spring. I bled the system, and bled the system, and bled the system... Nothing. The clutch never seems to develop any pressure in the system, the lever is still limp. So now i am wondering if anyone has any input on whether i should rebuild my clutch master cylinder? Its worth noting that when i went to drain the system before i pulled the slave off, i could not get the master drained by pumping the clutch lever. I had to soak it out with some paper towels. I was just wondering if that proved that my master cylinder is not pumping as it should? I appreciate any input you guys might have.
Josh
I'm no pro at this, but, assuming you rebuilt and CLEANED the slave properly, [edit: and BLED it properly as pointed out below...]
1. Not being able to develop pressure at the master would mean the master needs work, so yeah, that symptom lines up.
2. There's not much else in the system, so it's probably the master just by process of elimination.
No chance you tried to start the bike while the clutch slave was off, is there? Just checking, I don't know what symptoms develop when that part is absent, but you probably would have mentioned if a spear shot out of your bike.
A questions on you bleeding procedure: did you have the outlet tube rising from the bleeder and did it have any fluid in the tube? If not it will suck air back in on the return stroke. Also you may want to try injecting fluid in through the bleeder hole to push the air to the master; a large syringe works. I also used a small pump that is used for putting gear oil into the lower unit of an outboard motor.
Be sure the cover is on loosely or you will have fluid everywhere. In my experience so far...if the master is bad it will leak a bit.
I always just tighten the bleeder before I release the lever, so the return stroke can't pull anything back in... Or am I misinterpreting what you said? I thought that was just how it was done, I can't imagine how it could suck anything back in this way except for the piston.
If you elevate the tube above the master and it has a bit of fluid in it, it cannot suck air...you would not need to tighten/loosen each pump. Usually enough fluid will enter the tube on the first stroke; I always try to have some in the tube to start.
Thanks for the quick replies!!! I believe i did reassemble the slave correctly ( with a little help from Mr. Clymer), and i was also sure not to start the bike with the slave off. LOL i have seen the comical posts about this on here in the past. I had my Dad help me with the bleeding process, we were sure to close the bleeder screw each time before i released the lever to avoid sucking anything back in. I was never able to get enough fluid to come out of the bleeder to fill the tube, just small amounts. Looks like i need to hit Randy up at RPM again and order the master rebuild kit. Thanks again!!! One more thing, have any of you rebuilt the slave with one of RPM's kits? It had one more plastic oring in it than what came off the bike. It was smaller than the others and made of a harder compound (not rubber), im just not sure what this is. Does this kit do multiple bikes?
Josh
Hi Because you noted it was so difficult to bleed, you may want to try the two techniques I mentioned...I have found that these systems are much more difficult to bleed than a car. Even a very small amount of air will give you "no-clutch".
I will give the bleed another try. I did notice some moisture under the master before i started all this. It was such a small amount that i just shrugged it off though, seems more important now... It never dripped it was just a little wet by the piston, im leaning towards the master being bad. Thanks everyone for the advice.
Quote from: akadaryl33 on June 17, 2013, 03:52:26 PM
One more thing, have any of you rebuilt the slave with one of RPM's kits? It had one more plastic oring in it than what came off the bike. It was smaller than the others and made of a harder compound (not rubber), im just not sure what this is. Does this kit do multiple bikes?
Josh
Josh,
The kit is Yamaha specific. There should have been five (5) parts in the kit. The slave seal, dust boot & spring. The bleeder screw cover and the clutch pushrod seal for the block.
Take a look at the photo on my website and let me know which part you are inquiring about.
Randy - RPM
The small seal is for the clutch push rod
Josh,
I would guess the master is fine. I had a similar problem I used a vacuum pump to suck the fluid into the system.
I tried pumping the lever for a while before I gave up. Like you I thought the master was bad, but once I got fluid in the system it worked fine.
I also did the zip tie trick on the lever over night that helped some too, despite my skepticism.
Thanks for the info on the pushrod seal Randy. Is it possible that the old one completely disintegrated? I did not remove one from it when disassembling.... Now I feel really stupid lol i would assume that my problems begin and end with the extra part sitting on the work bench.
Quote from: akadaryl33 on June 17, 2013, 07:10:53 PM
Thanks for the info on the pushrod seal Randy. Is it possible that the old one completely disintegrated? I did not remove one from it when disassembling.... Now I feel really stupid lol i would assume that my problems begin and end with the extra part sitting on the work bench.
No, that seal is separate from the slave cylinder, it is the seal in the block at the pushrod.
Randy - RPM
I've known more than a couple of people who have installed the slave piston seal backwards, then wondered why it wouldn't bleed.
I did it myself once, but caught it before putting things together. :i_am_so_happy:
Well i am feeling more than a little foolish about the pushrod seal. I will pull it all apart tomorrow and try again with the proper parts installed, and give it a go again. I found the pushrod seal in my Clymer under the clutch section. There was no mention of it in the slave cylinder section. Randy if you happen to see this, would the lack of a new pushrod seal possibly cause the problems i am experiencing. FWIW i procured a vacuum bleeder to use tomorrow too.
Nope, that seal is only there the seal oil in the engine.
You have a bleeding issue.
Randy - RPM
Well, the clutch master could be worn, or the seals in it torn, but its still more likely that you just have air in your system. The FJ clutch is 'difficult' to bleed.
As has been mentioned on this list before (many times), "reverse" bleeding works much better than trying to force fluid and air down to the slave.
Just wrap your slave bleeder threads with teflon tape so you don't leak there and fill the clutch system from the slave up to the master. Use a large hypodermic syringe (50cc or larger) like you can get at farm supply stores. After you have pushed enough fluid UP to at least half fill the reservoir, put the gasket and lid on, and tie the lever to the bar overnight.
You should have a working clutch in the morning.
Arnie
Bleeding at the master cylinder banjo bolt ,may also help
Well thanks to everyone for their help!!!! I got all the parts in the right place and used the vacuum bleeder to fill the system and voila! I have clutch!! I think I may still need to bleed one more time because the clutch bites further out than it did before. In any event this is the first time in 2 years it has been all back together and running well. Can't wait to get out for a long ride!!
Quote from: akadaryl33 on June 18, 2013, 07:58:12 PM
Well thanks to everyone for their help!!!! I got all the parts in the right place and used the vacuum bleeder to fill the system and voila! I have clutch!! I think I may still need to bleed one more time because the clutch bites further out than it did before. In any event this is the first time in 2 years it has been all back together and running well. Can't wait to get out for a long ride!!
To get the last remaining air out of the system, cable tie or tape the clutch lever back to the handle bar overnight. The next day you will have your clutch feeling as good as new. Pete. :i_am_so_happy:
Will do... Thanks!
Quote from: akadaryl33 on June 18, 2013, 07:58:12 PM
I think I may still need to bleed one more time because the clutch bites further out than it did before.
Sounds like it is taking up where it should. The clutch is not meant to bite right off the grip. Somewhere near 3/4 out is normal.
I have had a shitty clutch, and it might grab at as low as needing to pull all the way to the grip, and still not entirely engaged. I doubt he'd mention it is not engaging where it did before if it was 3/4?
About to rebuild my clutch soon, so this has all been illuminating.
Slightly off topic, but related enough to make me ask: my rear brake had a locked piston since I got it that slowly got more and more stuck. I went ahead and rebuilt the caliper, flushed the lines, bled thoroughly. When I depress the rear pedal, it goes all the way down--if the wheel is on the center stand, it will grab, but when riding there's not enough force to even really feel it.
I've been assuming rear master, just as this guy did for his clutch, so to speak. Any reason I should diagnose it otherwise?
fintip,
Try bleeding it again....sounds like it needs it.
Jeff
Your brake pads don't have fluid or grease on them kyle :scratch_one-s_head:
Rod
Trust me, I bled the hell out of it, and had another guy who has bled hundreds of brakes in the shop come over and try as well. It just wasn't working. There's really not that much line between the rear master and the rear caliper, it isn't that much to bleed.
I figure it has to be something in the caliper (did I forget something?), or the rear master cylinder. The fact that the previous owner mentioned briefly when I bought the bike that he had rebuild the rear master cylinder (when I was asking about the clutch slave cylinder, to which he had done nothing) and that the bike came with a funky rear brake that only got worse over time (the bike also sat for [at least] a year before I got it) makes me think I should definitely get into the rear master cylinder.
No?