FJ1100 slave cylinder rebuild

[Tom Nolan]

Rebuilt the slave cylinder on my FJ1100 today. I cleaned everything thoroughly.

I have bled the clutch, upwards from the slave to the master. Pushing fluid into the slave with a syringe and a hose. At last the lever felt ok, had resistance. 

But something is wrong. The clutch is not disengaging — the bike pulls though I pull the clutch lever. Also impossible to hit neutral. And I think there is still a leak from the slave cylinder — had just cleaned the floor so it was wet, but I believe there was new spots of clutch fluid beneath the rebuilt and re-fitted slave...

I wonder if I have assembled the piston in the slave cylinder wrong or what the problem could be. I thought I just re-assembled the piston in reverse after cleaning it. Using a rep kit, of course. But maybe not.

Photos of piston attached.


Does it look right? Is everything in the right order?

Also, when I disassembled the slave cylinder, the photographed small seal (laid down to the left of the piston in photo) wasn't to be found anywhere.

The small seal in the photo is a new one which was in my rep kit. I have not figured a way to fit it. Thought it belonged to a variation of my slave cylinder, but not my version exactly, since it wasn't anything like it fitted priorly to the disassembly. Should it be fitted somewhere though?

[Pat Conlon]

Your seal looks like it's going in the right direction. Check the aluminum bore for pitting. This pitting comes from water suspended in the hygroscopic DOT 3/4 brake fluid. Some times a small brake hone will clean it up. If the pitting is too severe, a new slave is needed or sleeving the old slave with a stainless steel sleeve.
The failure to disengage comes from the master cylinder relief port being clogged.
The small seal goes on the push rod. Pull the rod out, clean it, and use a pick to pull the oil seal out of the engine case, clean and press in the new seal, reinsert rod.
Oh yea, don't start your engine with the slave off... if you do, you must report back your results...
Cheers
Pat

[Tom Nolan]

Cheers
Pat

Hey there Pat, thank you! Haha, luckily I have not yet forgot that the slave is off and shot myself in the leg!

Now, how do I unclog the relief port, I guess I shouldn't use any other liquids than the brake fluid in the master cylinder and hose. Or could I as long as I make sure to flush out with lots of brake fluid afterwards?

[Pat Conlon]

Now, how do I unclog the relief port, I guess I shouldn't use any other liquids than the brake fluid in the master cylinder and hose. Or could I as long as I make sure to flush out with lots of brake fluid afterwards?

Open up the master cylinder reservoir and remove the fluid, then the splash shield at the bottom of the reservoir. Often there is a lot gunk collected under this shield. Clean this area out and you will see two openings at the bottom. One is the pressure port and the second small port is the relief port. This relief port gets plugged and thus the line once pressurized can not be relieved when the clutch lever is released. Use only fresh DOT 3/4 fluid to clean out the master.

[krusty]

I'm about to tackle this job today on my 1100 as the kit arrived this morning. Have done it a few times. For cleaning the tiny pressure relief hole in the MC I use a short length, about 4", of a guitar #1 E string. Works on my CB Hondas as well.

[Tom Nolan]

Open up the master cylinder reservoir and remove the fluid, then the splash shield at the bottom of the reservoir. Often there is a lot gunk collected under this shield. Clean this area out and you will see two openings at the bottom. One is the pressure port and the second small port is the relief port. This relief port gets plugged and thus the line once pressurized can not be relieved when the clutch lever is released. Use only fresh DOT 3/4 fluid to clean out the master.

I'm about to tackle this job today on my 1100 as the kit arrived this morning. Have done it a few times. For cleaning the tiny pressure relief hole in the MC I use a short length, about 4", of a guitar #1 E string. Works on my CB Hondas as well.

Went and bought guitar strings. I weren't able to push any of the strings deep down into the relief port, barely noticeable, but I sure did push it in there, and it evidently isn't plugged, as the master cylinder turned into a wonderful fountain without the splash shield.

I've bled and bled the clutch -- pushing the fluid into the slave with a syringe and bleeding it at the master -- but those tiny, tiny air bubbles never ends. I bleed both by pulling the lever just enough for it to make the "click" sound, and pulling its whole range, also combined with tapping the hose all the way from the slave to the master. The clutch is working now, however, ideally the clutch should engage/disengage with the lever farther out than it does at the moment. It's not like youtube and google searches will come up with the trick... Any suggestions on how to get rid of the rest of those tiny air bubbles, fastest or easiest way possible?

[T Legg]

I tie my clutch lever back then let the vibrations of the engine idling for 5 to 10 minutes work the bubbles up.

[Pat Conlon]

I tie my clutch lever back then let the vibrations of the engine idling for 5 to 10 minutes work the bubbles up.

Hope you have a couple box fans cooling the engine....

[FFGO]

I just went through a few days of clutch bleeding. In the end I found the last bit of air was trapped in the banjo bolt/fitting at the master cylinder.

[gumby302ho]

 I also went through this and the best thing to do is tape\tie the clutch lever to the bar and walk away and enjoy your favorite beverage then dinner then sleep and try it all again the next day, it works.