Clutch fluid leak

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Rich, I've done it both ways, with the oil filter off, and with it in place. Remove the single bolt that holds the rubber overflow lines and move the bracket out of the way, then remove the single bolt holding the shifter linkage to the shaft and move the entire assembly out of the way, then you have clear (but tight) access. If this is the first time your doing it, it way be easier for you to remove the oil filter just so you have a better view. Remove the lower black cowlings on both sides. A small mechanics mirror and light are helpful in seeing that everything is clean in there. Also make note of the direction of the banjo fittings. That's about it. Good luck.
Hi All: I am doing this job on my 2007 tomorrow (Sat. Feb. 18) with the help of a friend who is more agile than me.

I have done all the prep work outlined by Igofar above and would only add that you should mark the position of the shifter mechanism on the tranny shift (I used a little spot of typewriter correction fluid) BEFORE you remove it. I certanly plan on doing an article and have been keeping notes on everything I did all prior to hurting my back.

Cheers and and wish us luck.

Pete
 
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What are the parts you are using for this and where do you guys go for parts? From what I can see it seems to be a rebuild kit (gaskets and a spring) and also also separate paper gasket, does that sound right?
 
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Hi Rich:

[FONT=&amp]Today was a beautiful 21C (nearly 70 deg. F) and it was also a very big day in the Disaster Central Workshop. A friend and I replaced the clutch slave cylinder (CSC) on my 2007 ST1300. The big problem is access and how the heck to get tools on the CSC and the hydraulic fitting that is attached to it - and which tools will fit and work in that tight space. This is because the danged thing is mounted up on the backside of the engine case and is crowded with the oil filter, the gear shift linkage, a bunch of hoses and the front edge of the swing arm - and there isn't an easy way to even see what you're doing - let alone do it.

The photo below shows an ST1300 rear engine case - and the greenish area in the lower centre of the case with three bolt holes is where the CSC goes. The hole with the big bearing on the upper right is where the drive shaft attaches and below it is the hole for the gear shifter shaft. The large silvery hole on the lower left is where the oil filter mounts. You can easily see that the clutch slave cylinder mounting is pretty tangled up with everything else.

[/FONT]
ST1300_rear-engine-cover.jpg[FONT=&amp]

The next photo shows a clutch slave cylinder and the engine case - with the oil filter in place.

[/FONT]
Clutch_Slave_Cylinder_02.jpg[FONT=&amp]

All of the parts you will need for the job are listed in the text below. I ordered them through my local Honda dealer and they were in stock and delivered to me within a few days. The total cost of the parts was around $95 CDN (the CSC was $75.81, the gasket was $5.22 and the crush washers were $4.49 each - you need three of them). Given the modest cost of the new clutch slave cylinder and the challenging nature of the job - I didn't even think of trying for a rebuild on this one. It is just too difficult getting in there and getting the cylinder installed.

Despite all of that, the job took about an hour and here are the salient points:

PRELIMINARIES
I would take the bike to a car wash and spend a little time hosing the crud off the underside of the engine and especially the area at the front end of the swing arm and the rear end of the engine;
Assemble all of the tools and other stuff shown in the photo below. Here is a list:
  • a garbage bag to drape the fuel tank and fairing to protect them from brake fluid spills;
  • a good bright shop light to illuminate the dark corners of the underside of the bike;
  • an Allen key of the (5 mm as I recall) to remove your fairing belly panels;
  • a strap wrench to remove the oil filter (plus a little drain pan for the oil you will loose);
  • flex ring ratchet wrenches - 8, 10 and 12 mm. You want really good ones with ratchets that have a lot of pawls in them so that they will work even if only moved through a few degrees of rotation.
  • an 1/4" drive ratchet (also with fine rotation pawls) with a fairly long handle and an 8 mm hex socket to match;
  • a blade tool of some type to scrape off the old gasket from between the CSC and the engine case (we also used a little brass brush);
  • a little jar of Vaseline petroleum jelly (the stuff you use on baby's bums);
  • a tube of high-temp silicone grease - for the socket in the CSC that engages the clutch push-rod;
  • a good JIS screwdriver to remove the lid from the clutch master cylinder (you do not want to strip those delicate little screws);
  • a new unopened container of DOT4 brake fluid;
  • a vacuum brake bleeder tool;

[/FONT]
View attachment 179996[FONT=&amp]
Above: all the tools & supplies needed to remove and replace an ST1300 clutch slave cylinder.

[/FONT]
View attachment 179998[FONT=&amp]
Above: close-up of the 12 mm ring-ratchet wrench and the 8 and 10 mm flex ring ratchet wrenches you'll need.

[/FONT]
View attachment 179997[FONT=&amp]
Above: an inexpensive manual vacuum brake bleeder tool. I got this one at Princess Auto (equiv. to Harbour Freight in the US - worked like a charm). It is regularly $69.99 CDN but I got it on sale for around half that and well worth the full price IMHO. Note the fluid in the Heinz ketchup bottle - that is all we got from the clutch hydraulic system.

GETTING ACCESS - STAGE 1
[/FONT]

  • [FONT=&amp]start with the bike [/FONT]on the centre stand;
  • drape the fuel tank & fairing area to protect it from the inevitable spill of brake fluid
  • [FONT=&amp]disconnect the battery (you do NOT want some helpful passer-by to hit the starter during this procedure);
    [/FONT]
  • remove the black belly fairing panels (no other fairing panels or exhaust parts need to be removed) - requires a 5 mm Allen key;[FONT=&amp]
    [/FONT]
  • [FONT=&amp]remove the oil filter (it makes access to the CSC much easier) you will loose about half a litre of engine oil - so you'll need a drain pan;
    [/FONT]
  • [FONT=&amp]using the vacuum brake bleeder - drain the clutch hydraulic system (you will likely be surprised at how little fluid comes out) - this requires a 10 mm ring ratchet wrench;
    [/FONT]

GETTING ACCESS - STAGE 2

  • now put the bike on the side stand - access is not wonderful, but its OK (NOTE: a hoist would NOT help IMHO and laying it right down on the left side might make things easier but we did OK on the side stand);
  • [FONT=&amp]mark[/FONT] the position of the gearshift linkage on its splined shaft (I used a little stripe of typewriter correction fluid painted across the shaft and link to mark the correct position);[FONT=&amp]
    [/FONT]
  • [FONT=&amp]remove the pinch bolt that secures the gear shift linkage to the transmission shift-shaft and remove the linkage itself - requires 10 mm flex ring ratchet wrench;
    [/FONT]
  • [FONT=&amp]fold the gear shift linkage out of the way (DO NOT touch the other end of the linkage that connects to the shifter pedal on the LH side of the bike);
    [/FONT]
  • [FONT=&amp]there are 3-4 hoses held within a sheet metal bale that is bolted to the rear case of the engine - slip those hoses out of the bale and lash them out of the way (you can see the sheet metal bale in one of the photos below);
    [/FONT]
[FONT=&amp]
[/FONT]
View attachment 180001[FONT=&amp]
Above: accessing the clutch slave cylinder from the right hand side of the bike - while it is on the side stand. The nice warm sun made it a little more bearable.

[/FONT]
View attachment 180002[FONT=&amp]
[/FONT]
[FONT=&amp]Above: we found that working with one hand above the right hand side exhaust pipes and the other below the pipes seemed to work OK. You can see that the banjo bolt and the three (3) crush washers have been removed.

[/FONT]
View attachment 180003[FONT=&amp]
Above: access is not great - but its OK. The person's hand is on the CSC and you can see the mounting boss for the oil filter, the sheet metal hose bale and the gear shift linkage dangling down (note the iron ring - he's a Canadian engineer).

REMOVAL of the CLUTCH SLAVE CYLINDER
NOTE
: you may get some brake fluid dripping down in this set of steps so keep a rag handy and be careful not to get any in your eyes!
[/FONT]

  • first loosen the banjo bolt which secures the two hydraulic fittings to the top of the clutch slave cylinder and pull it straight up and out - requires the 12 mm flex ring ratchet wrench;
[FONT=&amp]
  • remove the three (3) crush washers from between the fittings -
  • NOTE: one washer goes between the lower fitting and the CSC, the second goes between the two fittings and the third goes between the head of the banjo bolt and the top of the upper fitting;
  • DO NOT REUSE the CRUSH WASHERS;
  • remove the three 6 mm bolts that secure the clutch slave cylinder to the engine case - requires the 8 mm 1/4" drive socket & ratchet;
  • NOTE: now you will likely get some brake fluid coming out - that is the fluid that has leaked past the seal in the CSC and the reason you're having all this fun!);
  • clean the area around the CSC mounting pad and inside the cavity in the engine case - particularly the end of the clutch push rod;
  • be sure to remove all of the old gasket - this can be laborious;

INSTALL the NEW CLUTCH SLAVE CYLINDER
[/FONT]

  • put the new gasket (Honda p/n 22862-MGJ-D00) on the new clutch slave cylinder (Honda p/n 22860-MCS-000) ;
[FONT=&amp]
  • NOTE: there are two dowels (Honda p/n 94301-08100 - its called a Pin Knock 8x10) in the CSC body that align the assembly with the cavity in the engine case: be sure they're both in place before inserting the three 6 mm bolts;
  • put a small amount of high temperature silicone grease into the pocket in the cylinder which engages the clutch push rod;
  • install the new CSC with three 6 mm bolts (Honda p/n 96001-0602200 - its called a Bolt Flange, 6x22) - and tighten - requires the 8 mm 1/4" drive socket & ratchet;
  • put a small dab of Vaseline on a NEW crush washer (Honda p/n 90545-300-000 - its called a Washer - Oil Bolt) and insert it between the lower of the two hydraulic fittings and the CSC and repeat for a second crush washer placing it between the lower and upper hydraulic fittings and finally, repeat again for the third crush washer and thread that washer onto the banjo bolt - and slide the bolt down through the washer-hydraulic fitting assembly;
  • NOTE: this task is a heck of a lot easier to say than it is to do - but work methodically and you'll get it; BE SURE that the banjo bolt thread starts properly before you get on it with the wrench.
  • tighten the banjo bolt-hydraulic fitting-crush washer assembly - requires the 12 mm ring ratchet wrench (a flex version may be better here);

WRAPPING UP
[/FONT]

  • re-install the gear shift linkage- being sure to get it on the correct spline on the shifter shaft (aren't you glad you used the typewriter correction fluid to mark it?);
  • re-install the hoses into the sheet metal bale and be sure they are not pinched;

Put the bike back up on the centre stand for the remainder of the task;
  • re-install the oil filter (I suggest using a new one);
  • check oil level: it will likely be at the bottom of the safe range - add to correct level;
  • bleed the clutch hydraulic system (and don't spill any brake fluid on anything you care about) - requires the 10 mm ring ratchet wrench and the vacuum bleeder tool;
  • re-install the belly fairings;
  • re-connect the battery;
  • start the bike and test the function of the clutch and observe for leaks;
[FONT=&amp]
That's it - you're done! [/FONT]
:D Its time for a tastey BEvERage I would say.[FONT=&amp]

I don't think I have forgotten anything but if I have, please point it out in a PM and I will correct the post. I wish I had more photos, but frankly, it is so tight in there that taking them wasn't really feasible.

Cheers,

Pete[/FONT]
 
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I was unable to open any of your attachments/photos for some reason.
Sounds like you did a good job....well done!
You just lost me at the vacuum bleeder being needed :rofl1: You could have simply bleed the fluid out of the bleeder, or used a Motion Pro bleeding tool for about $15 bucks.
Now don't you feel better that you did it yourself and saved all that money for more Beverages?
I forgot to mention that you could have removed the filter and the speed sensor to get more room for your hands, my bad, sorry.
Thanks for your write up.
Igofar
 
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I was unable to open any of your attachments/photos for some reason.
Sounds like you did a good job....well done!
You just lost me at the vacuum bleeder being needed :rofl1: You could have simply bleed the fluid out of the bleeder, or used a Motion Pro bleeding tool for about $15 bucks.
Now don't you feel better that you did it yourself and saved all that money for more Beverages?
I forgot to mention that you could have removed the filter and the speed sensor to get more room for your hands, my bad, sorry.
Thanks for your write up.
Igofar
Thanks Igofar and Jim!

NWRich has also alerted me to the photo problem - don't understand it. Everything looked fine when I was drafting the post. Good point on the speed sensor - hadn't thought of that either. Also, I'm not familiar with the Motion Pro bleeder - I'll have to check that out.

Anyhow, we have guests sleeping in the basement where my computer is located so I won't be able to fix it till later this AM. Stand-by please.

Pete
 
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Hi again: I just checked out the little Motion Pro bleeder tool and while it would good for bleeding the air at the end of the job, I don't think it would help to drain the clutch hydraulic system in the first place.

THAT was where the vacuum brake bleeder really helped.

Pete
 

ibike2havefun

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NWRich has also alerted me to the photo problem - don't understand it.
Maybe it's a permissions problem? If the photos or attachments are in a place that does not grant general public access that would do it. Maybe one of the moderators can help diagnose the issue- it would certainly be beneficial to see the photos that go with your great write-up.
 
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Maybe it's a permissions problem? If the photos or attachments are in a place that does not grant general public access that would do it. Maybe one of the moderators can help diagnose the issue- it would certainly be beneficial to see the photos that go with your great write-up.
i doubt that is because the missing photos were taken by me on my phone. They looked fine as I drafted the post, but disappeared when I submitted it. I'm in touch with Joe and we'll sort it out.
 
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Hi All:

I have fixed the post including getting the pictures to appear and have posted it in my original thread on this topic because I felt that future readers would be searching for the key words Clutch Slave Cylinder. The thread is ST1300 Clutch Slave Cylinder Replacement and here is a linky to the post:

https://www.st-owners.com/forums/showthread.php?155031-ST1300-Clutch-Slave-Cylinder-Replacement&p=1994238#post1994238


I`d be happy to help anyone planning to do this job - just PM me and we can have a chat.

Cheers,

Pete
 

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Sounds more like your clutch/springs have gone south for the winter. But I do know how much you like wrenching on these bikes :rofl1:
Well, I figure that will be the "next" course of action, but I still think that the CSC has a leak.
 
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Hi again: I just checked out the little Motion Pro bleeder tool and while it would good for bleeding the air at the end of the job, I don't think it would help to drain the clutch hydraulic system in the first place.

THAT was where the vacuum brake bleeder really helped.

Pete
We will have to agree to disagree on the vacuum bleeder....again, not needed. I have used the MP tool to bleed brakes, clutches, and any system that uses hydraulic or brake fluid without problems.
Most folks that try it never go back to using the vacuum bleeder again. What do you think would happen if you simply put a clear tube on the clutch bleeder, opened the valve, and pumped the clutch lever till all the fluid drained out :rofl1:
Finally saw the photos, good job!
 
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We will have to agree to disagree on the vacuum bleeder....again, not needed. I have used the MP tool to bleed brakes, clutches, and any system that uses hydraulic or brake fluid without problems.
Most folks that try it never go back to using the vacuum bleeder again. What do you think would happen if you simply put a clear tube on the clutch bleeder, opened the valve, and pumped the clutch lever till all the fluid drained out :rofl1:
Finally saw the photos, good job!
OK - not to be argumentative, but I do not understand how, once the master cylinder is empty - how pumping the lever pushes the remaining fluid out of the bleeder nipple...

The MP tool does indeed look very useful for bleeding air out of a filled system - IF it has fluid to use. The advert even says that it won`t work on a `dry` system (i.e. on where there is no fluid).

hmmmmmmm......
 
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OK - not to be argumentative, but I do not understand how, once the master cylinder is empty - how pumping the lever pushes the remaining fluid out of the bleeder nipple...

The MP tool does indeed look very useful for bleeding air out of a filled system - IF it has fluid to use. The advert even says that it won`t work on a `dry` system (i.e. on where there is no fluid).

hmmmmmmm......
I'm sorry, I was not trying to be argumentative, I think you did a good job repairing your bike.
The MP is simply a check valve that only lets fluid go in one direction, and yes, you need some fluid in the lines to build up pressure to work, however, what if.....you didn't drain the master cylinder first, then simply opened up the bleeder valve, and pumped all the fluid out through the bleeder? Would this not do the same thing?
Several ways to skin a cat, yours worked, and you should feel proud that you did it yourself and saved alot of money.
 
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I'm sorry, I was not trying to be argumentative, I think you did a good job repairing your bike.
The MP is simply a check valve that only lets fluid go in one direction, and yes, you need some fluid in the lines to build up pressure to work, however, what if.....you didn't drain the master cylinder first, then simply opened up the bleeder valve, and pumped all the fluid out through the bleeder? Would this not do the same thing?
Several ways to skin a cat, yours worked, and you should feel proud that you did it yourself and saved alot of money.
Not to worry, I suspect we're in violent agreement on several points. My issue is that once the master cylinder has no fluid, it cannot push any more and yet you'd still have fluid all the way down the line and inside the slave and even down the bleed line. The whole idea is to drain the entire system so that it doesn't come running out into your eye when you take things apart.

I doubt that the master would push air and I also suspect that surface tension and fluid friction inside those tiny lines would stop all that fluid from running out the bleed line.

Anyhow - next time, I'm going to try your idea - it would certainly save some time. All good!

Cheers,

Pete
 
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Lost my clutch pressure the other day. Reservoir almost empty. Did what everybody is suggesting as far as bleeding it. But while doing it i saw the brake fluid leaking from underneath the bike out of the drain hose that's closer to the front. What kind of problem am i looking at ? Clutch slave seal ?
 
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What drain hose "closer to the front" are you talking about? Pictures will help us help you.
 

Mellow

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Lost my clutch pressure the other day. Reservoir almost empty. Did what everybody is suggesting as far as bleeding it. But while doing it i saw the brake fluid leaking from underneath the bike out of the drain hose that's closer to the front. What kind of problem am i looking at ? Clutch slave seal ?
Yeah, if you're bleeding it and it's leaking it more than likely the clutch slave.
 
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I'm not home right now, but it's not the two that's tied together towards the back but the one that's thicker closer to the front tire. Also not sure if it's leaking out of it or just running down on it.

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Mellow

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Thank you Mellow

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Might be a fitting or something also... you need to confirm that. Probably need to remove the plastic to get a better look.
 
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