HELP! Rebuild of 1992 907ie clutch master cylinder

discussions specific to the 907IE
schneekloth
Posts: 5
Joined: Thu Aug 01, 2013 1:34 pm
model: 907 I.E.
year: 1992
Location: USA

HELP! Rebuild of 1992 907ie clutch master cylinder

Post by schneekloth »

All, I recently lost all pressure on my clutch master cylinder, so my bike jumped forward when I changed into first gear. Luckily, I had the brake pulled:-) Anyway, after trying multiple bleeds and refills, I finally gave in and located a Brembo 98.5029.70 rebuild kit that contains all of the parts needed for the typical rebuild. I was able to partially remove the clutch cylinder from the handle bar (i'm not the most mechanically inclined person) and then proceeded to remove the old pieces, the spring, bolt o-ring, etc. While I was careful to remove everything without breaking it, I did use pliers to remove some of the parts. Unfortunately, I am now unable to figure out in what exact order the rebuild kit pieces go back in to the master cylinder. I printed out the old manual and workshop manual, BUT the info is not pictured clearly enough and it is also showing a piece not part of the actual master cylinder nor the rebuild kit. Specifically, I have all the new parts to replace the old parts but cant figure out in what order and how tog et them in there. It seems there is one crucial piece of order related to the larger rubber piece and some type of metal crush washer? I can provide pics as needed, but I really need help getting this sorted today or tomorrow. I need to ride the bike out of a storage building and back to my house. Everything else works:-( Thanks for any assistance.
Martin

1992 Ducati 907i.e. Black
1978 Vespa P150X Blue/Grey
1977 Vespa P200E Red
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

from the P750 FAQs
Clutch Master Rebuild

Clutch master cylinder failure is characterized by a relatively sudden loss of clutch stiffness. It can give little or no warning as to its impending failure.
The procedure to rebuild the master cylinder is relatively simple, and only requires a minimum of tools. A clean space to work and some patience is most important.

You will need Ducati part 000047226, which I obtained for approximately $25us. The dealer informed me that there is a price increase on the way which could raise it as high as $60us.

The procedure for this rebuild is outlined below

WARNING
Brake fluid can damage the paint on your Paso. Have a rag under your work area at all times!

1. Drain all fluid from the reservoir.
2. Remove banjo bolt from back of master cylinder that leads to clutch fluid tube.
3. Remove choke cable from choke lever.
4. Remove 2 allen bolts that retain master cylinder/lever assembly and withdraw the unit.

Gather up the following tools (shown from left to right) and find a clean place to work. You will also need a bottle of new brake fluid.
19mm wrench
medium phillips screwdriver
medium slotted screwdriver
very small slotted screwdriver
strong pick (like a dentist uses)
14mm socket

5. Using 19mm wrench, remove the lever retaining nut from the bottom of the assembly.
6. Push out the retaining pin and remove the lever from the assembly.
7. Spin the choke lever off it's mount, and remove the mount from the assembly.
8. Remove the pushrod from the dust seal in the now exposed end of the cylinder.
9. The seal will need to be picked out as much as possible to proceed. Be careful not to damage the inside of the cylinder.
10. After most or all of the seal has been removed, the piston and spring should drop free. Take note of which direction the spring faces in the assembly.
11. The seal and plastic bushing and o-ring are retained within the assembly with a press-in ring. There is a small hole in the side of the bore behind this ring, and with careful use of the small screwdriver, the ring can be distorted enough to remove easily. Also take note of which direction the plastic bushing faces.
12. Ensure that the o-ring is also out of the bore, and lay out the parts that you removed.
13. Lay out the new parts next to the old ones and make sure that they are all there. You will need to assemble the piston with the brass washer and seal, and the piston receiver will need to be inserted into the end of the spring.
14. Carefully flush out the bore with clean brake fluid.
15. Install the new o-ring in the groove.
16. Insert the spring, receiver side up.
17. Grease the piston and CAREFULLY slide it seal first into the bore.
18. Now comes the tricky part. The piston must be compressed, while the plastic bushing, dust boot, and press-in ring are all installed. I found that the best way to do this was to slip the dust seal over the plastic bushing, followed by sliding the press-in ring over the dust boot. Now, slip your 14mm socket onto the phillips screwdriver, then CAREFULLY slide the screwdriver into the hole in the end of the dust seal. Holding this assembly together, use the end of the screwdriver to compress the piston, whereas the retention/dustboot assembly should drop neatly into place.
19. GENTLY tap (the wrench works nicely) on the socket to drive the retention ring home.
20. Remove the screwdriver and socket, and put the pushrod into place.
21. Re-install the pin and clutch lever.
22. Pour about 1/4" of new brake fluid into the reservoir, and gently prime the cylinder.
23. Re-install the choke mechanism.
24. Pour yourself a pint of Guinness, and marvel at your work!
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

.
Attachments
IMG_14371.jpg
IMG_14371.jpg (100.23 KiB) Viewed 12067 times
IMG_1437.jpg
IMG_1437.jpg (232.77 KiB) Viewed 12067 times
schneekloth
Posts: 5
Joined: Thu Aug 01, 2013 1:34 pm
model: 907 I.E.
year: 1992
Location: USA

Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by schneekloth »

Thanks so much for the quick reply, I will get to it this afternoon, beer pint in hand, but for after:-)

paso750 wrote:from the P750 FAQs
Clutch Master Rebuild

Clutch master cylinder failure is characterized by a relatively sudden loss of clutch stiffness. It can give little or no warning as to its impending failure.
The procedure to rebuild the master cylinder is relatively simple, and only requires a minimum of tools. A clean space to work and some patience is most important.

You will need Ducati part 000047226, which I obtained for approximately $25us. The dealer informed me that there is a price increase on the way which could raise it as high as $60us.

The procedure for this rebuild is outlined below

WARNING
Brake fluid can damage the paint on your Paso. Have a rag under your work area at all times!

1. Drain all fluid from the reservoir.
2. Remove banjo bolt from back of master cylinder that leads to clutch fluid tube.
3. Remove choke cable from choke lever.
4. Remove 2 allen bolts that retain master cylinder/lever assembly and withdraw the unit.

Gather up the following tools (shown from left to right) and find a clean place to work. You will also need a bottle of new brake fluid.
19mm wrench
medium phillips screwdriver
medium slotted screwdriver
very small slotted screwdriver
strong pick (like a dentist uses)
14mm socket

5. Using 19mm wrench, remove the lever retaining nut from the bottom of the assembly.
6. Push out the retaining pin and remove the lever from the assembly.
7. Spin the choke lever off it's mount, and remove the mount from the assembly.
8. Remove the pushrod from the dust seal in the now exposed end of the cylinder.
9. The seal will need to be picked out as much as possible to proceed. Be careful not to damage the inside of the cylinder.
10. After most or all of the seal has been removed, the piston and spring should drop free. Take note of which direction the spring faces in the assembly.
11. The seal and plastic bushing and o-ring are retained within the assembly with a press-in ring. There is a small hole in the side of the bore behind this ring, and with careful use of the small screwdriver, the ring can be distorted enough to remove easily. Also take note of which direction the plastic bushing faces.
12. Ensure that the o-ring is also out of the bore, and lay out the parts that you removed.
13. Lay out the new parts next to the old ones and make sure that they are all there. You will need to assemble the piston with the brass washer and seal, and the piston receiver will need to be inserted into the end of the spring.
14. Carefully flush out the bore with clean brake fluid.
15. Install the new o-ring in the groove.
16. Insert the spring, receiver side up.
17. Grease the piston and CAREFULLY slide it seal first into the bore.
18. Now comes the tricky part. The piston must be compressed, while the plastic bushing, dust boot, and press-in ring are all installed. I found that the best way to do this was to slip the dust seal over the plastic bushing, followed by sliding the press-in ring over the dust boot. Now, slip your 14mm socket onto the phillips screwdriver, then CAREFULLY slide the screwdriver into the hole in the end of the dust seal. Holding this assembly together, use the end of the screwdriver to compress the piston, whereas the retention/dustboot assembly should drop neatly into place.
19. GENTLY tap (the wrench works nicely) on the socket to drive the retention ring home.
20. Remove the screwdriver and socket, and put the pushrod into place.
21. Re-install the pin and clutch lever.
22. Pour about 1/4" of new brake fluid into the reservoir, and gently prime the cylinder.
23. Re-install the choke mechanism.
24. Pour yourself a pint of Guinness, and marvel at your work!
Martin

1992 Ducati 907i.e. Black
1978 Vespa P150X Blue/Grey
1977 Vespa P200E Red
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

this shows the Ducati #000047226 repair kit and the order it`s installed (looks a little different compared to what the manuals show)
Attachments
000047226_1.jpg
000047226_1.jpg (102.71 KiB) Viewed 12065 times
000047226_2.jpg
000047226_2.jpg (45.66 KiB) Viewed 12065 times
schneekloth
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year: 1992
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by schneekloth »

Thanks for all the feedback, it allowed me to complete the rebuild with the Brembo kit without any problems. Unfortunately, it did NOT resolve by problem. After install and filling up with fresh fluid and bleeding appropriately and building proper pressure, the bike still jumped when I shifted into first gear, showing that the clutch was still not engaging when pulled. I'm out of ideas, what could be the issue here, it's not at the master cylinder or clutch lever. Please help!
Martin

1992 Ducati 907i.e. Black
1978 Vespa P150X Blue/Grey
1977 Vespa P200E Red
nickta
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by nickta »

Hi Martin.

Only thing left is the slave cylinder. Rebuilt kit available from your friendly neighborhood Ducati dealer or replace the whole lot with an aftermarket unit.

Cheers
Nick.
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

I'm thinking of something different.
You said you need to get the bike out of the storage building so I take it the problem did occur after a longer storage and not during a ride.
Remove the clutch cover, pull and release the clutch to see if the clutch discs move freely or if they stick together.
You could remove all clutch discs and clean them with sandpaper.

If that isn't it I'd check the slave cylinder next but if that was not ok it would probably leak, wouldn't it?
schneekloth
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by schneekloth »

So the symptom for that could be the bike jumping into first gear when depressing/pulling the clutch lever? It did sit in storage for about 4 months when the issue occurred.
paso750 wrote:I'm thinking of something different.
You said you need to get the bike out of the storage building so I take it the problem did occur after a longer storage and not during a ride.
Remove the clutch cover, pull and release the clutch to see if the clutch discs move freely or if they stick together.
You could remove all clutch discs and clean them with sandpaper.
Martin

1992 Ducati 907i.e. Black
1978 Vespa P150X Blue/Grey
1977 Vespa P200E Red
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

if the clutch discs or some of them stick together the clutch won`t disengage. Have to admit that 4 month is not really a long time for that to happen. Still worth checking.

PS: late afternoon in the US, early morning in Australia, after midnight here. I'm off. Good luck!



------------------------------
1986 Vespa T5 125 ;)
*MB
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by *MB »

Hi Martin,

You haven't mentioned when your clutch was last checked/overhauled, or for that matter where your clutch lever used to engage gear drive and how it engaged prior to storage?

Several things spring to mind... I would check the clutch basket for notch wear, along with clutch pack stack height, and clutch pack layout.

In terms of the basket look for notching along the edge where the clutch plates make contact/drive. If excessively worn it could be hanging up the plates from moving smoothly.

If the basket is fine then check the clutch pack stack height, plate condition, and check placement of the spring plates within your clutch stack. In particular the spring plates placement within the stack can make quite a difference in terms of snatch. I have seen several different spring plate placement configurations in that regard.

Cheers,

Marc
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

When you have checked the clutch and didn't find a problem remove the slave cylinder. I would expect it to be dry (other than maybe some grease there should be no brake fluid). What you can try is to hold the cylinder in one hand pressing the thumb firmly on the piston while carefully pulling the clutch lever. You should feel pressure building up againt your thumb. You can let the piston move out a few millimeters. Do not take your thumb off the piston before you let the lever go! (or it will pop out)
If there is no or little pressure or you can feel it decrease there could be air in the system or one of the clutch cylinders could be faulty. If the slave cylinder leaks while you do the test it's clear. If it doesn't the problem must be in the master cylinder (although you just rebuilt it).

When you dis-/reassembled the clutch master cylinder did you turn the lever adjustment screw? If you did you may have changed the lever stroke and it could be too short. (that screw should be left alone unless it's really necessary to make a change)
H20doctor
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by H20doctor »

sounds like the slave cylinder , mine was blown and leaking fluid when it failed... but i had the same issues , no pressure on the clutch lever , and it wouldnt shift at all.. and jump hard when i put it into 1st gear
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paso750
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Re: HELP! Rebuild of 1992 907ie clutch master cylinder

Post by paso750 »

how did this story end?
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