Leaking clutch master?

[zhong]

Could you elaborate? I'm not sure on what grounds you base these comments on.

Why certainly.

1 SHIFTING

Technical Service Bulletin 00-055 (Transmission/Driveline) for Grinding When Shifting into 2nd Gear. Honda says this applies for certain �00 S2000's, this revision changes applicability and parts and warranty claim information. Some owners that have had this repair claim it doesn�t always work. Other owners report shifts being notchy going into 1st and 3rd gears as well. It�s unclear at this time if the reported improvements in �02 S2000s have corrected the problem - it would appear not. Several owners report the grinding condition may be trigger by hotter weather, i.e., 100 degrees +. Some owners report a transmission fluid change has improved the notchy feel.
Demands on the S2000 syncro�s as explained by a Honda engineer, and his suggestion for taking care of them: Since the engine revs to 9000 rpms, it means the transmission mainshaft and clutch disk are also revving to 9000 rpm. When you push in the clutch pedal to disengage the clutch and shift from 1st to 2nd the engine and the transmission are disconnected. At the same time, the engine slows down from compression as you lift off the throttle. The transmission mainshaft, no longer connected to the engine, is freewheeling in the transmission. Given enough time the mainshaft will slow down but not as fast as the engine. The countershaft is connected to the rear wheels and the speed stays constant during the shift. When you shift into 2nd gear the 2nd gear synchro must �slowdown� the transmission mainshaft to match the engine speed when the shift is completed and the clutch is engaged. The transmission mainshaft and the clutch disk together weigh 19.75 lbs. (not including the pressure plate and flywheel that are connected to the engine) When you shift from 1st to 2nd at 9000 rpm the engine speed drops to 5900. That means that the little brass synchronizer rings have to push on the 2nd gear to slow the mainshaft from 9000 rpm to 5900 rpm. It not only has to slow down the mainshaft it has to do it in the time that it takes you to shift. So if you have a tendency to shift fast you may be making the sleeve blow past the synchro rings before it has a chance to do it's job and it will smash into the 2nd gear.

The early '00 cars needed a little change to the sleeve to make the synchros work a little harder. That is what the new parts in the service bulletin are for. Cars after VIN VT006255 already have the new parts. Grinding in a car produced later than 6255 is possible if the synchros have been damaged and now are not able to slow down the mainshaft properly.

Shifting without the clutch, or, shift too quickly and not letting the synchros do their job may permanently damage the gear, sleeve and synchros and make the 2nd gear grind more often. It makes sense that if your shifting at 6000 rpm, it makes the engine speed drop 1700 rpm or 4300 rpm then you should give the 2nd gear synchro twice the time to do the shift from 9000 rpm. If your car does grind once in a while you may not want the transmission removed, disassembled and a new 2nd gear put in. If it does it quite often, show it to the dealer and have it replaced. If you hesitate for another 1/2 second while putting constant pressure on the shifter while the 2nd gear synchro does it's job, I'll bet many of your cars would not grind any more.

When the owner of a new 2002 S2000 questioned the notchy feeling between 2nd and 3rd gear he was advised all was normal: � Transmission shift mechanism inside has very short throws with rods and detents. These shift rods are held into correct position by detent balls with stiff spring pressure to prevent transmission from slipping out of gear during acceleration. Transmission function is correct at this time and no repairs are recommend by Honda Techinical Assistance. The 2002 S2000 Transmission was assembled with update parts. No updates or TSB's apply to this vehicle."

Honda put out this letter in February 16, 2000 in Portugal. Subject: Honda S2000 Gearbox
Dear customer, Honda has detected that, in some Honda S2000, the gearbox may malfunction. The symptom is difficulty in engaging 1st or reverse. This situation may occur due to a deficient lubrication inside the gearbox. Normally, this deficient lubrication only happens after driving for sometime at high speed. To correct this situation, we would like to install a modified gearbox in your vehicle, so that we can ensure the correct operation of the transmission. [This is a situation that affected early S2000s] .

For the actual TSB, click here.

Peace.

[9large]

Thanks for posting that. I believe this was the original post from s2ki: http://www.s2ki.com/forums/index.php...ic=56948&st=25.

So it appears the grinding issue may have affected some early AP1 models (pre-2001), not all.

[s2kjn]

Well i fall into the "some" category then!

[fromdeeeast]

Ok I have narrowed down what's wrong. I have realized that if I press clutch faster than usual and harder it will shift smooth and perfectly. However if I shift normal once in a while I will get a notchyness as I shift. So basically it's pressure related so it's either the clutch master or the slave master. So how do I tell which one is failing and does this sound right at all.

[tomS2KAP1]

i always park in the same spot at home, and in the mornings i start the car up for at least 3-4mins before i go
in that same spot theres not a drip of fluid no where lol

slave is leaking (eventhough, there is no sign of fluid leak on the car spot). Remove and check the slave. When I changed slave, it makes sense to change the master too.

http://www.s2ki.com/forums/index.php...#entry15397569

[philipminge]

i had same problem and it got pretty bad. i put a post up not long ago about it asking same question. was s**t as when it was cold... n about 80% of time when it was warm.... it got bad.

for me, my clutch was fair worn...so i put a new clutch in anyway n light weight flywheel.... problem still there.... SO

i replaced clutch master cylinder and bled the line and put genuine honda gearbox oil in.... feels like a new car.

problem gone............for now.....

it only did it at lower rpm... neva when revin her hard.... sometimes i have missed a gear because i got too excited n stuffed up my shift n crunched but u soon learn the limits of the car.

now she slides into gear like no tomorrow and i can change stupidly fast with no issue or crunch or rejection from gearbox.... it loves it!!! lol ..... i have a 2002 ap1 (55,000km).

i thought i was gonna go rebuild the gearbox but problem is ok at the moment.... c how it goes i guess... but maybe try what i did.

cheers