Clutch Master and Slave cylinders

Info: when they added an intercooler for the 85.5 model, they upgraded the transmission in several ways.  The 83-87 non-intercooled (ALL flatsider cars except the 85.5) transmissions have a thicker throw-out bearing and a longer rod on the slave.  One of those many changes was a thicker plate in the front and this moved the pivot ball for the fork forward so that rod and throw out (release) bearing were both made 5mm thinner (shorter).  You CAN NOT mix and match parts you have to use both short parts for the intercooled transmissions.  For 1983-1987 flywheel is drilled for a pressure plate and clutch disc of 225mm.  The 1988/89 flywheel is drilled for a pressure plate and disc of 240mm.  The intercooled Vs non-intercooled has an overlap from the years 85.5-87 and that makes for confusion when picking a clutch "kit".  Most would think that there are only two clutch kits when there are actually three.  Some brands may not completely identify the parts in their "kit" and you will end up with the wrong throw out bearing.  You can put an 88/89 flywheel on any year car and you can also put the 83-87 wheel on any car but the disc and pressure plate is always going to be related to the bolt pattern of the flywheel and the throw out bearing and slave rod length will always be related to the transmission CASE and not the flywheel.

The slave cylinders are the same for all years only the rod is different.  If you can buy an 84 slave cylinder for half the cost of an 89 then buy it and use your old shorter rod.  At rest both throw-out bearings will be in contact with the clutch plate fingers.  The fork and pivot ball did not change. 

You can see the difference in the two parts below.

Slave cylinder internals.  Those are both c/s slave parts just one old and the other new.  A Raider used a different part for #16.  We removed both part #15 and #16 on this car.  Part #16 is a restrictor of sorts acting on the tip of the banjo bolt where the fluid enters then isn't allowed to escape as quick as it could if that part was left in so we deleted them.  Seems to be working fine you may want to experiment with this yourself.  I haven't seen the Raider part #16 to see the difference in the size of that restrictor opening.

A Conquest/Starion is type 24, the parts in question:

MD603469 & MD603468

Clutch master cylinders are the same for a few different Mitsubishi built vehicles, you are looking for a 5/8" bore cylinder and that plastic cap on the end for the fluid hose or reservoir can be reused from your old part.  For example if you find a master for a 1988 Colt get it, its the same you just can't use its reservoir but if it just has the cap with a hose barb sure you can use it and it may be half the price.

You have a transmission that doesn't shift well, may tend to grind when you put it into gear or not like to shift well at high rpms and when shifting quickly?  If you have worn linkage you won't be able to because that's just like not depressing the clutch pedal completely.  The bracket on the end of the clutch master wears out where it fastens to the clutch pedal using a pin.  The pin may also be worn and perhaps the hole in the pedal.  The upper pivot of the pedal in the bracket that is attached to the firewall does wear out.  If you hear a click sound when the pedal is partially down that's a sign that the upper pivot is worn and as the pedal gets about half way down there is an assist spring that helps out and the slop in the pivot joint causes the pin on the pedal to shift to the opposite side of the (worn) hole.

Here's the master part that wears, new Vs used.  That seemingly small amount of wear translates to a great deal of loss in slave rod travel.  You can replace just this bracket but you might as well replace the entire assembly.

Other wear points for a HD pressure plate.  Even with a replacement part, with a HD clutch this can quickly wear again if the pin is worn and you didn't apply some heavy grease to the pin.  The insert that is threaded can be weakened and fail if your pedal ends up at the bottom of the floor against the carpet when the bump stops for the pedal are missing and the rod is extended out too far.

1984

Brake Pedal                                       Clutch Pedal

Apply grease in a film, don't get too much so that it gets on the input shaft or it will fly off and contaminate the surfaces or your pressure plate and clutch disc.

Don't put the disc in backwards, the hub on most discs usually is not in the center its offset to one side and that must go to the tranny side or you'll push down the clutch pedal and you won't be able to shift gears.  The fingers are already loaded up from the hub hitting the flywheel and the disc isn't making contact so it will slip after the metal grinds away.

If you wish to flush your transmission case you will have to remove the pan, its a good idea at this time to replace the input and output shaft seals.  This is what you'd find after you flush the gearbox.  Use a non water based cleaner and a parts washer gun connected to a pressure washer or air compressor makes this easier.  Pour some gear oil on the parts before you put the pan back on, put in the gear shifter and move it through the positions.  DO NOT move the forks by hand without using the shifter, you can cause them to be out of position and if you put the pan back on and the shifter back in the shifter may be stuck.