Clutch Woes! (Page 2/2)
Dukesterpro AUG 22, 01:04 PM
I'm back again, this Fiero has me on my wits end.

I have already email Rodney regarding the issue, and he has already responded about replacing my failed parts, so please be clear this is NOT me criticizing Rodney's parts, I am 99.999% sure this was an installation user error. I only want to disclaim this so no one thinks trying to imply anything other than that I am messing up something somewhere.

84 Fiero SE, Muncie 4spd.

Anyways, I went ahead and added a 50/1000s shim to my flywheel, reinstalled and still found I have no clutch throw. I bit the bullet and purchased Rodney's master with adjustable banjo and slave. This is what happened.

Prior to installing the Master/Slave. I was unable to get enough throw at the clutch arm to disengage the clutch. I ordered a new Steel Pedal from the Fiero store and installed it without the redundant return spring. I then installed bench bled the Master cylinder per the included instruction and installed it with my old slave cylinder, I had the adjustable banjo turned out approximately 2 turns longer than the stock push rod and of course have the banjo facing up. I bled per V8 Archies instructions. (Pedal Down, Crack Bleeder, Close Bleeder, Pedal Up. Repeat. Upon the last bleed cycle remove the bleeder, push the piston back. Close bleeder release.) This allowed the car to shift, however the clutch wont disengage until the absolute bottom of the pedal travels. You have to push it hard into the floor to get it to shift. I figured that this was a result of using my old Slave (even though the old slave showed no signs of leakage) so the following day I replaced my old slave with your new one. I repeated the same bleeding procedure, after the bleed was complete, I ended up with less throw (15/16th of inch vs 1 1/16) than with the old slave. Figuring that this was a result of a poor bleed I kept attempting to bleed and rebleed with no results. I immediately noticed that the piston on the master was coming up very slowly during the bleed process, frequently getting stuck down and taking 30+ seconds to return. I also noticed fluid in the boot of the slave cylinder a little bit after the master began to stick down. After removing it to see where the leak was from, I noticed the piston can slide right out the end, and appears to be lacking a snap ring. I decided to put my old slave back on but determined the master was now stuck down and the pedal was not coming back up.

I am using Prestone DOT3, if that's relevant.

I am using a LUK Clutch with a resurfaced stock flywheel and a 50/1000s shim. I have noticed that when the slave is removed I have about 2 inches of play at the throw-out bearing if I pull it away from the pressure plate. I can push the throw-out against the pressure plate fine. This has been mentioned to be normal to me, but I figured its worth mentioning.

My clutch arm is not cracked, and my fork is new with new bearings and a new seal.

Tell me Fiero people, what am I doing wrong? I just cant imagine there is enough air in that system to be short 2 inches of pedal throw and have the actuation point on the floor. I'm getting desperate here, haha. I just want to get more opinion before continuing.
fierofool AUG 23, 03:47 PM
A couple of questions just for more info. If I recall, the 84 used a different slave than any of the other years. There were 4 different length slave pushrods. One for the 84 4-speed, one for the 85-86 4-speed, one for the 85-88 Isuzu, and one for the 86-88 Getrag. Are you sure you have the correct slave pushrod? If it's too short, your slave will bottom out before the clutch releases.

Edit: To correct what I said about the different pushrods. The 85-86 4-speed and the 85-88 Isuzu slaves were the same and used the same length pushrod, so there were only 3 different lengths. Rodney says his 85-86 pushrods are 144mm long while the 84 pushrod is 138 mm long.

When shimming the flywheel, the shim thickness should be equal to the amount cut from the face of the flywheel.

[This message has been edited by fierofool (edited 08-23-2022).]

Dukesterpro AUG 23, 04:22 PM
I can not confirm that I am using the correct pushrod, but I can confirm that the replacement pushrod from RD is the exact same length as the one that was there previously. My old slave is actually aluminum, my understanding is that 84s have aluminum slaves originally. During my disassembly it appears that nothing on this Fiero has ever been removed regarding its clutch, which seems likely due to the low miles. I can confirm that the old slave, which I verified has a snap ring, does not leak or bottom out when operating the clutch. I confirmed this by detaching the pushrod and stepping the pedal which goes solid as soon as the slave bottoms out.

The shim I installed is thicker than the amount of the flywheel taken off. My understanding from previous cars where I have shimmed flywheels is that the shim must be the same or greater (to a limited amount) than what was removed. I removed about a total of 40/1000s of material and the shim is confirmed at 50/1000's
Patrick AUG 23, 05:26 PM

quote
Originally posted by Dukesterpro:

I ordered a new Steel Pedal from the Fiero store and installed it... I had the adjustable banjo turned out approximately 2 turns longer than the stock push rod...



I understand that the possibly defective RD master and slave units have momentarily put things on hold, but I have a question about your banjo length.

Ordinarily an adjustable banjo is used to compensate for a bent clutch pedal. It allows a certain measure of lost throw to be recovered. When you lengthened the adjustable banjo to be "2 turns longer than the stock" with a new clutch pedal, were you still allowing for some free play at the top of the pedal's travel? Is it possible you lengthened the banjo too far and the clutch master wasn't able to fully return to the end of its travel? In other words, is it possible that the master was never being fully released?

[This message has been edited by Patrick (edited 08-23-2022).]

crashyoung AUG 27, 02:29 AM
I read all of your replies and think I know what you are going through.

My 86 clutch was replaced with similar problems, and I went through several different paths trying to get it working, including replacing the slave cylinder.

I ended up using a vacuum pump to draw the DOT3 fluid into the slave from the master. It took two people to get it done, but it was near perfect afterwards.
One person watched the fluid drawn out of the slave cylinder into a catch bottle, while the other person kept the master filled with new DOT3.

Once the system was opened, and the new slave was installed, the amount of air that had to be removed was the tripping point. Trying to do the job myself meant that occasionally the master would run out of fluid, and the air would be in the line again! By having a second person to fill the master, while the other watched for bubbles in the catch bottle allowed the pump to be turned off when no more air was detected.

I think I wasted about a gallon of DOT 3, but the system was clean and water free afterwards!

I don't look forward to the job it will be after I do a 3800 swap into that car....

About resurfacing the flywheel, I do that every clutch change, but I have two flywheels I use to ease the job. Once I have the 3800 installed I will have two spares for the 2.5L.

[This message has been edited by crashyoung (edited 08-27-2022).]

Patrick SEP 03, 04:06 PM

quote
Originally posted by Dukesterpro:

Pulling my Hair out!



Still? Or has this been resolved?
Dukesterpro OCT 07, 04:45 PM
For anyone with this issue, this was my fix.

The bolts holding the entire pedal assembly worked there way loose and the whole assembly was flexing with the pedal. Bolted them babies down tight and low and behold clutch works good!. I did end up needing that spacer! For anyone planning on having there duke flywheel resurfaced!