What did I break!!!
 

After the failed attempt at changing my crank pulley,
see thread here: http://www.the370z.com/engine-drivet...-pulley-2.html

My clutch pedal engagement is now very high and I want to say softer feel. Not certain on feel but definitely higher engagement.

A little back story, if you don't read the pulley thread. I had the gear in 6th and PB set while trying to break the crank pulley bolt loose, turning engine backwards. I tried 1st gear, but it engine was turning.

I put a lot of force on the breaker bar. I did hear a clunk once I released PB and put xmission in neutral after many attempts.

Anyway, changed the serpentine belt, put everything back together and went for a drive.

No noises, no gear grinding or poor engagement of gears. No clutch slippage in all phases of throttle. No CEL or others. Car seems to be driving normal.

Starting in 1st, its high engagement but I feel the clutch grab. Going from 2nd to 3 or 4th to 5th, it's high pedal engagement but I feel no definitive "grab". If I try to press gas based on my habits and middle clutch pedal engagement, obviously car will surge forward based on higher engagement.

My only guess is that I have deformed the Diaphragm springs on clutch cover.

31,000 Miles on OEM components.

Any other thoughts/suggestions?

(p.s. This is not Placebo effect. It's definitely changed :icon14:)

What action would have deformed the diaphragm spring?
The clutch was “off” during the pulley fiasco right?

The clutch issue is unrelated to the crank pulley.

Weird. I hate when coincidence sh*t like this happens.:wtf2:

Wouldn't clutch be engaged?. It's when you push pedal that it disengages.

Anyway, I don't know what would cause it to be deformed. I'm only eliminating possibilities.

The starter turns the flywheel ring gear which is attached to the crankshaft directly. I don't see how it could effect the clutch at all unless you actually worked the flywheel off, which wouldnt happen, and would cause crank trigger issues and lots of noise if you did.

It seems that he left the car in gear to hold the crank from spinning vs. using the starter and breaker bar on the ground method.

Yes, but the clutch is not between the flywheel and crank pulley. The starter leveraged the flywheel, which transferred torque through the crankshaft to the pulley bolt and tools he had wedged up. There would be no unusual stress to the clutch assembly while doing this.

From his old thread he mentioned he didn't use the starter at all, no?

He left it in gear and tried to manually loosen the crank pulley bolt with a breaker bar.

What am I missing?

Someone said they bumped the starter, I thought that was him, but I guess it was someone else that said that.

If he got it off by putting the car in gear and using the drivetrain to keep the crankshaft from rotating, than it would have loaded the clutch concentrically, like when you drive.

No Guys. I did NOT bump the starter to remove crank pulley. Another guy did.

I used transmission and PB to hold everything while I tried to undo crank shaft bolt with breaker bar.

So clutch would be engaged to flywheel.

z

That's how I did it. I had the breaker bar up between the radiator and motor. With a section of pipe on the end of the breaker bar. Had a 2" extension for the socket.

I was there too. Tried every which way. The Bugger is tight. :icon14:

Please verify/add to my progression of troubleshooting and future steps in order to solve this.

Today, I inspected from Clutch Reservoir down to pedal assembly. Found nothing broken, loose or leaking.

I did a complete flush and bleed of Clutch fluid with RBF600. Got some air out, but negligible. Can't really say how I would have introduced air to begin with. That portion is eliminated.

Test drive produced same results. Engaging on a hill, is very difficult as I cannot feel clutch grabbing and I'm almost at top of pedal travel. Something I would have to get used to.

So the next easy, least expensive and intrusive step is to replace the pedal assy and MC with RJM kit. Is this logical? or is there anything else I can do without removing transmission?

and I am owing $2000 to ZSpeed for clutch kit. :stirthepot::p

Does the clutch feel like it's slipping?

Not really. Aside from high engagement point and throttle/clutch matching, I don't feel it slipping while in gear and accelerating.

If it is, it's very slight, and it felt like it did once, but it felt more like a throttle hesitation.

RJM+Tilton MC kit on order.

Update
 

In the process of removing bits and pieces to get Tranny out.

I decided to boroscope the clutch with transmission still attached.

I have proved my theory of bent Clutch housing/pressure plate springs.

I was going to comment a damaged pressure plate as soon as I read the crank pulley story.

I had a similar situation, folks seem to underestimate how tight these bolts can be.

I tried the starter way and blew my main fuse after 6 attempts, fire and lubricant

Being that my car is auto I even used P + ebrake + rear wheels on the floor and nothing

I had to take off the front and hit it with Bertha (heaviest duty 1/2 Impact)

It came off like a 10mm bolt(so upset)


Summary: the force inputted is not enough to damage the transmission regardless of how tight. For example if I would have kept going I would have destroyed the parking gear slot by using a gear.

All jokes aside it you can easily put 300+ lbtq of constant torque on this bolt when taking it off which doesnt seem like much but being that this is tuned bolt on torque numbers we know the stock clutch would likely die in a few pulls.

Maybe a stronger pressure plate would have done better but most likely would have ended the same. Sucks that you had to learn this way.

I'll get a better idea once everything comes out. I'll post more pics too.

I still don't see how that part of the diaphragm got bent just by you trying to loosen your crank pulley bolt?

With the car in gear and the clutch pedal up, the clutch disc is in contact with the flywheel which spins the input shaft of the trans, the drive shaft then the wheels. The tip of the input shaft sits in the pilot bushing. The input shaft has splines which goes through and aligns with the clutch disc.

The throw out bearing makes contact with the diaphragm. It goes over the input shaft. When you push the clutch in, the CSC pushes on the diaphragm to disengage the clutch disc.

Are we not getting all the deets? Or am I just not thinking enough of how this could have happened?

Yes coincidences happen. I've fixed cars for what it came in for and as the lot attendant goes to take the car to the drive, the check engine light comes on for something else and I'm labeled as a thief.

Highly possible that this was the final drop to a hurt pressure plate.

The most likely theory if it's not the previous one is that the clutch offered enough grab. You have to understand that the transmission was not giving in locking the entire drive train. You'd expect the clutch to give up however if the disc does catch and grab the drive train starts to put pressure forward since the wheels are trying to spin. This puts upwards and downwards pressures on the input and output shaft as well.

The more I keep explaining it starts to sound like this would really only happen on a hurt pressure plate, though possible that it has the ability to mess up a plate, if it's hurt (worn teeth) it will bend them

We'll know better once the stuff comes out. (someday)

My theory is with BULL. Clutch disk grabbed on the clutch housing. Wether it was on it's way out, who knows.

I had NO issues or hints of issues with clutch, prior to crank pulley removal.

Puzzling..yes. Coincidence...maybe. I'm not dreaming this.

My thoughts are that the friction disc being held in place by the trans being in gear and parking brake engaged put sufficient forces on the pressure plate when you started to turn the crank bolt counter clockwise to loosen it. This action was opposite of the normal direction and usual forces etc. that have always been applied to this original pressure plate and it was sufficient force to slightly deform it which is why the diaphragm fingers are no longer in alignment. This means that the friction disc does not fully disengage when depressing the pedal so it is hard to shift from one gear to the next or from neutral into a gear. Outhouse luck and most likely a rare occurrence. I feel for you and as you know you need a new clutch. Release bearing, pilot bushing (or bearing in Nismo) pressure plate and friction disc is what will probably be needed as you have probably figured out. Thanks for posting so others use a different method to loosen this difficult crankshaft bolt.

The best method is to hold flywheel through the Provided access panel, with the proper flywheel holding tool (or home made tool)

I understand what Dreadnaught is saying and 100% accurate. However, there was a slight turn of gear train before transmission held everything. Thats when I think I did it.

Again, to reiterate, this is only a theory at this point. I know I added some pictures and suggested i found the problem, but nothing is certain yet.

I'm hoping to have it off this weekend.

Thanks for your response. :tiphat:.

zz

The best way to do it in a tight space is to use a large chain wrench to hold the damper and a large 1/2in. pull bar. That's how I do them. When the space is tight and you can't get a 1/2in. impact on it, that's what you do.

That's how I've always done it as well. Speaking of ol' chain wrenchy, I haven't used him in a long time.

Anywho, I just don't see how this one diaphragm finger got bent forward. The CSC is in constant contact with the inner most part of the diaphragm per the witness marks. If the transmission was in gear with the emergency brake on while your turning the engine by hand and the tires are on the ground, I would expect the splines on the input shaft to get messed up since the clutch is wanting to spin when the input shaft isn't.

It's like when you use the correct size socket on a bolt and you start to round the bolt head off since the bolt is so tight.

And going back to the one diaphragm finger being bent forward still shouldn't be enough to disengage the clutch from the flywheel. In proper operation when the CSC pushes forward on the center of the diaphragm the outer part comes back allowing for another spring loaded piece that is behind the clutch disc to come back as well.

Night night, and post pics of the destruction. I'm curious what you find. And do the job on your back. It will be fun.

Also, in the pictures, what we are seeing is the overcenter fingers. Not sure what it does, but they are in correct position. I'll figure it out once it's out.

I am in process of removal. I have a quickjack and it's been a lifesaver. So far everything is coming off easy and in good order. No issues being on my back. ;)

Please feel free to add all your theories.

I do have the new Milwaukee 1/2" mid torque impact, and it looks like it would fit.! Says it can bust 650 lb.ft, even if it does 450, I might win. LOL. :rofl2:

Thats another story.

All my upgrade parts are in. New Oem clutch assy. new OEM
CSC slave new OEM master. New OEM Dual mass FW. Can't wait to try it out.

zz

Just joking about the OEM stuff. Zspeed and RJM stuff.

Anyway, tranny is out, clutch is out. Can't see any physical damage to anything there. Bolts were tight and wear looks normal.

The clutch disk springs are loose in their position. I can spin them with fingers. I think that is normal.

The flywheel, I can turn the dual pieces slightly. about 1/2" either way. Is this normal?

Pics to follow.

as promised.

It's all back in!. Just working on the RJM Pedal and Tilton MC install. Keep getting pulled away to other things. Now it's snowing and I plowed all morning.

Too tired to do anything.

Bling!

Did you install a new rear main seal and pilot bushing as well?

YEs and yes.