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-   -   What did I break!!! (http://www.the370z.com/engine-drivetrain/138288-what-did-i-break.html)

ZoomZ 11-12-2022 07:15 PM

Quote:

Originally Posted by Rusty (Post 4032137)
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.

ZoomZ 11-30-2022 08:11 PM

Update
 
6 Attachment(s)
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.

THE BULL 12-01-2022 11:45 AM

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.

ZoomZ 12-01-2022 09:59 PM

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

Dreadnaught 12-02-2022 12:29 AM

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.

THE BULL 12-05-2022 11:27 AM

Quote:

Originally Posted by Dreadnaught (Post 4032775)
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

ZoomZ 12-06-2022 12:04 AM

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.

stansens 12-06-2022 02:47 PM

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.

ZoomZ 12-07-2022 11:48 AM

Quote:

Originally Posted by stansens (Post 4032888)
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

Spooler 12-07-2022 02:13 PM

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.

Dreadnaught 12-08-2022 01:22 AM

Quote:

Originally Posted by Spooler (Post 4032916)
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.

ZoomZ 12-08-2022 01:06 PM

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

ZoomZ 12-09-2022 06:01 PM

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.

ZoomZ 12-09-2022 06:08 PM

4 Attachment(s)
as promised.

ZoomZ 12-20-2022 04:12 PM

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.


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