Engine Speed Change with clutch depressed
 

Never had this happen before, when I installed the new motor I replaced the clutch with a "DYnaPAK" clutch (stock replacement). It is grabbing very well and feels like new. THe only issue now is that the engine speed drops when I let the clutch off while the car is in neutral.. ISn't that wierd? ANy ideas?

did you replace the throw out bearing at the same time???

Depending on the gear grease inside the trans, you can see some reduction in RPM's when the clutch pedal is released, as the trans bearings start turning and cause some resistance. You will notice more when trans cold as the grease is thicker/heavier, even if synthetic.

as stated above all thoes can be factors ... but i also thought it might be the fact that a pressure plate is on the friction disk causing more drag persay .. i could be totaly wrong asd i dont have full understand of the dynamics of the clutch system ..b ut it made sense at the time of thought lol

Is your clutch depression saftey switch still hooked up?

I have the exact same problem on my 86 DD and I haven't been able to track down the cause, however my safety switch has been TORN out of the car with zero wiring or anything left and I haven't been able to determine if that is related or not.

However I don't believe that its actually anything to do with the mechanical operation of the clutch, I put this one in with new everything - Ive done so on other 7's - and I don't have this issue. But that doesn't ENTIRELY rule out te mechanical aspect.

OK: couple questions.

1)Does it happen every time you come off the gas?, get an idle of about 1000, press the clutch - drop to 750
2)If it doesn't happen EVERY time (mine's about 6 out of 10) when it DOES happen,does the idle have a funny fluttering sound before you press in the clutch?
3)When you press clutch and the idle drops, is it a good solid idle? or rough/hunting?

Classic, I think I just figured out what my problem was... (BTW the idle drops when I let off the clutch) I replaced the throw out bearing when the clutch was replaced. BUT did forget to replace the gear oil after a bunch of it spilled out when the engine and tranny went out and came back in.. I bet that is causing the friction...

BTW none of the connectors are plugged up to the tranny right now.... if that answers your question.

hmm interesting.......

Actually now that I think of it......when I did the clutch o the TII (it had none of these issues after) I changed the tranny fluid after........but when I did the N/A one I just put an old yoke in the back of the tranny so I didn't lose fluid, never even topped it off once it was done.

Ill try some new gear oil and see what I get - nice work buddy!!

Heres the thing. I have the same problem on my '86 GXL. When you let off the clutch in neutral, the RPMs drop consistent with a load on the engine and I get a soft whirring noise that is loudest when the tranny is cold. After driving for a long time though it's alot more faint.

Classic you and I can help eachother out, I may just start PM you instead of posting..lol

same here

Seems like the "oil" in the tranny would thin out after a while of driving due to temperature, that would explain the faint sound.. But check your fluid see if there is enough. If so I would call the throwout bearing guilty.

hehe, yeah we've had some snyc'd problems lately - lol

Trans bearings.
The only part not turning when the clutch pedal is depressed is the transmission. When depressed, the throwout bearing is turning on the pp, the main drive is stopped and the pilot bearing is turning inside the flywheel, so if no noise those components are fine. When you let the pedal up, the clutch disc starts turning, which turns the main output shaft of the trans, which starts the gear moving. Have noise then, it's the trans.

ouch my autocross miata does that, I thought it was the throw out bearing...... Any quick backyard fix to quiet it down.?

Me too, I have the wirring problem too exactly the same

Bearing(s) need to be replaced.
Last weekend I listened to a RX8 with 33,000 miles. Fellow thought it was the t/o bearing, but everything was quiet when the pedal was down, indicating t/o & pilot brg ok. He would let the pedal up about 1" or maybe 2" and the trans started howling. In fact is was pretty loud as you could hear the noise maybe 10' away. He used RedLine, but looks like time for a rebuild. Sorry I don't know any easy fix once those bearings start making noise, other than replacement.

F$%K, im in the process to try to fix that noise, im replacing just about everything but the tranny. there is no noise when the clutch pedal is depressed, and when i engage the clutch is howls,. i also get a squeaking sound when i take off in first gear, is this a tranny problem> i hope not!

plz help

I changed my tranny oil. It made no difference, except it shifted a lil better for a while.

Also, when the tranny is cold, it makes a similar whirring sound in all gears but 5th where the overdrive drone is present. After driving for a while, again, it grows very faint.

But I also have a possible clutch problem. After long -ish drives. Intermittently when I take off, it seems like there's maybe oil on the clutch. It doesn't slip, but it vibrates/grinds in this weird way like the clutch can't fully grab.

2nd grinds for the first shift or two if it's cold outside .

3rd 'chirps' into the gate for two shifts if it's cold outside. Chirp as in it's very crisp, if you know what I mean.

I just wrecked the thing today, so it doesn't really matter for a week or so until Toyota fixes it. It was my fault on GA law technicality simply because I hit her. But, three cars in front of her slammed on their brakes, she slammed on hers, I mine. No ABS on the S4 whatsoever so all four of mine locked up. I tried ditching into the ditch, but you know how it is. If your brakes/tires don't want to cooperate there's nothing you can do. So I just let the steering wheel go to straighten out the front wheels and minimize the damage to be done to my car, and braced my grandmother. Yes, I did the 'Soccer Mom Grab'. :mad:

I herd that you have to wait for the Redline fluid to sink into the bearings for about 500ish miles before anything big happens. I also tried Redline plus the lucas synthetic stabalizer. Its a bit pricey, bout 16 bucks a quart. I put 2 parts redline 1 part lucas synthetic stablaizer. It seems to fix a lot of the hard shifting and some of the grinding but not the whinning.

Oh and by the way I have the same prob as you guys, almost identical.

I just did the clutch.I replaced the pilot and through-out bearings also.While I had the trans,comin off,I drained the oil from it,and replaced it with 80w90 Castrol(too cheap at the time to go synthetic)..The trans shifts smoother now since the clutch replacement,and the only Quibble i have is a little bearing noise with the Trans in nuetral.I'm confident that I did everything correctly and since the Bearings are new and i know that the fluids are topped up in both the Case and the upper reservoir to the shifter I guess I will call it normal bearing noise..Maybe I'm just too picky.The other things that I did also check were input shaft play on the transmission,which was minimal.Maybe the noises that some of the previous posters are experiencing could be related to "that" seeing that it was not mentioned.The input bearing and seal on the Trans by right should have been changed,and the tail bearing too?maybe.if there is one(not 100% with that) ..but I figure I'm the one that is driving the car,so if it boils down to anything related to those then I can Easily get to it since I'm familiar with the area now.. My .02 on it..maybe what my post is worth.

All RX-8s make that noise. It's the tranny main shaft riding on bearings--probably the very noisy roller bearings. Mine does it, and it is a common topic on the RX8Club forum. Not a problem.

Yea, that sound seems like its comming from the mid to rear part of the tranny, but more toward the rear... Interesting how this problem seems so common

This might help with some of the sounds you hear.

Transmission/Clutch Noise

Clutch pedal not pressed/neutral – Input shaft bearing
Fix: replace

Clutch pedal pressed half way – Throwout bearing
Fix: replace

Clutch pedal fully pressed – Pilot bearing
Fix: replace

In all gears regardless of clutch – Transmission gears
Fix: New transmission
Band-Aid: Better transmission fluid

1st gear whining – Input shaft bearing
Fix: Replace

Grinding when shifting – Bad synchros; shift fork; bad clutch system
Fix: Replace
Band-Aid: Better transmission fluid; shift slow

Notchy shifting – Bad synchros; bad bearings
Fix: Synchros - Rebuild transmission/buy a new one; Bearings – replace
Band-Aid: Better transmission fluid can help temporarily

Nice ^ good info...

Yeah, apparently my input shaft bearing is going :(. Why can't it be something easy to replace (relatively)...