zecc81

I bought the car with a chattering/shuddering clutch and took it to a generic place to get a new clutch installed. From then on every 6 months the car re-develops the chattering. So far I've been through 3 clutches (all covered on the initial warranty from the first clutch) and it's getting very frustrating!

Here's what happens:

Install new clutch - problem is totally gone for about 6 months

Eventually I start to feel very mild shudders as I pull away.

Slowly the problem gets worse until the car is very difficult to drive in traffic and for hillstarts.

Install new clutch - you see where this is going...

* Chattering/shuddering only occurs when pulling away in 1st and the car has been driven for at least 20 minutes (and clutch is warm)


So finally I've decided to get another opinion and this new guy says the flywheel, pressure plate, and clutch appear to be just fine, but the clutches this other shop has been putting in are cheap, generic Chinese no-name-brand clutches, and could be getting "hot-spots" much more quickly than a good clutch. He's advising to put in an expensive clutch, saying the quality will be much better and not develop hot-spots within 6 months.

Agree/Disagree? Other opinions/recommendations?

jackhild59

iTrader: (7)

Get an opinion from an honest friend about your clutch release throttle technique before you pay for another clutch. Don't take offense at this suggestion, but the evidence you described points to operator abuse.

duo2999

iTrader: (1)

how is your flywheel's surface?

zecc81

I understand, I'm not new to manual transmissions and try not to ride the clutch but I do do a lot of stop-and-go driving. I'm definitely not doing any clutch dumps or anything like that. I've driven with other people and seen other people drive their stick car and mine and I'm not noticing any huge differences. 6 months just seems a little ridiculous for a properly installed clutch to go out.

It was resurfaced, so it should be near perfect. The new mechanic also says it looks perfect. It'll be tested before the new clutch goes in though.

turboIIrotary

iTrader: (9)

What kind of clutch? Stock replacement? I test drove a subaru with a ebay xtd clutch and I could barely get it rolling without it chattering. I have been driving a manual for 7 years so i'm sure it wasn't my driving.

zecc81

They have been "comparable to stock" no-name replacements so far, but the new shop (a legit racing shop) recommends upgrading to a high performance clutch that will hardly get hot in normal driving and bite much harder. It's a little expensive but I don't want to go through a forth clutch, it's getting a little old.

I'm going with the "get what you pay for" logic right now.

RXSpeed16

iTrader: (41)

RotaryRocket88 did some interesting troubleshooting about warm clutch chatter recently. It ended up being the clutch hydraulics. I believe I had the same issue with quality clutch components, but the car was sold before I got around to it.
https://www.rx7club.com/showthread.p...ghlight=clutch

zecc81

Mmmm very interesting. I will definitely look into it. My only thought is why does mine only start chattering after 6 months with a new clutch? If it was just a hydraulic issue, shouldn't the chattering be there even with a brand new clutch?

RXSpeed16

iTrader: (41)

Maybe a fresh bleed clears up some of the gunk? I never ended up fixing it. IIRC the FC flywheel is a bit quirky to resurface. Do a quick search or maybe someone can chime in about it. There are only so many components involved with clutch engagement but wanted to throw that out there. Good luck.

Babbs

Well I just replaced my clutch and pressure plate assembly without getting the flywheel machined (still in very good shape). I just came back from all-day track lapping and everything worked well. I read in some posts here that if the flywheel gets machined then the pressure plate assembly mounting flanges may need some material removed also. This seems to make some sense as the pressure plate clamping force may be less because of the increase in distance from the pressure plate face and the fyywheel face. I'm not sure but it might be something to consider.

Babbs

zecc81

Update:


With the new clutch installed (ACT clutch and pressure plate, professionally installed with flywheel re-machining), the chattering actually seems to be worse, which may sort of be a good thing because it tells me engine mounts are a much more likely cause.

But before I spend a bunch more money I figure I'll redo the clutch hydraulics in light of the suggested thread. So with a new master, slave, corksport braided line and a fresh bleed, the chattering seems to be unchanged but I have one issue, the corksport line seems to be leaking.

The leak appeared to be where the line meets the top of the slave so I unscrewed the line and put threadlock in there (and re-bled of course). Still leaked. Soon I realized the leak was coming from the part between the tightening nut and the metal sleeve that is at the end of the braided part. This has got to be a faulty line... or am I missing something? I'm pretty sure I'm going to have to return this thing which will be a pain because they're an online retailer.

So maybe the hydraulic's are still the problem, I just have to get a working line...
Has anyone else had issues with corksport products?


More to come

SpeedOfLife

iTrader: (16)

Corksport has a long standing good reputation on this board. You might contact them and inquire.

Is your car modified to make more power?

zecc81

I've heard good things about corksport too, little disappointing this happened. And nope, all stock 86 NA.

zecc81

So I took the corksport line back and it actually was faulty. The new one works great and seems to have subsided a lot of the chatter from a dead stop, but it still does it in other situations.

It's livable right now but when it starts chattering it still shakes bad so I'm going to go ahead and do engine (and trans) mounts. I've been recommended mazdaspeed mounts, which are 35% stiffer, and I'm okay with a little more vibration, but 3rd gear has an fairly prevalent shake to it, at least that's what I feel in the shifter. Am I going to feel this in the car with stiffer mounts or does the transmission contain most of it?

Also there's quite a bit of clunking and knocking going on with the chatter (or when I push down the clutch quickly in 1st gear), what are the chances the metal crossmember that holds the trans mounts is worn out? (got the idea from here http://www.mazdatrix.com/g3.htm under "Rear Transmission Mount 86-92")

Furb

iTrader: (2)

Check the mounts before you just go out and replace them. There may be nothing wrong with them..

Grand Dad T11

Hi please remember I am English so if words are different cant help it
When you have decided that every thing ells is OK
And if you still think it is Clutch then I would suggest that you take the clutch and Flywheel to a Engineering shop and have the thick ness of the Flywheel checked
All so check the spines on the input shaft with the plate and see if there is any play in it should be a nice fit

zecc81

The engine and trans mounts ended up being pretty cracked (to be expected from 25 year old rubber, no matter the mileage) so they were ready to be replaced anyway.

And good news finally, the chattering is gone! There's still a little if I have to ride the clutch in reverse, but I hear that's normal. Overall a huge difference.

The only downside is the transmission, despite being recently rebuilt, made some bearing noise which is amplified quite a bit by the stiffer mounts.