Kentetsu

Okay, the time has come. My clutch suddenly began to go weak on me after a weekend of showing off over at the big annual car show in Detroit. So many rotary fans, so many requests for burnouts, so hard to say no to the girls when they take their shirts off.

So when it came time to decide on a replacement clutch, (since I am no expert in this matter) I got in contact with Jeff20b. I figured why try to learn everything about clutches when we've already got a resident expert. In exchange for his advice, he asked that I do a writeup on the procedure of replacing the clutch. So here we are....

I decided to go with an Exedy kit (#10806). Billy from Respeed was able to locate one for me and got it to me in his usual fast-as-lightning manner (thanks Billy!). The kit looks good, and came complete with the throwout bearing, pilot bearing, clutch alignement tool, and another bearing I haven't figured out yet. The pilot bearing is currently residing in the freezer in preparation for the installation.

So, after spending Sunday afternoon cleaning all my wife's crap out of my garage, and arranging my tools and stuff, I was finall able to move the car inside. I think I also removed the hood and drained the radiator that day. Overall, not a bad start for not really trying very hard.

Day two, began disconnecting all the miscellaneous bits and pieces (wires, hoses, cables, etc.). This was the simple part, because over the years I've stripped out about everything that is not absolutely necessary, so there isn't a whole lot to remove. I also made a number of modifications with a quick motor change in mind the last time I had the motor out, like quick disconnects on some of the wiring, and a few other small details that really made a difference.

Day three (keep in mind, I can only work on the car for about an hour each day due to work and family obligations). Got underneath the car and disconnected the drive shaft, wires to the starter and tranny, and removed the tranny cross member. That was another area where previous modifications made a big difference. Having previously cut an area out of the heat shield where the catalytic converter would have gone, getting to that passenger side bolt was easily accomplished (no need to remove the heat shield, or mess with frozen/rusted bolts associated with such). Then, inside to remove the shift lever assembly.

Anyway, here are a few pics (in the last photo, you can also see my dual fuel filters):

Kentetsu

Here are a few more pics of the engine removal process, just for those who may not have had the pleasure of performing this operations themselves.

Kentetsu

Kinda like watching a live birth, ain't it?

I also added a photo of the instruction sheet, which details a common cause of damage while installing a clutch. They warn you not to allow the weight of the tranny to sit on just the splines of the clutch, otherwise it can bend the clutch. I remember that it can sometimes be difficult to get the tranny mated up to the motor, and I can easily imagine doing exactly what they warn against. Good info to have, so I thought I'd throw it in here...

Kentetsu

And now, on to the diagnosis of this failure:

Hopefully Jeff will be stopping by to give me some input on this failed clutch. I can see some discoloration on the flywheel and pressure plate surfaces, which I believe comes from the clutch slipping and building up heat.

What is kind of weird though, is this feathering on the edges of the clutch disc.

Kentetsu

Okay, I made a closer examination of the clutch disc and may have answered my own questions. Although it is difficult to see in the photos, one side of the disc is worn down to the rivets. The other side still has plenty of material left.

Is it normal for the disc to wear more on one side than on the other? Or are they built in an uneven manner for some reason? Either way, one side looks good while the other is shot. Fortunately for me, the side that is shot is the side that faces the pressure plate (so no damage to my flywheel).

So, I'm going to get back to work now. Wish me luck.

Edit: Scratch that. Closer inspection of my close inspection revealed that it is worn down to the rivets on both sides of the disc. It was simply disguised by gunk. So I guess that the reason for failure was that it was just plain worn out.

Stevan

iTrader: (17)

I have always wondered if it was the pressure plate springs getting weak, in combination with all the friction surfaces getting glazed over(and of course the disc wearing out). I kind of doubted the springs weakening, and wanted to try just sanding the glaze off the pressure plate and reinstalling it with a new disc (also getting the flywheel turned, or sanding it as well). I'm too lazy to go through all that work to find out.

Stevan

iTrader: (17)

That's interesting, I recently bought a used aluminum flywheel, and the friction surface is worn unevenly also. It's easy to tell because it's worn down to the mounting bolts. I'm now thinking that it would be difficult to tell on a steel flywheel. I guess that's why it's recomended that the flywheel is turned. So much for the ghetto sanding method.

Kentetsu

Yeah, I took a closer look at my flywheel surface, and it is showing it's miles and wear. I'm going to check pricing on having it resurfaced. I've already got the car torn apart, so this is no time to start taking shortcuts I guess...

80's old school

iTrader: (7)

First off WTF??? Why did you pull the engine?? I hope NOT just to change the clutch....
Anyhoo....good luck with the replacement...

All my years of owning clutch cars...good advice is to change the clutch at the first sign of slipping. Sure saves having to regrind/replace the flywheel.

BTW Kentetsu....3days?? I just did this job in 3 hours suffering from the worst whiskey induced hangover ever!!!

Jeff20B

iTrader: (13)

That looks like an HD disc, and it looks like it failed in the usual manner. It gets thin, then it slips. Is that a street strip pressure plate? The rivits look like it. I hope your new setup feels better to drive.

That extra bearing seems to be included in most new clutch kits these days. No idea why.

Kentetsu

lol, read closely. Three days, at 1 hour per day = 3 hours

And yes, I pulled the motor to replace the clutch. I do not like working underneath the vehicle any more than I need to. Plus, you ever try to pull a flywheel off with the motor in the car? Might be a different story if I had access to a lift, but with nothing but jackstands (and since I own a hoist) pulling the motor/tranny as a combo made sense.

Kentetsu

Yep, that's the street/strip PP.

Question for you; I have read a bit on replacing the pilot bearing, and there was mention of a pilot bearing seal. I do not have a seal, I do not see a seal installed with the current bearing, and Autozone has never heard of a pilot bearing seal. Is this simply a matter of the propogation of bad information? Do these seals actually exist?

Jeff20B

iTrader: (13)

Bad information. I've seen several engines where the pilot bearing was not installed deep enough, and was missing the seal. Or it has the seal, but it's still not deep enough and smashes into the shaft where it expands to the splined part. There was even one from University Mazda (the first dealer in the US I think, so they should have got it right but failed) and the pilot bearing was so far rearward that it broke and the inner race was rubbing a nasty gouge around the input shaft where it goes up at a 45° to the spline section. The needle bearings had been ground down to a fine dust. Disturbing. Yep screwups on the pilot bearing are unfortunately pretty common.

You are supposed to tap in the pilot bearing until it bottoms out. Then tap in the seal. Then fill with a correct amount of grease. Ever seens a pilot bearing filled to the rim with grease? Yeah, that's good for a clutch disc. A lot of stupids out there, and we pay them to work on our cars. Scary. Nobody touches my cars but me.

I'd post a picture of a pilot seal but the Mazdatrix website is down.

I have three questions for you. Is your pilot bearing bad? Is the seal bad? Was it behaving improperly before you pulled everything? If not, leave them alone. It's far easier to reuse a known working pilot bearing than to have a clutch job take days and weeks (months) because of a simple pilot bearing swap gone bad. I bet your motor will pop before the pilot fails.

I see a beehive. Got the leak of death yet? You rerouted the heater core hose to it; not sure whether that's a good move or not. I just remove the restrictor in the pipe that runs along the side of the frame rail and up to the heater core. Keeps oil temps lower it seems.

Kentetsu

Well, I already started attempting to remove the pilot bearing, so its pretty f'd up. I remembered afterward that I read somewhere that it was advisable to reuse the bearing if it wasn't causing issues (which it wasn't). Dumbass move on my part.

I rented a pilot bearing removal tool from Autozone, but of course the jaws are too big to fit inside the bearing. Anything else would be too damned simple I guess. I think I'll just modify the bitch so it fits right, shouldn't affect functionality for the other uses it sees.

So, looks like I'll have to track down a pilot bearing seal then. Doesn't appear to have one now, but if it's supposed to be there then so be it.

Beehive: I fixed the leak of death shortly after I bought the car. In fact, I believe that was the issue that brought me to this forum in the first place. I have a front mount, but it needs to have the bung(s) welded due to a crack, and I still need lines for it. Not in too big of a hurry to do that though, since my temps run real nice as is.

Still not sure about the flywheel, and whether or not I should have it resurfaced. It feels a little "ripply", kinda like a slightly used brake rotor, but I've never had engagement issues or anything. I'm thinking I'll do it just to be on the safe side, so my new clutch doesn't wear out prematurely or something, but I'll have to check on the cost and turn around time.

thanks for the input Jeff.

bwaits

iTrader: (12)

Good job on the write up so far. Three points: First, certainly resurface the fly wheel if it is "rippled" or "Blue" spotted. You may toast the new clutch disk if you don't. Second, make sure to pick up a new pilot bearing seal even if you do not replace the pilot bearing. They do not come with clutch kits (not sure why) and that is why you see so many cars without them. Third, make sure to get everyone pictures of the two special bolts with the shoulders that bolt the pressure plate to the flywheel - when you get that far.

-billy

orion84gsl

iTrader: (5)

Ah yes, those stupid doweled bolts. They only go in two of the six holes on the flywheel, and not remembering which holes they go in can add precious minutes to an already aggravating job. The trick I used was to pull them, then after removing the PP, put them back in their proper holes. Made it a hell of a lot less frustrating.

It also makes sense to pull the engine and trans if possible. It's not that hard, your fluids could probably use a changing anyway, and it makes it a lot easier than lying on your back under the car trying to lift a trans back in place.

I currently don't have a throwout bearing in. I replaced my clutch just after DGRR09 with a stock replacement, which promptly grenaded 4 months later at an autocross. The new pilot bearing came out in pieces and I was using my friends driveway to swap in a better clutch, so I couldn't run out and get a new one. I don't think it was seated properly. Not entirely sure though. I'll be pulling the engine for a rebuild in the spring, so I'll have another look and have whomever I choose to rebuild the engine put in a new pilot properly.

You car looks so silly when it's not sitting 4 inches off the ground.

rxtasy3

iTrader: (2)

if u look into the bolt holes u can see which holes those shoulder bolts go in. those holes have the thread that start farther down into the hole. that shoulder on the bolt aid in the alignment of the pp for the flywheels that don't have the alignment pins.

Kentetsu

Thanks for the tip on those bolts. I was not aware of that, well, not yet anyway.

I'll get some photos of them. I'll also find a pilot bearing seal, and get the flywheel resurfaced. No sense in doing it if you aren't going to do it right, eh?

7aull

iTrader: (2)

I heard a rumor that its better to use the throw-out bearing from the turbo engine because its heavier duty construction....
any truth to this?

Thanks for posting your project Kentetsu - have a clutch project in my future so this is GOLD.
Stu Aull
80GS
Alaska

Kentetsu

Man, did I ever mention how much I HATE working on cars???

Finally got the @$%!@% flywheel off, and the pilot bearing out. But what a cluster that was. Had to use the dremel to get the pilot bearing out, and when I went to put on the attachment I wanted to use, the damn dremel broke. Spent the next half hour repairing that.

And I'm sure that most of you are aware of how tough it is to get that blasted nut off the flywheel. What is it, like 800,000 foot pounds that thing is torqued on with? But of course, when we installed this motor we did it right, which means using lock tite on that nut. Bent a 4 foot prybar into a horseshoe shape, but that nut finally let loose.

When the nut broke free, the 6 foot pipe I was using on the breaker bar fell right on my foot. Not the healthy foot, of course, but the broken foot, which made me see stars. Time to break out the codein and call it a day. Well, after I do some online searching for a pilot bearing seal, and a rear main seal (since I'm that far into this, might as well). And I have to return that useless pilot bearing removal tool and slide hammer to Autozone, so I'll see if they resurface flywheels to. Then that's it for today.

Hell of a way to spend my 41st birthday. But at least I've got a little sports car to work on. Could be stuck working on my dad's '82 chevette or something instead (again). So that's the end of my rant, and I'll stop my complaining now. At least I made some progress....

80's old school

iTrader: (7)

Good luck...at least your not hungover working on it! I now understand why you pulled the engine. I never have had to resurface a flywheel... Prolly a major PITA if the engine was still in the car....

Kentetsu

I tried to pull a tranny without the motor once, on an '83 Datsun Maxima (5 speed).
Ended up with the tranny laying on my chest with me pinned under the car struggling to breathe. Not fun.

Pulling everything as a unit makes it a lot simpler, then you're working out in the open, rather than under the car. I'm too old for that crap anymore. lol.

KansasCityREPU

iTrader: (9)

I take my engines to the big rig repair shop across the street the get the flywheel nut off. They have a 1" impact wrench. he's a good guy and doesn't charge me anything. Only take him a few seconds. A few taps with a rubber mallet and the flywheel brakes loose. A tip for those that haven't taken the flywheel off before. Once the nut is loosened, leave it on a few threads so that when the flywheel brakes looks from tapping, it doesn't fall on your foot.

Jeff20B

iTrader: (13)

Wow, you're having all kinds of fun.

Just fyi I never use locktight on the flywheel nut. Never had one come off accidentally yet. Just a light smearing of RTV (the RTV acts like a low speed lubricant for the nut and prevents oil seepage from the eccentric shaft). I just buzz it on there until it is correctly torqued. I guess you gotta do several before you develope a feel. It also helps to take off a few factory installed nuts like on automatics (because you'd be hard pressed to find a factory installed one on a flywheel since it likely has come off for resurfacing at one point, but auto counterweights are usually factory installed) and compare the length of time impacting with ones you previously tightened to the factory installed ones. Experience is the word.

I've never had a problem removing a flywheel nut except one which someone had used locktight. Man that sucked. I got it off though.

So don't use locktight.

Here is some food for thought. Did you know the engine rotation direction keeps the flywheel nut on? It also keeps the pressure plate bolts on. Kinda like how bike pedals have one with reverse threads. Or the REPU and some other vehicles have left-hand threads on one side. Same idea. Don't use locktight! lol

Kentetsu

Thanks Jeff, RTV it is...