Benjamin4456

Ok, it seems like I've always had some sort of clutch issue (even across multiple engines, transmissions, masters and slaves, etc...) although for now that's besides the point. As of lately I've noticed my clutch will engage at different points at random - this has probably happened for some time, although I've really been noticing it recently. Sometimes the pedal will be all the way at the top when it starts to catch and sometimes it will be more towards the middle. This clutch kit has less than 2000 miles on it just to note. There are also times where I can feel that nothing is happening in the top of the throw (where the master is being depressed, not the freeplay) but then other times I can feel resistance right away. It's really strange, and seemingly random. So far I haven't been able to guess what's going on and I won't have an opportunity to drop the trans for a while yet to investigate. It's also hard to drive a car with a clutch the likes to change its engagement point at random - hills particularly. I've also had issues with my clutch slipping on occasion for a while now.

Has anyone ever experienced something like this? I'm not losing fluid, the master and slave are new, as well as the clutch kit as mentioned before. The pedal also does not sink (or lose pressure as it can't really sink when depressed) and the clutch always fully disengages. The randomness is really what confuses me. I also have some rpm specific (and mostly in 4th) driveline vibrations that have occured since the transmission was last out, so that's slightly concerning. Theories?

rxtasy3

iTrader: (2)

the clutch master or slave cylinder may be letting fluid pass by the seals. if u lightly rest ur foot on the pedal, taking up the free play where u start to feel resistance, can u feel it slowly going down? look under the dash at the back side of the clutch master. does it look like it's been leaking?

mazdaverx713b

iTrader: (91)

My first thought is the clutch hydraulic system. How new are the slave cylinder, clutch hydraulic hose, and the clutch master cylinder? If there is no leakage that you can see on the firewall from the master or no leakage present in the boot on the slave cylinder, how old is the fluid in the hydraulic system?

Has the clutch pedal adjustment rod ever been messed with? You may want to check to make sure that the luck nuts are tight on the rod and adjust the pedal if it's out of spec.

GSLSEforme

Not much else besides clutch hydraulics that can cause different pedal feel and change clutch engagement position.
Likely fluid is dark in clutch master cylinder reservoir.

Replace clutch master and slave cyl. and flex hydraulic line between. OE flex hose ok,stainless braided hose gives smidge better feel.

Benjamin4456

Master is about a year old, slave and new line (stainless) were replaced in July. I haven't noticed any fluid leaking, and based on the fact that I haven't seen the level decrease at all I would assume it's tight. I'll check Sunday to be certain though - I'll check the pedal and linkage then too. Fluid was of course replace in July with the slave and hose. It's perhaps a little dark, but I believe that's just some residual old fluid from when the stock rubber line was causing it to turn black.

Is there anything that might be going on in the transmission? Perhaps something weird with the fork, I don't know... The hydraulics seems okay, but I will confirm that Sunday. I could also flush some fresh fluid through if y'all think that is warranted.

Thanks thus far.

GSLSEforme

What brand parts are you using?Dark fluid is sign of seals degrading.
If there was something wrong with the release mechanism inside bellhousing,you would have noticed it immediately and every time you disengaged/engaged clutch.
Only failing hydraulics cause inconsistent symptoms.

I learned a long time ago to replace those components in pairs,and use good quality parts. It is so common to have remaining part in system fail shortly afterward it’s not worth trying to save money. It is common for the worn,in service part to migrate crap from it to other parts in system.
There’s a lot of cheap Chinese junk out there works for awhile then takes a crap. The dark fluid is a clue
Fact that system is not low on fluid is another clue.
One of the cylinders is bypassing fluid from a compromised seal. Dark fluid in master reservoir means probably the culprit. You shouldn’t see dark fluid in clutch master reservoir til it’s at least several years old and never if you change fluids periodically.

GSLSEforme

The clutch pedal can sink to the floor while you have it pressed down,symptom there is car begins to move as pressure bleeds off while pedal is depressed and clutch begins to engage.Possible engine will stall.

Re vibration,did you check for a separated trans mount while it was out. Very common for them to be separated and also often this leads to driveline vibrations. While you’re checking that make sure driveshaft hardware is tight and put hands on u joints to see if they’re loose. Sometimes removing driveshaft is only way to check u joints in all four positions to check for tightness/binding.

Maxwedge

iTrader: (1)

Mazdatrix's gives different part #'s for Clutches and Slaves between the '84-85 12A and 13B cars. But both cars use the same Tranny and pedal assembly right? What's different in the cylinders? I want to replace these now, with my 12A still in. But I have a 13B on the stand going in next summer. Will the 13B parts work for either?

Sorry Ben - not trying to hijack thread. All out top minds are here already, so..

Benjamin4456

Not certain the brand of the master (I will check when I have a chance) but the slave and hose are from Mazdatrix, so whatever brand they use; oem slave probably?

As for the fluid, it has not changed in color from the time I installed the new hose and slave. The current color is due to what little residual fluid there is from before.

The pedal does not sink to the floor, or get easier to depress over time (as in it seems the system is not losing pressure due to a leak). I can hold the pedal down as long as I want in gear, and the car will never begin to stall.

Trans mount was replaced within the last four months with a 'competition' mount. I expected vibration to increase after the change, and it did, but since then I've dropped the trans to replace the pilot bearing and after doing that the vibrations got worse than before. The clutch was also replaced in July, so essentially all clutch related components are low mileage. I've tried rotating the driveshaft to see if it was orientated wrong but it didn't change a thing.

Driveshaft hardware is tight - checked it again after driving around a while after the transmission work. No change in vibration since the transmission going it. U-joints a bit worn, but they aren't binding and aren't terribly loose either. I do have a lot of driveline slop, but it's mostly coming from the spider gears in the differential (checked that a few months ago). They aren't broken or chipped, just sloppy.

Benjamin4456

Haha, don't worry about it. I don't have any experience with the 13B trans or engine but for the 12A I think all that changed was the bleeder and hose inlet locations. Don't quote me on that though, I'm just wondering if it might be the same deal for the 13B setup. I've used both an 80 and an 82 slave/master combo on my car with no issues, but the 83+ one does look a bit different. Maybe they changed the bore size, who knows... really just speculating here.

Worst case you buy the 13B slave and find out it doesn't fit and buy a 12A one to use temporarily. I'm sure the "top minds" will chime in sometime here .

Edit: I seem to be having issues with notifications and latest posts showing up, so if one of my replies seems out of place or something, that's why.

Benjamin4456

Ok, time to revive this thread.

I finally got a new master from Mazdatrix and... the problem didn't change at all. So now, I have replaced every part in the hydraulic system relatively recently, aside from the hard line, and none have changed my issue. Just to restate the situation, it would seem as though somehow my clutch system is not returning fully, because quite often the clutch only begins to have pressure halfway down (the point itself changes somewhat) the pedal travel. I don't have any issues with shifting gears or the clutch 'going to the floor', although when my clutch is acting in this weird way, there is a much higher tendency for my clutch to slip under hard acceleration. This all happens seemingly at random and there are no leaks to be found.

As for replacing the master just a couple days ago, I do not know yet whether my fluid will change color, but the fluid in the old master was black. I flushed all the old out of the system, and so we'll see what comes of this newest change.

I'm beginning to wonder if it could possibly be something to do with the hardline. It was one of the first things replaced when I got the car about three years ago, and the parts store didn't have a short enough one in stock so I just made a coil to get what they had to the right length. That means one, it's much longer than needed, and two, perhaps the coil is causing some sort of bizarre air trap. Lastly, it could also be internally damaged, and perhaps clogging at random preventing fluid from returning to the master, just a thought. Otherwise I would think it could only be the clutch assembly or something in that area, although I have no clue how that would do it. I doubt a throwout bearing could be sticky enough as to prevent the clutch from returning all the way.

If anyone has some more ideas, please throw them on out here. It's becoming quite annoying to half the time not be able to accelerate quickly, and then the few times it does, being unprepared for it. The transmission will be getting swapped out within a month (hopefully), so I will have access to the clutch assembly area to inspect things in the nearish future.

t_g_farrell

iTrader: (1)

Maybe a throwout bearing is sticking and not retracting with the fork when the clutch is reengaged. That would explain slippage and pedal travel changes. I don't know, I think you may need to pull the tranny to resolve the mystery or live with it until it fails better!

KansasCityREPU

iTrader: (9)

Isn't there also a return spring on the clutch pedal?

Benjamin4456

It very well might be the throwout bearing, I'll have to find out. Like I mentioned, I'll be swapping transmissions fairly soon for a couple reasons. Mainly it's that both of the two transmissions I've used/am using were in poor condition to start with and only got worse, and second, to replace the pilot bearing for the fourth time in a year (it's a long story). Anyway, when I picked up the parts for that I also got another throwout bearing and a couple other small parts, so it looks like that was a good idea at the time - particularly if the throwout bearing has been staying constantly engaged...

As for a pedal return spring, yes there is one. It seems to be working fine though, and when replacing the master I finally readjusted the clutch pedal 'free play' so I don't have so much slack any more (which would indicate that it is working, because otherwise it would have been sitting on the piston linkage and no higher). Regardless, it seems to be working fine but thanks for the idea.

DummyFixer

I assume that you have bled the clutch system. but even so, that coil could have a big bubble in it.

Benjamin4456

Yeah, each time I've done clutch hydraulics work I've bled it to the best of my ability. I think I'll replace the hardline anyway since it just isn't 'right'. The coil faces downward, so in theory it wouldn't trap air, but who knows. I can likely do that sometime in the next week or so.

LongDuck

I just read all that and thought I'd throw in some commentary that might stick in your head with everyone else's troubleshooting tips. Here goes, and in order from your foot to the clutch plate;

1) Master Cylinder - You say you put a new one in, but even new parts can be faulty. If you check the inside of the firewall, feel under the Clutch Master for hydraulic fluid leaking down the carpet. If this is the case, you're losing your hydraulic pressure due to a bad piston seal at the back of the piston, and where it leaks fluid - it leaks pressure. Bench bleeding a new Master Cylinder is as much to purge air from the system as to be sure the seals work correctly before you kill yourself putting it in the car, only to find out then that it's bad...

2) Hard Line - Your funky hard line sitch is a confounding variable. If you want to remove that variable, get an OEM hard line and be done with it. Retrofitting other parts to work in place of factory designed and tested components rarely works out like you expect. NOBODY with an OEM hard line has ever had it fail - not that I've heard of, anyway. It will have the correct flare dimensions and internal volume, and remove this component from your testing.

3) Flex Line - I went with a stainless braided flex line and never looked back. They're worth the $$$ (and only marginally more than stock) and being teflon tube with stainless braid over the top, it should last the life of the car. Factory rubber flex lines allow expansion under pressure and give a mushy clutch feel, but that's a feeling that most drivers don't know because they've never had a stiff clutch linkage.

4) Slave Cylinder - Both Master & Slave should be replaced at the same time; if one is bad, the other is sure to follow. Fluid leaks into the rubber boot and may not be visible on the outside until it starts to leak onto the trans bell housing. Squeeze the rubber boot and you may find it's full of black fluid. That fluid is black because the black dust it contains is what's left of your piston seal.

5) Clutch Actuating Fork & Pivot Ball - I've never seen a Fork with a broken spring allowing it to slide off of the Pivot Ball, but feasibly it could happen. There's very little to go wrong with a Fork unless one of the tabs which touch the Throw Out Bearing broke off, or it's rusted to pieces, but I suppose it could happen. You can only inspect these parts by dropping the trans. A new Pivot Ball comes with the trans Front Cover, which should be checked for wear caused by the T/O Bearing sliding back and forth on it. Never hurts to replace it, and if you do that, might as well replace the trans Front Main Bearing and Front Cover Gasket (metal shim).

6) Throw Out Bearing - (disregarding the clutch because that seems to work intermittently, and they don't fail that way...) the T/O Bearing makes a lot of noise when it fails - grinding noises like rocks getting thrown around inside the engine. These can run hot and lose their grease, but even if it seized, it would probably still disengage and engage the clutch consistently. Likely is not the problem.

(*c'mon - you KNEW there would be 7 items!)

7) Pilot Bearing & Seal - You said you replaced this 4 times in the past year... That's very strange. Tell us more about that,

Benjamin4456

Ah, thanks for that comprehensive list. And yes, of course there has to be 7 items, of course...

1) I'll check the master again, but the old one wasn't leaking and it acted the exact same way. I also didn't notice any fluid when I was down there adjusting the linkage after bleeding it, but who knows. I'll check it again next chance I get.

2) The hardline is indeed a bit suspect. It was originally replaced because the parts stores around here didn't have anything M10x1.25 for the SA lines and I had an FB parts car I could steal clutch components from. That ended up with me buying the shortest M10x1.0 hardline our local shop had and then using the master, slave, and soft line out of my '82 parts car. I now have a roll of line from doing my brakes, so I'll probably just go pick up some ends and make one myself - unless there's some reason to not do that (I mean my brakes still work so...).

3) When I replaced the slave not too long ago I also got the stainless soft line from Mazdatrix. As of now I am running a new 1982 master, slave, and braided stainless soft line, all from Mazdatrix (so I believe the master and slave are Exedy brand, same as my clutch). Infact, all my soft lines are now stainless, although that's just talking hydraulics in general, not clutch specific.

4) Like I just mentioned, the slave was replaced recently along with the soft line. It and the master were not the same age, however, and so I figured that my newer master (which I replaced as one of the first things when I was trying to get the car running; after trying the one from the parts car) was due for an updated slave to pair with. Unfortunately, if there was a hydraulic issue, that may mean whatever junk was in one transfered to the other, although I can hope that's not the case. As far as I know neither the old or new slave were leaking (at that point I was replacing it trying to narrow down the possible causes for this issue). I can check again, but I'm fairly certain it is not leaking.

Just a general note in terms of leaks: Over the course of this all, I have never seen the fluid level go down in the master between changes. I have also never had an issue with the system losing pressure and then causing me to either not be able to shift or stall at a stop. The only problem that seems to exist is with fluid or some other part returning fully. This is part of why it's got me so confused.

5) I don't know enough to comment on this, but I will say that of course that will all change with the new transmission. So I suppose if that fixes it, further investigation on the old one will be required. I will still inspect the old/current transmission when it comes down regardless though.

6) Not a ton of noise from the throwout bearing (I would assume), although my transmission make a lot of noise anyway, so it might be. No rocks getting thrown around though, so my bets are not on it - unless perhaps it's sticking rather than broken, although I don't know how that would happen without something also being up with the fork. We'll have to find out.

7) Ok, I should have expected a request to explain this, so here we go. Technically it is the third time I will be changing the pilot bearing on this engine. The first time was on my previous engine which was then replaced this past June with my current engine. On the current engine, the first replacement was during the rebuild as I was also installing a new clutch to go with the '82 flywheel. Unfortunately I was at a friends shop doing the work, and I had left my bearing grease at home and he had just moved in so he didn't have any either. This ended up with a couple friends and I saying "eh, throw some assembly lube in there, it'll be fine". Well it wasn't fine, go figure... First off we put in too much and hydraulically locked ourselves from installing the transmission, but we didn't realize that. So we kept going late at night and finally just shoved it on there (we weren't in our right minds at the time) apparently damaging the bearing in the process. Next day we get the rest of the engine sorted out and fire it up, go through some first start stuff, and then decide to go for an easy test drive around the block. As soon as I put the clutch in there's this terrible noise and we knew immediately it was the pilot bearing. Over a couple days it 'improved' but it was still bad. Unfortunately, as this is my daily, I just had to deal with it and hope that it wasn't eating up my input shaft.

So then I finally get another pilot bearing. Drop the transmission, yatta yatta. Got the old one out and discovered that the inside of the e-shaft was caked in a black paste (no doubt the assembly lube). I cleaned that out very well, but then there were all these chunks missing in the hole for the pilot bearing I never noticed before. Based on the flywheel nut and now that, it seemed as though the PO must have really liked his chisel. Oh well. So I go to install the new one, but I didn't have the tool so out comes a socket. Somehow during installation I managed to slightly damage the bearing because when I tested it, I could feel a very slight catch every once in a while. After it's all back together I try it out, and while it's miles better than before, it still makes some noise and does to this day.

Finally that brings us to now, the third time it will be replaced (since June). This time around I bought the proper installation tool, and I'm crossing my fingers nothing else goes wrong this time. If all goes well after the transmission swap, maybe I'll have no bearing noise for the first time ever in this car - that would be nice. Anyway, that's the story behind the pilot bearing. Thanks for the checklist once again.

Maxwedge

iTrader: (1)

I can't get over you having an SA as your daily. Holy crap, your brave. In '88 my first car was a '62 Impala sedan, and that was OLD (26 years). Your car is 40 and having issues, and you daily it? I wish I was still young, dumb and full of..... clutch fluid.

t_g_farrell

iTrader: (1)

Bet you are getting good at swapping out the tranny! Maybe that pilot bearing is grabbing occasionally.

LongDuck

The Pilot Bearing disintegrating inside the end of the Eccentric Shaft wouldn't cause his clutch pedal to engage at different points at random, however.

I'm still thinking it's hydraulics - and likely one of your piston seals (Master or Slave) is bypassing hydraulic pressure at random. That's the only thing that could affect pedal travel as you've described.

The issue with the Pilot Bearing (and GREASE SEAL), may be compounded by the fact that the eccentric shaft is damaged from someone going at the bearing race with a chisel, along with having a few Pilot Bearings grenade themselves in there. In my experience, that black paste is actually the bearing rollers combined with whatever lube may have been on the bearing from the factory - it's a weird kind of paste, but I know what you're talking about.

Someone up there ^^^ said you may need for it to fail further to get to the bottom of this, and if you're not wanting to swap Master & Slave cylinders yet again - that may be where we stand.

Benjamin4456

Ok, we have some new discoveries.

First off, I checked over the master and slave (even removing the boot) and there is no fluid leakage. However, my fluid is once again dark. Now, perhaps that's because I didn't do as good of a job as I thought flushing out all the old, I'm really not sure. I sure hope it's not the slave's seals as it's nearly brand new.

That aside, I did a couple tests. First off, I must say that when driving the clutch changes how it feels seemingly at random, however, in the driveway today I was able to replicate the symptoms at will. First I tried the clutch with the engine off; it worked just fine and felt perfect. Next I started the engine and pumped the clutch and slowly the weird issue where there is little to no resistance until halfway down manifested. It stayed this way, feeling like there was no resistance until halfway down, the entire time the engine was running (for this test that is; as evident by my previous posts it changes at will while driving around). So I shut off the engine and pumped a few more times. What do you know, it felt completely normal again. Strange, eh?

So I got a friend to pump the pedal and told him to only pump (when the engine was on) to where he began to feel resistance, and then make a note of that point. Then I shut off the car and had him pump to the previously noted point (where the resistance started during the engine running tests). Guess what, the slave moved the same amount in both tests... And here's another thing that I forgot to mention before. When I depress the clutch to the point where resistance shows up (engine running) the idle raises considerably (perhaps 100-150rpm), but at that point the clutch is not yet disengaged. It's only after I fully depress the clutch that I can hear my damaged pilot bearing start to spin, telling me that the clutch and engine are no longer connected.

I hope that makes some sense. If I need to re-explain something let me know; I realize that might not have been too straight forward so let me summarize.

- engine off: clutch feels normal
- turn engine on: after a couple pumps the clutch does it's weird halfway bit
- turn engine back off: after a couple pumps the clutch feels normal again

- the slave moves the same distance regardless of if the clutch feels weird or not
- the idle raises when the clutch feels weird and it is depressed to the point where resistance begins (aka, where it starts to feel like a normal clutch again - about halfway down)

I've also noticed a very occasional grinding noise coming from the transmission when either idling in neutral or cruising slowly in parking lots. It's only happened three times that I recall, but it's only for a moment so I can't describe the situation too well. I'll pay more attention to this if it happens again.

At this point it sounds to me as though something in the transmission/bell housing is messed up. My biggest reason for this assumption is that the slave still moves the same distance compared between the clutch feeling normal and weird. I don't know that the deal is with my dark fluid, but when I replace the hardline I'll pull of the slave and have a look inside of it to see what's going on. I'll also flush/clean the flex line at the same time.

So, anyone have any theories? I'm honestly perplexed with as to what this could be. I won't have an opportunity to drop the transmission for a couple weeks yet (at least), so hopefully nothing goes south within that time. I don't want to rule out the hydraulics just yet, but it would seem to me (excluding the dark fluid) that they are working fine.

Thanks for the help thus far.

GSLSEforme

Just read your post and some of my prior responses. My 10 cents here...re: recurrent dark fluid in clutch master reservoir. There may be nothing wrong with your bleeding procedure. Only one thing can darken fluid in a closed system and that is is degradation of "rubber"sealing products in master/slave cyls.. There is a lot of poor quality chinese parts making their way into otherwise brand name parts. Brands i have had trouble with are Exedy,Centric,Beck Arnley. Don't even bother with any Dorman products,garbage.

I have reverted to what i did servicing these cars when i worked in dealership. I rebuild brake/clutch master and slave cylinders using Mazda rebuild kits.Disassembly,cleaning,honing. Yes,the kits cost more than replacing the parts with new that you would hope to be better when essentially you're bolting in future problems. Yes,it takes longer to achieve 100% quality control. My customers appreciate fix it right 1st time as do i. I hate having to stand behind a warranty on a substandard part. Same,same for brake calipers,starters. Did 1st clutch on my SE 8-9 years ago and though not leaking,rebuilt my clutch master and slaves with Mazda parts. I flush brake/clutch fluid every 2 years along with all driveline fluids. Fluid never darkens in either reservoir.
I use DOT 4 synthetic fluid in both brake/clutch hydraulics.

OP,i would also ditch your rubber flex line for new or ss flex version. Would also take hard line off,bend to approximate shape length and go to parts store and buy that length plus an inch or so in nickel/copper with flared fittings on each end and bend/cut to length and reflare the one end and install. Technically nothing"wrong" with that loop of hard line you have but eliminating it can only help.

RE: clutch release/engage weirdness. Aside from clutch hydraulics,the motion goes to mechanical at end of clutch fork and that includes the pressure plate,fork,pivot pin in bellhousing,throwout bearing support on front of transmission. All these are wear items,cars are old,they all need to be inspected closely. A worn t/o bearing support can have t/o bearing **** slightly in back and forth operation and the support collar being aluminum wears 1st. A leaky input shaft seal/gasket allows hypoid oil to seep out of input shaft onto collar and mixing with clutch dust makes an abrasive paste and excellent glue that can aggravate the consistent clutch apply/release height on pedal.
I have found more than once just remove/wiggle/install of trans is enough to aggravate a previously dry input shaft seal to begin to leak and my time is worth enough to me that part of a complete clutch job is to pull t/o bearing support collar and polish any marks if minimal. There will always be friction marks on them,polishing will determine if that's enough or replacement is in order. Replace input shaft seal and gasket. Good time to replace output shaft seal while box is out.

Clutch master cyl kit # GA02-49-520A
Clutch slave kit # FB01-49-460
T/O Support # 8540-16-220D
T/O support case gasket # 8540-16-225
Input shaft seal # 0603-16-103
Pivot pin # 0603-16-102B
Fork # 8540-16-520A

Benjamin4456

Cool, thank you for that info as well as those part numbers. It would be unfortunate if the parts I bought are indeed sporting poor quality seals, but I suppose that's why oem is usually such a great option.

As a small update, I have changed some plans and will now be swapping transmissions this weekend. Yesterday I got the 'new' transmission separated from its motor for the first time to inspect it - lots and lots of oil in the bellhousing. Good thing I picked up a new input shaft seal. Compared to my current transmission - if memory serves me correctly - this transmission has far less play in the input shaft (essentially none, whereas my current one has... more than ideal - probably why I sometimes get a vibration that feels like the clutch not being centered). Anyway, I'll be slowly cleaning it up over the next few days and getting it ready to swap tail housings for final installation into my SA. Assuming it's original to its donor car, it's a rather high mileage unit (200k miles), although it came from a fully stock vehicle that was seemingly well taken care of. The transmission has also been off before as there is a shop tag on the back of the engine indicating at least a flywheel resurfacing. Hopefully all goes well. I'll do a further in depth inspection later this week before I go to swap them, although so far all the gears are present/spin and nothing feels chunky so it at least 'works'. On a similar note, how much play is tolerable on the throwout bearing sleeve/guide? I haven't checked it yet, just curious for the time being.

GSLSEforme

Will caution you to get t/o bearing support to trans case gasket. You need to separate support from trans case to r&r input shaft seal. Odds are that paper gasket will tear/crack when you do so.

Amount of play for bearing on support subjective. Look for wear marks in area where bearing rides back and forth. Look at release fingers on pressure plate to be sure all are same height. Have seen bad wear patterns in t/o bearing support traced back to bad pressure plate causing t/o bearing to **** on support..

A light polishing will reveal low spots. Post pics if not sure.