First Time Clutch (and more!) Replacement Thread
 

Hi Folks,

I am creating this thread to ask all of my very basic questions about some planned work on my 83 GSL with ~35K on it. The reason to to do this is described in another thread, "Shuddering on Launch" https://www.rx7club.com/1st-generati...aunch-1128358/. That thread has a video of my problem and then diagnosis and recommendations from the experts on this forum.

To Do

• clutch assembly, throwout bearing, pilot bearing inspect/replace if nec.
• inspecting/refinishing the flywheel
• replacing the rear main engine oil seal
• input/output transmission seals
• new starter, as the existing one is increasingly missing engagement.
• checking u-joints on the drive shaft

Parts reference for others doing this in the future

• Clutch Kit is an OEM replacement, no performance aspirations: Exedy Kit 10025. This came with the pressure plate, friction disc, pilot bearing, alignment tool. Conspicuously missing is the pilot bearing seal. (Bearing insertion tool from Mazdatrix).
• Pilot bearing seal ordered separately, Beck Arnley 052-3471 Seal,
  Amazon
  Amazon
• Eccentric shaft rear main seal is Mazda part 1668-10-556A, https://www.atkinsrotary.com/store/6...8-10-556a.html
• Transmission seals front 0603-16-103, https://www.mazdatrix.com/getprice.a...m=16-1030-0603
• Transmission seal rear 0437-17-335A, https://www.mazdatrix.com/getprice.a...m=17-335A-0437
• Starter is a Bosch from RockAuto

Right out of the gate (pun intended)
 

So the first issue is, do I need to remove so much dash trim and this "middle rubber boot" and the shifter to drop the tranny? Read a lot of thread about the three 10mm bolts below this boot, but nothing explicitly described this mid boot, and interestingly most threads with pictures showed it ripped up, presumably for access. Not my plan!

It looks like I need to remove those bolts (5th is hidden below the trim's cross brace)...

https://cimg0.ibsrv.net/gimg/www.rx7...5e1ca7f95e.jpg

Stop...no need to disassemble interior any further. Reach down to the bottom of the top boot showing and put your fingers under the lip that holds it to 2nd boot underneath it and pull it away,turn it inside out and pull up around shifter shaft.
.
This will reveal 2nd boot which can be stretched and pushed down over shift tower on transmission which reveals the dust cover with the three 10mm head retainer bolts. Remove these bolts and pull shifter assembly straight out of top of trans.You will want to put down a rag or an old plastic trash bag to lay shifter assly on floor on passenger side to keep hypoid oil on shifter ball from leaking/staining carpet. Jam a balled up paper towel in opening of shift tower to keep dirt/rust from getting knocked into housing on trans remove/install.

When these cars were new(er) the rubber boots were much more pliable and friendly. After 30+years and lots of heat cycling,not so much. I have found way more cut/trimmed/ripped away than intact over the years.
They can with care be removed and reinstalled without damage and these boots intact make for a much quieter interior.

Some suggestions: 1st a heat gun/hair dryer is your friend. Used carefully it will soften rubber and make it pliable enough long enough to remove and to put back on at time of reassembly. The upper boot/2nd boot will likely be stuck together as one after being there for so long.
Heating will allow it to be peeled back and turned inside out. Sometimes a small pocket screwdriver or a like tool(not too sharp) needs to be inserted to start the separation process. This is where suggestion #3 comes in to play...silicone spray,with nozzle extension.
Once you have succeeded in separating a small section of upper boot from lower,hopefully without poking a hole in it,insert the nozzle and spray some lube around in there each side of screwdriver.

Suggestion #2 put a heavy towel across console area of dash before proceeding with #3 to protect dash and trim from scratches when screwdriver likely slips out of siliconed boot as you try to work it around to separate boot. Don't ask how i've come to this solution...

I believe Mazdatrix has pics on their website of replacement boots so you can visualize how they look separately. By now you see why so many cut/rip the boots on trans r&r,a lot of flat rate techs did this back in the day.

I always remove the four 10mm bolts and then slide both boots up and off of shifter. I do it this way to keep from damaging my boots any further because they are NLA. Then I can access the 3 bolts for the shifter to get it out of the tranny.

Either way can work.

Another thought. My preference is to repair what you have(regarding starter) versus any reman unit. The best quality starter is the original one now in your car. Within reason consider repairing. What is the symptom or symptoms that make you want to replace it?

Awesome, thanks you guys. I have all the time in the world for this, so I'm not gonna force anything. I had no idea that I was looking at 2 rubber parts! And for other interested parties, here are the photos from Mazdatrix:

https://cimg7.ibsrv.net/gimg/www.rx7...83291d3951.jpg
Top Boot

https://cimg3.ibsrv.net/gimg/www.rx7...a5bd4ac0a8.jpg
Mid Boot


The symptom is that when turning the key, there's occasionally no engagement with the ring gear, and the starter just spins. On the next or maybe one more attempt it will grab and start the car.

So I am removing exhaust and heat shields and I find this, sheesh:

https://cimg1.ibsrv.net/gimg/www.rx7...e36f78990e.jpg
Aftermarket transmission mount - a warning ;)

Glaringly missing one of the mounting bolt into the tranny case! And it didn't just fall out, the holes don't line up. Rock Auto part (see the excellent thread on engine mounts for more hijinx in that vein).

Now I'm glad I'm doing these jobs myself. For the "shudder on launch" problem, I am thinking this might be it...essentially it's half a transmission mount! I'm going to put in a new one and test drive it.

Edit: NEVERMIND! Jumped to a conclusion, it was fine all along.

Having to remove all the pieces to access the boot mounting bolts was always the deciding factor for me when doing clutch/trans work on customer vehicles. Always separated the boots as i described...as many cars as i did,the less pieces needing to be removed with inherent possibility of breaking something or misplacing something no matter how carefully you work was a factor when expedience and consistency was necessary. I was working flat rate. Of course i could have done like others and cut the boots out of the way,customer would never know...

Regarding starter symptoms,very likely cause is overrunning clutch worn out in starter drive. Your car even with low miles has had a lifetime of use with all the short trips and associated starts. Bosch electrical products for the most part are made well,is this a new starter?

While you have the transmission out,clean up the mounting surface for the starter motor on trans bellhousing til it is shiny. Likewise,clean the battery positive cable end lug and ground wire end lug til they are shiny copper. After all these years of oxidation there is always voltage drops present in these connections and even if your present starter was "good" after doing this and reassembling you would notice the starter audibly cranking over the engine faster on 1st start afterwards. Finish up your cleaning of cable ends with the application of vaseline with an acid brush as you are assembling the cables to the starter. You can use the same thing at the battery posts and terminals. The vaseline will "melt" and fill all the voids in connections. The connections will not corrode or oxidize as air/moisture cannot get to them.

Did you pay someone to install that?

Pro tip: When removing the clutch slave, remove it from the trans and you won't have to bleed the clutch.

Yes, not going back!

Damn,i rejected that as a cause for original complaint when you said the mount was new...properly installed correct mount can't help but minimize that,will it eliminate it? I will watch your thread to see response.
Same shop/tech put in those engine mounts you just replaced?

Ye, that's correct. I had him do the engine mounts, transmission mount, and a conversion form R12 to 134a. That's all though.

As you say, I'm not convinced this is the root problem...I'll probably still end up needing the clutch.

Super basic question on removing the exhaust system. I searched but no threads on properly removing FB exhaust. Maybe it's a dozen different ways that all work well? So I am thinking put a support under the cat, break at the downpipe, remove the relevant hangers, remove as an assembly. Here are the fasteners I was planning to remove:

https://cimg9.ibsrv.net/gimg/www.rx7...4d8392c571.jpg

Does this make sense?

When I do it I don't take the entire exhaust off. I put some rags between the top of the exhust tips and rear body panel so the panel doesn't get scratch/dented. I undo it from the exhaust manifold in pic 1 then remove the donuts in pic 3. This should be enough for the exhaust to be moved down to get at the trans cross member bolt on the exhaust side. Be careful of the heat shield. It's very sharp.

So I must be lucky, the 2 piece shift boot easily separated and the top is plenty pliable enough to work up and off the shifter. Here's what it looks like for the curious.
https://cimg5.ibsrv.net/gimg/www.rx7...af2ce9ebd2.jpg
https://cimg6.ibsrv.net/gimg/www.rx7...3f9cd79d7b.jpg

Be careful when you put your 3 bolts back in. Make sure the nylon upper bushing is aligned correctly with the notch and the steel alignment pin. I've seen some that were just put back together in any direction, crushing the bushing and it makes the shifter feel overly tight for some reason. Gee I wonder why.

Thanks Jeff, now that I've got it apart, I totally get what you're saying. For the curious, this is what it looks like after just coming out. Also the three 10mm bolts were not super tight, basically hand tightened, maybe a couple ft-lbs of torque to remove them.
https://cimg6.ibsrv.net/gimg/www.rx7...1c5825ee6f.jpg

--> Question: When reinserting, will I be aiming the ball to the left or the right of the retaining clip?

That bottom boot is thick and tenacious. I used a small flat blade screw driver to pull back the top edge, and then an empty bit driver to "roll" around the edge shifter's housing and push the boot's lip down and around, sort of like a mini tire machine
https://cimg6.ibsrv.net/gimg/www.rx7...2af719a47c.jpg


Still more fun! I am really enjoying this project. In the engine bay, I've got the slave cylinder detached and out of the way. Underneath, I've got the exhaust out, all of the relevant heat shields, drained the tranny, I marked and removed the drive shaft, and removed the starter. Which looks really, incredibly filthy. Something tells me it's a good idea I'm doing all of this.

Thick, oily grime spraying onto a starter looks like this:

https://cimg1.ibsrv.net/gimg/www.rx7...4c972ee351.jpg

And here's what awaits inside the bell housing. I'm thinking that some of the oil seals are not really sealed? This isn't typical, right?
https://cimg7.ibsrv.net/gimg/www.rx7...570021a82e.jpg


Gotta go over everything again, just to be sure, but I'm pretty sure the next step is to remove the transmission.

I have one of the harbor freight trans jacks, the small scissors one, love the 25% off coupon.

https://cimg8.ibsrv.net/gimg/www.rx7...c0bd663800.jpg

You'll want to clean up the ball on shifter and light amount of lube on that on reinstall. The spring is not a retainer it gives the shifter"preload" to return to middle neutral position as well as guide shifter smoothly through shift pattern. On reassembly install the ball to right side of spring.

3 shift tower bolts should be just snug,no need for gorilla tight. Basically keeping shifter cover flush to top of trans. Have seen more than a couple cars with only two bolts in shift tower,3rd snapped off in trans...

Some cars that 2nd boot has more "attitude" than others.

There's 30+ years of clutch dust in bellhousing,add some oil seepage,makes a nice glue. Pretty normal.That's why you have all seals on hand and one of reasons to remove flywheel. Wear a mask when you remove clutch assembly,washwipe down flywheel slightly once clutch/p plate are off to minimize clutch dust/chunks in your face. Once flywheel is off,inspect oilpan at back of engine to see if it's dry.
I use a 3'x4' aluminum hotel pan and situate trans in it so bell housing end sits in middle,wood block under tailshaft.
Remove t/o bearing,fork,boot and use brakleen,parts washer brush to clean out,rinse down bellhousing area of trans before removing t/o bearing support to clean replace seal and regasket and wipe/blow dry. Wash/dry flywheel and inspect,ship off to machine shop so that can be resurfaced while you do all other maintenance on trans and clean up parts.

Recommend using a block of wood between oilpan and centerlink to support engine in"position" while trans is out so no damage to ac,vacuum lines at firewall from engine tilting rearward. Also keeps strain off radiator/hoses,minimize collateral damage.

I always remove the big ring that holds the thick rubber boot. I also put some gear oil in the shifter box. When reinstalling the big rubber boot goes on last. This makes it easier to get the shifter and pretzel spring (my term) aligned.

I still think its easier to just pull that bottom boot off because reinstalling the shifter without removing it will be kind of a pain. Your choice.

That starter and bellhousing need a lot of cleaning. Buy stock in Brakeklean now!

LOL

I haven't had time to go at this since last Friday. It's all just sitting there taunting me. ;)

I think they all look like that! I'm in the exact same situation you are:
https://farm1.staticflickr.com/939/4...50850f51_z.jpg

Yummy.

lol

Progress. So I was a bit worried about pulling off the transmission on my own but not a problem. With the HF scissors jack tranny lift it was controllable and easily, incrementally movable. It took a bit or heft to pull off but other than that, smooth running. And the tranny itslef is a lot light that I thought it would be. Maybe overkill? supporting the rear of the engine with the factory scissors jack. Here's the set up.

https://cimg3.ibsrv.net/gimg/www.rx7...20a4970bc3.jpg

After getting it out from under the car I could get in to look at the old stuff clutch assembly. It's got fresh looking wet oil dripped down to the seam.

https://cimg2.ibsrv.net/gimg/www.rx7...549402cd14.jpg

Pilot bearing looks good...to me. The rest of the roller bearings look like these, none missing. See any issues?

https://cimg2.ibsrv.net/gimg/www.rx7...b9b23d5937.jpg


Next up, removing the old clutch assembly. Thanks for all of your help so far.

I'd say a little bit of grease applied to the needle bearings should be all it requires. The pilot seal looks ok. You could swap a new seal in but I'd leave the pilot bearing alone, just greasing it. Not too much.

I've done most of my clutch/trans jobs on a lift in standup position. Done lots on jack stands on my back with and without a trans jack. Being older now,much prefer the use of trans jack and you will too when you attempt lining up and reinstalling trans.
They aren't that heavy but the longer it takes to align input shaft/clutch/pilot bearing and get trans in place,the heavier it seems. That jack will be your friend...

Seen worse regarding dampness on back of engine,getting flywheel off and examining backside of engine/front of flywheel will tell what needs to be done.
Regarding pilot bearing,looks ok,bit dry,normal looking for low mile car...experience has taught me to replace regardless. In the past there were times i chose not to,couple came back with noise complaints,requires doing the job over again with no pay+unhappy customer.
IMO you have the new bearing/seal/right tools,use them and be done with it.

Got the clutch assy off, fristion material fairly worn but not drastic, i.e. rivets intact. It's about .125" thinner than the replacement. Flywheel looks fair, no gouges or anything that catches a fingernail, but plenty of striations and some "crackled" are that looks a little like a dried out lakebottom:
https://cimg3.ibsrv.net/gimg/www.rx7...812180afef.jpg


So here's the rear main seal just after removing the flywheel. Must be a small leak, the thing looks pretty good. Anyway I'll swap in the new one. This is so cool seeing the business end of the engine.

https://cimg3.ibsrv.net/gimg/www.rx7...5a0e887c55.jpg

Next up, find a guy to refinish the flywheel, get to cleaning everything.

This thread is awesome, very helpful, I appreciate all the time you're putting in to the pictures etc as you go through this adventure!

Clutch pretty worn for 35k. Look at discoloration in disc close to the hub,seen some heat,corresponds to heat check cracks in flywheel. Pressure plate likely has some heat stress on it to. Again thinking someone learning how to drive manual trans in this cars life-seen a lot of slippage/heat..Straightedge/feeler gauges on flywheel/pressure plate could show you how much warpage on each-not really necessary as you can see the results All adds up to give you that shudder on launch complaint you're chasing.
I have had to clean up/reuse flywheels like that and while serviceable they aren't as smooth as a resurfaced or new flywheel.

Rear main seal most always look good on disassembly,unless they are obviously leaking. It's after they're trifled with in R&R of flywheel they start leaking. What does front/seal side of flywheel look like? Sometimes damp from long term rear main seepage. Show a pic of flywheel where rear main seal lip rides,is there a mark or ridge you can feel with your finger. Take a pic further back that shows the whole of the back of engine to better pinpoint source of oil leak. Could be oilpan,could be longtime mess from oil filter changes.

You could use 1/4" 10 mm socket/ratchet and using two fingers go around oil pan bolts and lightly snug them,you're more looking for bolts whose tension has backed off over time from heating/cooling cycles.

Flywheel will look better than new when you get it back from machining. Personally feel properly ground flywheel is a work of art,shame it'll be hidden when all back together,lol. Clutch guaranteed to be butter smooth. So you know,it will engage closer to the floor than the worn original did. All new clutch discs do as result of thicker clutch lining than what was removed. After wearing in for a bit,not noticeable.

What condition is heater hose at back of engine under oil filter pedestal? Long term exposure to oil from filter when changing tends to weaken the rubber here. It will feel softer in that section than elsewhere in hose. I lost an engine in my GSL when this hose burst while at speed on highway. Engine empties of coolant pretty fast under pressure with the water pump helping to push it out-faster than the gauge will accurately register. In my case too late.

Hey thanks...I'm glad someone else is enjoying this too. I understand things so much better with photos...and the tech has gotten so good in smart phones that it's much easier to get a good shot.

I see what you mean, the distinct bands of black and brown of the friction disk, and it coincides with the most damaged area on the pressure plate. A shot of the old and new for comparison. I've got the new parts back in their packages to avoid any contamination.
https://cimg0.ibsrv.net/gimg/www.rx7...79c732315b.jpg



.

Ha! Maybe a bit of both. I'll go around the oil pan and check the 10mm bolts as you suggest. Here's the back of the engine prior to cleanup...it was filthy but dry toward the top and sludgy wet toward the bottom.

https://cimg6.ibsrv.net/gimg/www.rx7...c068fabaa6.jpg

Flywheel engine side looks pretty clean to me, in the detail picture there is some oil, but it's on the inside of the sealed area, where it ought to be. I'll take a closer look tomorrow at the side where it interfaces with the seal.

https://cimg7.ibsrv.net/gimg/www.rx7...0b7711d199.jpg https://cimg0.ibsrv.net/gimg/www.rx7...dbf49c4c34.jpg



.

This is exactly what I'm looking forward to.

I'll check it out, thank you!

Slight scoring on flywheel
 

Here's a shot of the flywheel "hub" on the engine side, that rides along the main seal. There's a slight score mark on the entire circumference, can just catch a fingernail but not deep. Still, it looks like it would slowly eat the new main seal.

In the RX7 Technical data ( link for manuals tech data: Foxed.ca - Mazda RX-7 Manuals) there's no spec for the flywheel hub size. Whatever the spec is, it looks like this one needs to be polished.

https://cimg0.ibsrv.net/gimg/www.rx7...d75b055086.jpg

That's a pretty good groove starting there. See that more on piston engines that had infrequent oil changes. That surface needs to have a very smooth finish so as not to wear seal lip prematurely. You could get the machinist to give you his opinion on polishing that while it's there for resurfacing. If it's bad enough,there are chrome repair sleeves that can be pressed on over that wear spot to give the seal a new surface to ride on. Again ask the machinist for his opinion. I've never done this on a rotary but have done several on domestic V8s and a Honda Accord V6 crankshaft with success. Machinist could measure od of eccentric seal surface on flywheel and cross match the dimension to another application.
Google 5.0 Ford crankshaft rear main seal repair sleeve to get a pic of what this sleeve looks like. Post back results from machine shop visit.

Got the flywheel back, looks sweet! The machinist wasn't worried at all about the scoring but he cleaned it up a bit. Didn't want to remove too much so he just polished the nose. It looks scored but doesn't feel scored.
https://cimg9.ibsrv.net/gimg/www.rx7...c39c8ca6ca.jpg https://cimg5.ibsrv.net/gimg/www.rx7...f24e32dcec.jpg

And cleaned up the bell housing. It actually went pretty well. Used penetrating oil as a solvent for all the grease/grime, sluiced the mess toward the bottom, sopped it all up, The brake clean to wash the remaining grime down. Impossible to take photos during, just too damn messy.
https://cimg1.ibsrv.net/gimg/www.rx7...c8d2880239.jpg

Pretty! Are you going to do the transmission seals as well?

Yes, front and back. I have the parts and no idea how to do it...yet. Tail shaft looks easy, it's right there on the back. The front seal must be buried behind that plate that the throwout bearing rides on?

Yep on the front plate. I use a big socket to tap the new one in. Be careful digging the old one out.

Wow! This is most informative and the pictures are VERY helpful. Thank you x 100000

Awesome, glad you're enjoying it. Half of the reason I take a s*&t-ton of photos is so I can put it back together the right way.

No progress lately, I only have time in fits and starts but I hope to get back on the creeper soon.

Do replace that pilot bearing. If you can get it and the seal out and the seal is ok, you can reuse the seal but its just not worth doing this over to deal with a pilot bearing failure.

I recommend the opposite. The bearing looks fine, just needs grease. The seal should be replaced as the rubber can got old and hard, and often damaged during R&R.

So Seattle to Huntsville is ~2200 miles, but I guess you guys are farther apart than that ;).

My reluctance to change it is due to not having the damn puller at $140 and I don't want to screw it up. I was relieved to see it looking pretty clean. There are no rotary shop tool rental places around here that I am aware of, Boston area.

There's this thread from 2011, using recommending at OEM Tools 27128 slide hammer puller rental from Autozone, but they don't seem to stock that anymore.

https://www.rx7club.com/3rd-generati...-works-957245/

My tool is the standard one from advancezone with the tongs on it slightly rounded to fit the meat of the metal against the inner rim of the pilot bearing better. Once you get it you will see what I mean. And they will just loan it for free, just don't let em know you modded it.

Is that a slide hammer type? I've got a 3 jaw puller that i was thinking I could mod like this, indicated by the red lines, final dims custom for our application.

https://cimg7.ibsrv.net/gimg/www.rx7...ab1ff3b963.jpg

I would use some aluminum stock and then wood to protect where the green arrows push against the back cover of the engine.

Yeah it fits on my slide hammer. That one you have might work but I would worry about it doing something to the rear iron. Sometimes those bearings are in there tight.

Looks like this and is only $15.00 if you already have a slide hammer.

https://www.autozone.com/loan-a-tool...hment/230517_0

https://contentinfo.autozonepro.com/...27059/image/3/

Already shared my opinion on how to proceed here...yes, the Mazda tool is expensive. Don't recommend using 3 jaw puller-modified or not. Pilot bearing needs the shock of slide hammer to move it. Even modifying puller to get behind bearing,it will likely deform it from steady pull,not what you want.

I have a blind bearing puller/slidehammer set that i use for this job. Essentially same tool as Mazda piece. Suggest looking on ebay,have several flavors,the ones there are reasonable, $25-$60. May not be best quality-but you only need it to work once and it will have paid for itself. The right tool gets bearing out in 5-6 taps of slidehammer-in one piece,best case scenario.

When I replaced my engine and did the Exedy Stage1 upgrade, light aluminum flywheel, et al - I tried all the tricks to remove the pilot bearing to replace it, because I didn't know how many miles were on the one in the replacement engine. Tried ALL the tricks, wet bread, wadded up paper, hammering in an undersized socket, grease - you name it, nothing worked. I gave up, ordered the Mazdatrix slide hammer with the right attachment, and in 15sec it was out, effortlessly. I've had to Dremel them out before, so I know what happens when you get pissed and just go at it.

This is one job where you want the right tool.

Awright awright! Jeez you guys are like the Greek chorus! </s>

OK, well, also you're all spot on correct and I can't thank you enough for your persistence and good counsel.

I ended up splitting the difference in a way, modifying a less expensive and readily available puller (HF) to fit a little bit more like the proper Mazda tool.

I'll post the details next. Did say thanks? THANKS!