964 clutch options and "while in there" items

[perelet]

Originally Posted by iamtheari

Oleg.....

It appears that you're just doing a top-end rebuild. How did you decide to do that? .....

Oh, I had no plans to take it apart at all! Millage vise my engine is "just broken in". It was bloody dilavar stud.

That said once I took it apart - cylinders still have honing marks, valve play is well within spec. Clutch thickness is also within spec.

Based on what I see . If you have well documented car, had it for several years, your engine has less tan 200k miles and has no visible signs - do not take engine apart.

Oleg.

[wesleyc]

Not trying to hijack a thread. But I hope your right Oleg? I just dropped my 95 993 for clutch/flywheel. At 126k choosing not to do top end. I've not done a leak down and it's leaking oil so bad now that consumption is questionable. It didn't us oil before so no top end.

[iamtheari]

No worries about thread jacking. Adds to my knowledge too.

I am progressing on the engine drop. The manual says to disconnect cable terminal 30 from starter (in addition to the ground strap to the body). Does anyone know where this terminal 30 can be found?

Also, what size socket do I need to use on the clutch slave cylinder? It's a tight space and I would rather get a hint than bust my knuckles trying to reach in repeatedly with different sockets.

Next up, some have said that you can disconnect the throttle cable at the throttle body. I did that, but it appears to be fixed through a bracket that is attached to the engine. Is this going to work or should I just go back to the workshop manual method of pulling the cable out to the rear and leaving it attached to the engine?

Pro tip: People say to use a 19mm ratcheting wrench to remove the top bolts connecting the central tube to the transmission. This is correct advice. What they forget to mention is that the complete set of GearWrenches you just bought only goes up to 18mm.

[wesleyc]

I disconnected wires going to the battery /ground strap to body. Slave cylinder is a 13mm. ( I had to use regular box end. Gear wrench was too fat ). I tried pulling throttle cable from peddle but it got hung up @ about 2ft. So I dropped the engine a bit and disconnected at engine and fed cable back through after pulling grommets.

[iamtheari]

Thanks... It's hard to see all the wires on the starter, unfortunately, and I've never held one in my hands so I don't know which wire is which. Does anyone have an idiotproof diagram handy?

[iamtheari]

Another question: Does the pressure plate / flywheel assembly have to be balanced as a unit or is it safe to piece them together? If balancing is necessary then it changes my vendor options quite a bit, unless the local tire shop can balance the assembly for me which I haven't called to ask yet.

[johnsjmc]

Originally Posted by iamtheari

Thanks - I thought I was losing my mind for a moment there.

Any experience with those parts? I don't think my little 964 will ever put out such torque as to benefit from greater clamping force than it already has. Or, at least, the cost of modifying the engine to reach that level of torque would make a GT3RS pressure plate a drop in the bucket. But the GT3RS part seems to cost the same or even a few dollars less than the 964 Cup part, so unless we're talking about the pedal effort difference being enough to make my left leg disproportionately hefty, I could just as well go with the upgraded one.

That's the problem with these cars. There are too many possibilities for anyone to have tried them all. Except maybe Bill Verburg. Thanks again for weighing in on this one, Bill.

I,ve used the gt3 pressure plate in a 993 and then removed it and reinstalled a stock 993 pressure plate instead. The stock 993 plate is about 10% stiffer than a 964 PP but still about 20-30% lighter than a GT3 or turbo PP.
My stock setup lasted 110,000 mi so unless you need the extra clamping because you are turbo or supercharging it I wouldn,t bother.
Your left leg will never forgive you if you do.

[johnsjmc]

Originally Posted by iamtheari

Another question: Does the pressure plate / flywheel assembly have to be balanced as a unit or is it safe to piece them together? If balancing is necessary then it changes my vendor options quite a bit, unless the local tire shop can balance the assembly for me which I haven't called to ask yet.

The replacement part should be balanced from Sachs to begin with. The mfg tolerances should be good enough for most applications
If you do decide to rebalance it a tire shop can,t help you .Engine rebuilders will either have the equipment or will send out the components for you to someone.

[iamtheari]

Just so I understand clearly: A fresh pressure plate should be balanced from the factory, and a fresh flywheel should also be balanced from the factory, so they do not need to be balanced together unless I have some special needs?

In other news, a couple of items have come up while working on dropping the engine. The starter is still completely foreign to me. It seems like it was deliberately designed to be impossible to disconnect while it's in the car. Does it become easier after the engine is lowered a couple of inches or should I keep hacking away at it now while the engine and transmission are safely secured to the car? Does anyone have a good picture showing precisely which fasteners need to be undone?

The other one is the longitudinal slave cylinder. The small allen-head bolt rounded out for me so I had to use an Irwin Bolt-Grip stuck bolt extractor. Fortunately I had one the right side. But the "lock" that supposedly slides right out seems to be firmly planted and there isn't any obvious way to grab it and pull. Are there any tricks here?

The clutch slave cylinder is also deliberately designed to be impossible to work on, as I already knew from experience bleeding it. But removing it is even harder. I got the lower nut loose but the upper one is just impossible to reach with a wrench unless you have longer arms even than I do (mine are not exactly short). I decided that I can probably get a better angle on it once the engine is lowered a couple of inches. If anyone knows of why this is a bad plan, please speak now or forever hold your peace. (Or at least don't laugh at me when I come back later and say how I learned it is a bad idea.)

Okay, that's it for today. If I can get the longitudinal lock's "lock" out and the starter properly disconnected, I can start to lower the darn thing at long last. Thanks again!

[iamtheari]

Update: The yellow wire on the starter solenoid was being stubborn because the whole bolt was turning. Once I held the lower nut still and got the upper nut loose, it came right off. The starter now appears to be free. I was able to torch and then cold-chisel the PDAS longitudinal lock's locking key out to an angle I could pull it free with a vice grip. And I got the clutch slave cylinder out with all my knuckles intact.

The remaining complication is the longitudinal slave cylinder fluid line. The instructions both in the workshop manual and in every other source say to lay it to the side to the line clears the transmission. However, the route of the hard line makes this seem impossible. The slave is forward of the transmission mount cross-member. The hard fluid line runs above the cross-member / below the transmission and then to the bracket where it attaches to a flexible line (as does the transverse lock's fluid line). What "route" do people take to get the lock clear of the transmission so you can lower it?

[iamtheari]

Success! Obligatory photo in engine bay. I'm not necessarily proud of how I came out of the process, but this photo does two things: (a) induct me into an elite group of Porsche owners and, more importantly, (b) remind me to wash my face before I go to bed so my wife doesn't kill me in the morning.



If it helps anyone in the future, the PDAS longitudinal slave cylinder solution (regarding my previous post in this thread) was this: Disconnect transmission cross member and lower it 1 inch, then pull the hard line out toward the driver/left side of the car until it clears the cross member and can be moved freely beneath it, and then it was possible to tie it out of the way.

Tips on the final step of lowering the engine:

Watch the axles very carefully as you lower the engine. I went slowly, an inch at a time, but somehow didn't see them catch (especially on the passenger/right side of the car where the starter interferes with it). The steel wire I had used to hold them in place broke and I had to wiggle the engine/transmission assembly side-to-side a few inches in order to get the axles to clear it again.

Lightweight steel wire is probably insufficient to hold the central tube. I used two strands, tied off and bolted down to the central tube cover studs (just like you would with the self-made tool that the workshop manual calls for). One broke, quite likely due to the weight of the transmission bearing down on it in addition to the central tube. The other remained intact the brief moment it was stressed later in the process but mostly I ended up bracing the central tube with a jack stand and a big chunk of wood to make up the difference.

Be careful that the wiring harness on the top center of the engine is pulling cleanly through and not pulling against the little plastic bracket that holds it against the front of the engine bay.

Be very careful if you have to jack up the car while the engine is not mated to it. It does not behave the same as it does when the engine is part of its mass, which may result in it handling differently than you are used to. Even with the rear bumper off, I had to get about 3 more inches of clearance to get the engine out of the car. The problem was that the ATV jack I used could not go high enough to reach the engine when the car was sitting on my jack stands (the flat top kind that Pelican sells, set to the tallest position), so I used a couple of layers of dimensional lumber between the jack and the engine. Thus, it did not get all the way down to the lowest point on the jack. I used a normal jack on a rear suspension member to lift the car up, but it twisted slightly on the front jack stands as the jack lifted and pulled it toward me slightly. This made me extremely nervous. I could have alleviated this effect by sweeping the garage floor perfectly clean around the jack before lifting the car, as the jack then would likely have rolled more freely on the floor and put less rearward force on the car (rearward on the jack = sideways on the car).

I got ambitious and tried to split the engine and transmission. I got the starter off, but need to get ahold of a long M6 bolt in order to remove the release fork shaft. This step in the manual is not explained very clearly and I briefly sang the Previous Owner Blues because I thought there was a bolt missing from the car.

Now, for a weird one. There was a whole mess of zip-ties holding some wires to various parts of the car, which I had to clip as I lowered the engine/transmission assembly. There are two rectangular blocks that appear not to have any labels, which were bolted (by a little angle bracket on each of them) to the mounting bracket that holds the fluid lines for the PDAS locks to the transmission. They each have two wires coming from them, and the wires then seem to be joined together (I don't remember sitting here in the warm house if they were in parallel or series) and go to a cylinder.

The cylinder appears to be a capacitor of some sort, labeled COMPUTAMER with some handwritten numbers and preprinted MFD and VDC. If the numbers written on it are to be trusted, it's a 25VDC / 42,000 MFD capacitor. This is then wired in with the starter from the appearance of it. It is permanently connected to the wiring harness on the engine side of things. I don't know what kind of connection was made as I did not yet remove the mass of black electrical tape that is protecting it.

By all appearances, this entire clump of wires and parts is aftermarket. Does anyone know what its purpose might be and whether it is a useful modification? Or should I just hack it off and return my wiring to stock?

[iamtheari]

Scraping off dust and grime, I found that the label on the capacitor is COMPUTAMITE and that the two bricks are Alternator Noise Suppressor, Model No. ANS-80 from Pacific Accessory Corporation in Santa Ana, California. They are wired in parallel with each other, and in series between the capacitor and the alternator. The other end of the capacitor was wired to the starter.

Here is a diagram I found online for the ANS-80: http://pix.crutchfield.com/manuals/127/127ans80.pdf

Note that it's hosted by Crutchfield, which implies that this whole setup is audio-related. The car had an aftermarket stereo head unit when I bought it. There are a few stray speaker wires that make me suspect that a subwoofer had been mounted in the car and removed before I bought it, in all likelihood before the previous owner bought it.

I have since put in a nicer head unit but I don't bother with subwoofers and all that jazz. This car is made for driving and, when you're driving it properly, the stereo is kind of overwhelmed by the engine noise. Doubly so if I bypass what's left of the exhaust.

So I am tempted to ditch this contraption, but don't want to screw up the big red wire from the alternator. I'll have to take a look at the factory wiring diagram and the usable length of wire from where this mess was spliced in to see if I will have to do a new splice or just solder a new ring connector on the end.

[iamtheari]

Ran into one more pair of stubborn fasteners: the TOB guide tube screws attaching it to the transmission. I've applied an impact screwdriver, a night of PB blaster, and some time with a torch to no avail. I don't suppose anyone has a trick other than drilling them out that I can try.

[johnsjmc]

If you haven,t peeled out the center of the screws with your impact screwdriver yet, you need to hit it a bit harder. The screws should come out BUT be prepared to ruin them in the process.
(also make double sure the impact driver is set on counter clockwise)

[iamtheari]

I got them out. I need up drilling and using the spiral screw extractor on them. Someday, I will buy a better impact screwdriver. Mine is a Harbor Freight tool and the rubber handle is a little sloppy to get anything done. That said, it was handy for the pressure plate bolts. Two of those got a little rounded out because I didn't clean them out enough before trying to remove them. The tool has a 1/2" drive head so I was able to out the triple square socket on it and hammer enough to break the bolt loose.

Today's challenge: I am going to replace the flywheel seal. This was a good idea before, but now that I have begun to try to get the old one out, it's an even better idea. Any secrets to success here?

[nickd]

Wow, just read through the last few entries. I think that everyone goes through all of these exact issues.

Flywheel / rear main seal is easy. Just insert the new one so that it's flush. I dunk these kinds of oil seals in fresh oil so that they go in easier, and without tearing.

Impact screwdriver is exactly the right tool for the guide tube screws. And the correct size phillips bit. Pulling the old guide tube seal out is a pain too. I poked a couple small holes around the circumference, then used two L-shaped dental picks into the holes to tug it out. New one presses in easily.

Pressure plate bolts have a pretty shallow head. Easy to strip them out. Definitely want to replace all of them with new.

Have fun

[iamtheari]

Getting the seal in sounds easy. Getting the old one out has been my trouble. I put a screw into it and pried out--just to pull the screw through the seal. I am tempted to start a total overhaul just to get to the darn thing. I did get replacement pressure plate and flywheel bolts, not to mention axle-to-transmission bolts and a few other replacement fasteners for those stubborn ones that suffered any damage or required any heat to come out. Glad to know I'm not the first to sail these rough waters. It's definitely fun overall, but driving the car more is the real fun part I'm working toward!

[nickd]

Try something like this to pull the seal-

Sears.com

Two of the right-angle hooks in a hole punched into the seal, should be enough to wiggle it. Anything similar should work.

The clutch fork rod was my personal favorite. Took me hours to pull that $%^ out!

[johnsjmc]

Originally Posted by iamtheari

Getting the seal in sounds easy. Getting the old one out has been my trouble. I put a screw into it and pried out--just to pull the screw through the seal. I am tempted to start a total overhaul just to get to the darn thing. I did get replacement pressure plate and flywheel bolts, not to mention axle-to-transmission bolts and a few other replacement fasteners for those stubborn ones that suffered any damage or required any heat to come out. Glad to know I'm not the first to sail these rough waters. It's definitely fun overall, but driving the car more is the real fun part I'm working toward!

I think you are referring to the large rear main seal behind the flywheel. Push a screwdriver thru it at the crank edge and pry it out. Installation is simple use a piece of 3 inch plastic drain pipe cut square about a foot long and drive the new one in. Light smear of oil on the inner diameter so it doesn,t start up dry. Some will use a non hardening sealer on the outer diameter others won,t bother and will smear oil on the outer surface too ,to ease install.

[iamtheari]

I actually bought the same set of picks from a different brand at a tool store this weekend. I will try to get two at 180-degree angles to each other and wiggle the seal. Just one of them didn't do the job. Thanks for the tip.

The clutch fork shaft wasn't so bad for me, once I figured out that the proper tool is a bolt. Porsche is so unpredictable in the workshop manual. A 10mm allen socket is a "special tool" but an M6 bolt is normally in your toolbox?

It's turned out to be harder than anticipated to find a ring terminal that fits on the alternator wire. The O'Reillys, Sears, and hardware stores I've looked in have all come up short with the largest-gauge ring terminals in stock being 10-12awg. I estimate that the alternator wire is a 2awg. I don't want to put all that 1990-era aftermarket stereo junk back in the car with the engine.