charlieaf92

Thanks Joe! I actually just found that as well. It looks like the lower bolt hole is easier to align and then you can lever against it to get the top one lined up. I just went out and checked and that does seem to be the case - I just need to find a punch or similar sized tool to use. Its quite difficult to get the lower bolt started first.

Cheers
Charlie

charlieaf92

Well today was a failure all around. After struggling for hours using a punch the slave cylinder finally just went right into place with almost no resistance. I couldn't believe it. Well, the success was short lived. After getting things tightened in place I tried the clutch pedal - first with my hand after reading of problems others have had. It was stiff - too stiff to push with my hand. So, I got in the car and pressed with my foot - initially lots of resistance and then, boom, all the way to the floor. My suspicions were confirmed when brake/clutch fluid began leaking out between the transmission bell housing and the engine. I can now 100% relate to the expression others have used of 'inventing new swear words'.

So, the slave cylinder is blown apart. I removed the transmission and collected the pieces and have reached out to the Porsche dealer to find out how quickly I can get a replacement. So - that being said, I am wondering if its possible to reassemble the slave cylinder or if it is just best to replace it?

I've also completely removed it from the line and plan on installing it with the transmission dropped. Perhaps I was just mis-aligned when trying to put it in, but I honestly it seems just about impossible while the transmission is in the car. There also does not appear to be any way to verify the alignment with the fork while in the car.

Cheers
Charlie

Flat6 Innovations

This is the most common issue related to installation of a used slave. Often the rod that actuates the slave loses its center with the internal piston during installation, due to side loading. When this happens the exact situation that you mention will occur, an extremely hard pedal, then immediate failure of the slave. I have only been able to save a couple of these when this occurs, and that's if I had a parts slave to rob some pieces from.

Copilot

Jake, I'm going to be doing the same thing when I put my engine/transmission back in next week. Would the best way to do it be to remove the slave from the line, bleed out some pressure, install the slave, reconnect the line, and then bleed the system? Definitely want to avoid any issues.

Thanks to the OP for sharing - as I'm following you in my project it's helpful to have some of the points you've mentioned.

Flat6 Innovations

I pop the bleeder and remove some fluid before removing the slave, then remove the slave and use a mityvac to pull a little vacuum and retract the piston and rod.

Copilot

Thanks Jake!!

AWDGuy

ugh, that sucks. I remember trying to get it back on. I was so set to not loose any fluid and tried and tried to get it back on. finally I popped it open, left it open while I installed it and had fluid all over me.....but it worked. had to re bleed the entire system but it was probably due anyways.

Slakker

How high do you need to lift the car to be able to get a transmission jack in and roll the transmission out/in?

charlieaf92

I just measured and mine is 15" from floor to the top of the jack stand holding the car. That is pretty close to the minimum - any higher and the job is easier. I was reluctant to go higher due to fear of losing stability.

Slakker

I think with a set of liftbars I could safely lift it up to about 19". Do you think that would work? What transmission jack are you using (sorry if it was mentioned earlier in the thread.)

charlieaf92

I'm not qualified to answer that question. All I can say is use common sense and be careful. I put the rear wheels under each edge of the car as an added safety measure and always have someone home (and most of the time in the garage with me) while I'm working underneath the car.

I've seen some members have their cars high enough to roll the entire jack out with the transmission on it. That would be ideal as long as you're able to safely get and keep the car in that position.

I'm using the red transmission jack that harbor freight sells. It's ok and pretty inexpensive. I found raising it with the tranny on it takes some effort, especially from the lowest position. It gets easier as it goes up. I've been using an air impact gun to raise it.

Im happy to answer any other questions - good luck!

Schnell Gelb

Go easy with the impact - you talking about a Harbor Freight lift not an OTC or Gray! I have the HF .I have an M96 on it now.
Suggest you carefully lubricate all the pivots ,pins and moving parts with engine oil until it drips off.With no load on it , raise and lower it -I use a speed handle.Then lubricate it again and repeat.Now it is ready.No need to force it.I just use a ratchet when it is under load .
Have a plan in case something breaks ! Safety straps /lift straps nylon webbing even rope?
The HF lift is great because it is mechanical ,not hydraulic so it seems less prone to failure?

charlieaf92

I think we're close, really close!

So I'm waiting on a Motive bleeder that I ordered (should arrive tomorrow). The new clutch slave cylinder arrived today so I installed that.

The transmission was out (underneath the car) and I installed the slave cylinder there. It was MUCH MUCH MUCH easier (obviously) because I could see what I was doing + the new cylinder had no fluid in it. Once it was installed I put the release fork on with the throw out bearing and it all fit tighter nicely. I was able to 100% visually confirm that the slave cylinder was properly aligned. That being said, the cylinder does hold the release fork forward - it is still able to sit on the guide tube, but if you aren't careful it could fall forward and come off the tube. If this happens, you won't be able to install the transmission because the bearing will get pinched between the pressure plate and the guide tube.

I didn't see any reason why the transmission couldn't be installed with the slave cylinder attached so I decided to give it a shot. And... it worked. Perfectly. There was no noticeable resistance holding the transmission off the engine and things went together smoothly. Honestly, if I were to do this project over I would just unhook the line and pull the transmission with the slave cylinder attached. The risk of mis-aligning the piston and blowing it to pieces - then having to take everything back out to fix it - just seems too high and from what I can see there is no way to visually (or by feel) confirm its aligned properly while the transmission is attached to the engine. The downside to this approach is that you have to bleed the system and you'll get brake fluid on yourself and the garage floor - but the upside is you won't do what I did and destroy your slave cylinder and have to pull the transmission out again (I am getting quite good at it though!)

Now that I've removed and reinstalled the transmission several times, here are some tips.

1. Get the clutch aligned, perfectly. With it aligned, it is not a terribly awful job. With it mis-aligned it is a nightmare and impossible. I used an alignment tool and it didn't work - what ended up working was eye-balling it and using the alignment tool to help nudge it as needed.

2. Go slowly! It is a tight fit so you must raise the transmission with it more towards the front of the car until the bell housing can clear the rear cross-member. Once it can clear it, you can slide it back towards the engine to give yourself room up front. Keep in mind, as this is a C4S I think the transmission is a bit longer and required me to raise the transmission with the upper bracket already on top of it. This added to the complexity because there are some delicate hoses that the bracket can crush if you don't take your time and check regularly.

3. Raise the transmission to the appropriate height by referencing the block and the bolt holes and then push them together. As the transmission input shaft comes in contact with the clutch splines - rotate the output shaft (you'll need it in gear) to help things mate up properly. Once they do, it will slide together a little further and probably stop with about a 1/2" gap between the bell housing and the engine.

4. At this point, alignment is crucial. I found that using a light you can peer through the side of the rear passenger wheel well and see the two surfaces (bell housing on transmission and crank case). Eyeball them to see that they're parallel and spacing is even from top to bottom. Adjust your engine height using a jack as necessary to get them parallel while keeping the transmission at the correct height using your transmission jack.

Once they look good, try wiggling the transmission and pushing - they should slide together without too much effort.

Onto the front transmission mounts...

So, on the C4S there are two sets of bolt holes in the underbody where the upper transmission bracket goes. I looked online and it appears that in the tutorial pictures there is only 1 set. I chalk this up to a slightly different transmission? Either way, the set of holes toward the REAR of the car are the correct ones. The holes towards the front are too close together and from what I can tell serve no purpose.

There are two leather-ish guards that go on either side of the transmission, between the transmission and the bracket. Look at the discoloration and shape of them and you should be able to determine their orientation and what side is which.

The shifter cables are quite a pain in the butt. The top one (white) wasn't too bad, but I am having a really hard time removing the old retaining clip for the lower (green) one. Going to tackle that tomorrow.

One other thing, and I almost made a foolish mistake here. I decided to install the oil filter and go ahead and fill the engine with oil. Right before I poured the first quart in, I realized I hadn't replaced the drain plug o-ring and torqued it yet. Whew! With a project like this, start a checklist of important steps and their sequence so you don't end up forgetting something.

That's it for now, tomorrow I need to finish the shifter linkage, reverse light plug, bleed the clutch, CV bolts, re-install lower plastic covers, check the oil one more time, reconnect battery, lower it down, and hopefully go for a drive! In this case, to the DMV so I can get plates as my temp tags expired a few weeks ago.

Cheers
Charlie

meirschwartz

Great job Charlie, and excellent write up.
Glad to see things worked out for you, and also good to know that the slave cylinder can be installed on the trans, off the car.
Bleeding the clutch line should be a breeze with he motive, just make sure you keep high level of fluid in the reservoir.

Schnell Gelb

Charlie,
Thank you for including all the problems and mistakes. So often these jobs are given cursory and dismissively 'easy job' description. That is not helpful.Your saga is truely helpful.Specifically ,saying 1/2 clearance and then snug it up easily is so useful because there is a great temptation to force it in....not good !
Has anyone got a better alignment tool ? Jake mentioned making a hardwood piece but he did not say if he carved splines into it or just used a plain dowel. A carefully sized aluminum or copper rod or tube might work. A modified brass drift ?
I got (dumb) lucky when I used a cheap plastic Clutch pilot tool that was intended for a Ford Explorer for the M96(Bxstr S) on my bench now. The major o.d. is 1" x 23 splines .The pilot is 19/32"
https://www.summitracing.com/parts/ram-5311/overview/
A piece of domestic 3/4" copper tube may be useful for this size because the o.d. is 0.875" and the root of the splines on my cheap plastic tool is around 0.9".