G50 Clutch + While You're in There...

[mziggy16]

At 151k miles and with a stiff clutch pedal I knew it was a matter of time, and that time was this past Saturday. I was close to home and the clutch started to slip as it struggled to engage in gear. I have a list below and would like any quick feedback and some thoughts on specific questions below. Thanks to the forum archives for helping me get this list together so far.

Clutch Questions:
Thoughts on replacing both the master and slave cylinders?

While You're In There (WYIT):
Fuel Lines: I have factory lines. Is the guidance to replace only the lines in the engine compartment?
Starter: No current issues with the unit, but at 151k miles and the engine dropped, is this worth knocking out?

Thanks,

-Mike

[almostordinary]

Following.

Thanks

[Cory M]

Personally I wouldn't replace the master/slave cylinders or fuel lines unless there is a problem.

The mounts for the clutch fork pivot shaft are a known weak point. The bearings in the pivot can seize up and the bosses break. I recommend doing a very thorough inspection. Worth doing a dye penetrant inspection if you can to identify cracks. I would replace the pivot shaft and bearings with new parts. I believe this part (bushings/bearings) was redesigned by Porsche at some point, so there should be documentation out there. I had them fail on my transmission and I sent it to California Motorsports.

https://californiamotorsports.net/collections/porsche-g50-transmission/products/cms-g50-993-gt3-clutch-fork-pivot-shaft-boss-repair

Inspect your guide tube as well. If it's worn out replace it. I've had them hang up on the new throwout bearing because of wear causing friction and binding(this was on 915 but same principle).

The rubber transmission mount bushings could be replaced while you have it apart.

Edit- I see now that you have the guide tube and pivot shaft on the list already.

[2.7RS]

Grease CV joints and new boots

[cmcfaul]

I changed my G50 clutch about a year ago. Did the fork upgrade and the non rubber disk clutch. I also ended up replacing both the master and slave. The gunk that was in the lines at the slave was nasty. Glad I did both while in there. Getting the lines back on the slave is a bit of a pain so I would not want to have to do it twice. With that many miles, I would replace.

Stock clutch works perfectly and will do a minor burnout without having to dump the clutch too aggressively.

Chris

89 Carrera

[Marc Bixen]

You may want to look into this also, updated thicker ring gear, if yours shows wear or if it ever grinds: 950 116 143 05. Most times you will need a slave because the plastic tip wears out! And I STRONGLY recommend using the factory roller bearing cross shaft, NOT the bronze bushing style! Poor or old lubrication of the bronze bushings can lead to premature failure of the case ears as Cory M speaks of. High clamping force pressure plates also cause these failures. CMS's repair is very well executed if necessary. ,Also, if you do the valves, get a complete VC gasket set . Wrightwood Racing is the best. Some others use very soft alu washers, that can be a problem next time.

[mziggy16]

Good info and helpful.

I did the valves ~1000 miles ago. It was my first time, so I want to do them again since I have easy access. Can/should I re-use the hardware or just spend the $40 and start fresh?

[dtxscott]

Both speed and reference sensors and the CHT.

[mziggy16]

Got the big lump dropped this week and will start tackling things as parts roll in.

Couple of questions:

What are opinions on replacing things that are original but not broken? For example:
Starter
Speed/Reference sensors (CHT was done about 10k miles ago)
Master and/or Slave
Fuel Lines

Also, the hose below with the frayed end was not connected to anything and I haven’t been able to figure out its purpose. What is this?

[almostordinary]

Mike, you would be a life saver if you documented this in pictures. I am currently putting my puzzle together. Got an 87 Roller with everything stripped. The line you're asking about is the same in mine, but was one of the few things left in the engine bay.

I rebuilt my pedal cluster, so new master in there. And my G50.01 that I purchased was missing the speed ref sensor, slave was toast and a myriad of other parts (bought new slave, speed ref sensor, a few rubber seals, but lots to go.) ... so your post will be a needed guiding light for me and I'm sure others on here.

Luckily I have the release fork and clutch control shaft... everything else is coming out of my bank acct.

Also, what is CHT?

Thank you,
Ian

[mziggy16]

Originally Posted by almostordinary

Mike, you would be a life saver if you documented this in pictures. I am currently putting my puzzle together. Got an 87 Roller with everything stripped. The line you're asking about is the same in mine, but was one of the few things left in the engine bay.

I rebuilt my pedal cluster, so new master in there. And my G50.01 that I purchased was missing the speed ref sensor, slave was toast and a myriad of other parts (bought new slave, speed ref sensor, a few rubber seals, but lots to go.) ... so your post will be a needed guiding light for me and I'm sure others on here.

Luckily I have the release fork and clutch control shaft... everything else is coming out of my bank acct.

Also, what is CHT?

Thank you,
Ian

Ian-

CHT = Cylinder Head Temp Sensor
https://www.pelicanparts.com/techarticles/911_cyl_head_temp_sensor/911_cyl_head_temp_sensor.htm

The Bentley, the 101 Projects book and a verrrrrry helpful friend/neighbor/forum member were key to the current and future state for me.

Right now everything is fully assembled but removed from the car so happy to snap pics along the way of anything specific to your project. Shoot me a PM with what is most helpful.

[almostordinary]

Amazing. Thank you.

[wazzz]

Small hose connects to a nipple on the airbox.

[mziggy16]

Any concern with the wear shown on the ring gear? It shows this consistent wear pattern in the same three spots around the gear.

[cmcfaul]

All the fuel lines in the engine compartment for sure.

Chris

[mziggy16]

Couple of quick follow up questions that got lost in the shuffle:

1. Ring gear above. Is this wear okay?
2. Starter, now with the image below. Thoughts on this wear and replacing?
3. Speed/Reference sensors: No current issues. Replace or leave?

151k miles.

Thanks for everyone's help/input.

[PeteKz]

Run the ring gear, replace the starter gear. Or replace the whole starter proactively if it's old. If you go that route, consider the new lightweight starters too.

[mziggy16]

Originally Posted by PeteKz

Run the ring gear, replace the starter gear. Or replace the whole starter proactively if it's old. If you go that route, consider the new lightweight starters too.

Helpful; thank you.

Just to be sure, is the lightweight starter you're referring to the WOSPerformance version:
https://www.pelicanparts.com/More_Info/WSPLMS1102.htm?pn=WSP-LMS1102&fc=Y

[PeteKz]

Yes, that's it. And for that price, I would just replace the whole starter.