Rettax3 wrote:I'm having some issues with the concentric slave/TOB on the GTU's six-speed F40, the factory crap is all plastic junk
Dropped the F40 today. I think it might have actually been easier to pull than the 282 was. It is hard to say for sure though, since I took the time to pull the rear left engine mount off of the 3800, something I didn't ever do when dropping the old 5-speed. Even still, the engine didn't want to move much inside the bay -it is just really secure in there, I don't want to know what it would take to make it come out of there any way other than deliberately.
So, sure enough, the chintzy retaining-ring on the concentric slave/throw-out bearing popped loose -probably my fault really, I knew that these conversions typically require a spacer between the TOB and the clutch fingers, that is well documented on the Fiero sites, and V-8 Archie
even produces a part for this- but I thought the modifications I've made to the transmission and the thicker 3800 flywheel brought it all in together close enough -I was wrong apparently. I need to go over my notes and see if I mis-calculated or if the clutch diaphragm just has more travel than anticipated. So, it is time to make some spacers for this.
I also need to research the '01 GA master cylinder I have in the car now to make sure the piston isn't so big that it will cause the TOB to over-extend anyway, like the Fiero ones do, or I may have to shim-out the master away from the firewall to keep it from doing that, which will put the pedal closer to the floor and shorten my pedal-throw.
Yuck. I don't think the piston is too large though, the pedal feels too soft to be loosing that much hydro-mechanical advantage over the slave cylinder... Luckily, it doesn't look like my TOB was damaged, just popped apart -I still say it is cheap junk. Since it all worked for a while, I may not actually have any design-flaws here, especially considering the under-sprung feel of the clutch-pedal and the clutch engagement point I was feeling low towards the end of the pedal travel -the TOB may have just failed because the retaining ring is a serious weak-point (probably on purpose to provide a non-catastrophic failure-point) on a generally cheaply-built POS. I 'love' the newer GM stuff so much I want to sing, "Have you driven a GM.. Lately?"
While it was out, I also took the time to wire-wheel the left sub-frame clean, removing all grime and rust. I started on the lower A-arm too, but it wasn't very dirty and the original paint was mostly intact with virtually no rust, so I just cleaned it chemically. I coated it all with an industrial gloss black paint -pretty strong stuff, I've used it on a couple of engine mounts, and it stands up to abuse pretty well. I'll snap a pic or two before I put it all together... I won't be doing the right sub-frame any time soon though, it doesn't need to come out of the car right now, and it is covered in grease (a good rust-proofing all its' own) from the power steering line that went bad last year, a seeping CV joint boot that came with the old five-speed I had first put in the car, and a leaky oil-pressure sender, plus all the 20-year-old grime that was on the thing when I bought the car and first swapped-in the 3800 in the dead of winter a few years ago. My wire-wheel (actually a wire cup, for my angle-grinder) is now mostly gone, shedding the remaining bristles like a cat in summer, so I would need a new one first anyway. Or a chisel.