Lateral-g Forums - Hydraulic Throwout Bearing Issues (maybe)

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- - Hydraulic Throwout Bearing Issues (maybe) - help! (https://www.lateral-g.net/forums/showthread.php?t=18646)

Quote:

Originally Posted by XcYZ (Post 193728)

Shafi, I don't see what pushing your kit has to do with the downshifting issue that James is seeing.

James, out of curiousity, did you check the bellhousing centerline alignment?

XcTZ,

The downshifting issue is very likely related to the clutch release issue. The clutch is not releasing cleanly. Once James get's the hydraulic bearing issue corrected, then he will next need to determine if the twin disk floater is moving cleanly and releasing the clutch.

Here's the "pushing sales" pitch, so brace yourself. Our hydraulic kits are a far more advanced and better design and we don't have these sorts of problems. Years ago before we discontinued the product in 2003, we sold many hundreds of the McLeod hydraulic product and the Street Twin clutch. We worked through these problems first hand, issued recall notices, issue repair/upgrade parts, issued replacement notices for the entire bearing.

In all fairness, my original post from yesterday fell short of conveying the proper level of information.

I guess my frustration with your post(s) is that appears, at least to me, that (as you mentioned on the PT reply) that you haven't read through the thread and are not addressing my issue. I appreciate your input and that you have a bunch of experience but your first reply here yesterday was a promotion for a product that you offer that does not fit my car - not a solution. Your post today, while informative, is also not applicable to my circumstance. I don't have a McLeod TOB...

I do agree that the clutch release and hydraulic 'system' is very probably the issue - especially given the appearance of the clutch (ie. not burnt up or abnormally worn) but again, your product does not appear to be applicable to my application (ie. Tilton 77 series MC with 900-series pedal assembly).

Quote:

Originally Posted by reboot04 (Post 193774)

James,
I read through ALL of this thread's post before replying today. The majority of what I posted regarding setup is relevant for the pancake style slip on CSC hydraulic bearings.

In fact, we do offer a solution for this unless I am missing something that you have declared in this thread.

Regarding your clutch, I am unsure how to read your comment about the pristine condition of the clutch. Indeed, the Street Twin clutch pictures presented are not of a pristine clutch, but one that is showing considerable signs of hotspotting and abnormal wear. I'll exit off this thread, and I wish you the best in getting it all worked out.

Checking the pictures of your flywheel and clutch components, there are a lot of heat spots for only 100 miles. That tends to lean towards your clutch not fully releasing or you ride the clutch a lot to get moving. I would doubt with a 6 speed you need to ride the clutch?!

I doubt this is in the transmission issue since up shifting is fine. Hopefully this will ease your mind a bit.

Downshifting a transmission is harder than upshifting one, as you downshift, each mainshaft gear is spinning faster than the higher selected gear you shifted down from. That is why you can easily shift 1-2-3-6 but you need to slow your vehicle speed down if you want to shift 6-3-2-1.

What ever you do, you need to resolve this before you ruin your expensive clutch and your Rockzilla. Maybe an engineered hydrauilic kit might save you some money.

Those heat spots may now cause clutch chatter once your other issues are resovled.

Thanks Jody, I appreciate you comments and agree. Those are the same conclusions that we've reached and we're addressing the hydraulic issues now. If need be we'll look at switching out the master cylinder to a 7/8" bore when we get the car to California.

I'll be watching this thread closely James. I did purchase an ATS modified TOB as well as the McLeod RST and am still quite a ways away from trying it out.

I do agree that those burn marks do appear to be a problem, especially with only a hundred or so "hard" miles on it.

Best of luck.

James , I hope things are getting resolved. I am yet to start my car & it has
the same or close setup from ATS. I'm not positive on which TOB I have, I think it's the McLeod bolt on. Very interested to see what your solution to problem is.

Peter

Quote:

Originally Posted by reboot04 (Post 190736)

I am going to be the first to admit that clutches (et al) are not my strong suit to begin with and the T56 and hydraulic TOB in the '67 is the first one that I have ever done (besides servicing in my old WS6).

That said, as a lot of you know I was having issues downshifting the car car at the Optima challenge - the car would upsift fine but when I tried to do higher speed/rpm downshifts the transmission wouldn't slip into gear. Heck, it wouldn't be forced into gear either... some times it would go with a little more aggressive blip but not always.

Opinions at the time ranged from transmission (doubtful - new by Rockland), to fluid (it was full), to clutch/TOB engaugement (possible), and hardware issues (but after inspection nothing is loose, backed out or missing).

So, out comes the transmission. At first look everything appears to be ok - nothing is loose or appears unusual. So, following some instructions I found on the RAM site I take some measurements to see if maybe the TOB needs a shim (which was one of the more common suggestions up front).

I measured the distance from the clutch fingers to the bellhousing mounting surface - 2.25".

I measured the distance from the compressed TOB bearing surface to the plane of the transmission mounting surface - 2.4"

It would seem to be (and as admitted, I am a far cry from an expert here) that the TOB isn't compressing enough and that based on these measurements there is pressure on the clutch fingers all the time.

so...

Does anyone have any suggestions, ideas, or recommendations on what these measurement mean and what remedy there may be?

My first thought was maybe bad TOB?

Any help would be appreciated.

Thanks,
James

I had the same problems like you James. I´ve tko 600 and pretty much the same combo on my vette. I had difficulties tu shift up and down on high rev (above 2500). The problem was that I had a slight pre-compression on the clutch assembly and for that reason it didn´t reliese the clutch fully when driving hard. -> That way the sncrons won´t work the way they should and it is hard to do shifting. Let me know I´m just speeking BS, because I have learned thise things by doing something wrong in the first place.

That is my best quess right now.