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BillyTheKid

5-speed installed today and...

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well, I think I might have a slight problem that maybe you can help me out with. There are three things that have me losing sleep tonight...

1) the clutch feels very weak...almost non-existant. Unbeknownst to us as we attempted several times to stick the transmission in and couldn't get it past the last 1/2" or so, through a little detective work (pulled out the transmission, took out the arm and t/o bearing and it went right in...come to find out the slave was seized). I eventually got it to break free through a little pursuasion, and rolled the dice by going ahead and intsalling it anyway...bled it and...it works, doesn't ride the clutch any but just feels like there is nothing there (I did see if the clutch was engaged fully by stopping the car while in gear, there was no slippage). It allows me full access to all the gears and doesn't creep while the clutch is in...but there is hardly any resistance...could it be a bad slave? After my test drive I put the car back on the lift and bled it again (this time the old-fashioned way)...same result.

2) when I installed the drive shaft I loosened up the diff and had to pull it forward a bit (all the way to the stops) to allow it all to be bolted up...however it looks as if the guibo is being pulled toward the rear of the car (i.e. the guibo is a tad deformed...about 1/8 - 3/16" from stock/vertical). Is this okay, or will this lead to premature guibo failure? Do I need to loosen the motor mounts and try to get the engine to come back?

3) I installed an aluminum flywheel with a stock (new) clutch...unfortunately the local machine shops are about worthless so i took the chance of not having it balanced beforehand (having replaced flywheels and clutches on VW's before without any work done prior...didn't have any problems...ever). Anyway, I noticed a very, very slight (new) vibration in about the 2500 rpm range...is this going to be something catastrophic or am I being hyper-sensitive since the clutch thing has me worried?

Again, I'd like to hear any of your inputs...especially regarding the slave!

Cheers,

Bill

edit: I didn't want it all to be 'worry' or bad stuff...I did get the engine tuned 'just right' and with the new header wrap and new exhaust gaskets...she's nice and quiet in the engine compartment (all that is heard now is the low IE stainless exhaust). During the brief test drive, I didn't notice any driveshaft-induced vibrations (though i was only able to get it up to 50-55...and on base that is a big no-no). She did go through all the gears and felt great...compared to the worn synchros in the 4-speed.

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1. When I first did my 5 speed, I thought, "hey this slave looks good, I'll use it" Then a week later I'm changing it for a new one. If the slave releases the clutch with little effort and doesn't leak, what's wrong with that?

2.So you loosened the diff and pulled it back and now it looks like the guibo is being pulled to the rear? Just loosen the diff and push it forward again. Loosening the motor mounts will not let the engine move forward or back. Be sure to check your driveshaft alignment. Is the guibo deformed the same top/bottom and left/right? if it's not the same all the way around then you have an alignment issue, if it's the same then it's being pulled/pushed. Any of these scenarios are not good for the guibo.

3. I had a mystery vibration at around 3200 and it went away when I added an exhaust brace at the rear of my trans.

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Thanks for the response...I think my point of the guibo/diff might sound 180 off...I had to move the diff forward (to the front of the car) to the stops and it is still pulling a little on the guibo. It looks like this symbol "~" only verticle (but only slight...not that exaggerated). I'm almost guessing that the driveshaft is a tad too short...it all came from a 2002 that had the conversion done (maybe its due to the subtle differences in our cars).

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Thanks for the response...I think my point of the guibo/diff might sound 180 off...I had to move the diff forward (to the front of the car) to the stops and it is still pulling a little on the guibo. It looks like this symbol "~" only verticle (but only slight...not that exaggerated). I'm almost guessing that the driveshaft is a tad too short...it all came from a 2002 that had the conversion done (maybe its due to the subtle differences in our cars).

constant flexing will almost certainly cause premature failure, not to mention imparting a "pulling" load on the bearings inside the diff and trans that they're not designed for.

Wouldn't want to drive the car this way for any extended period, but if you want to eliminate the distortion in the guibo temporarily to see if it's imparting a driveline vibration, you could shim the guibo with washers between the guibo and the driveshaft flange (just make sure you mic the washers to insure that they're all the same thickness).

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you could shim the guibo with washers between the guibo and the driveshaft flange (just make sure you mic the washers to insure that they're all the same thickness).

I dismantled a car that had 3 washers per bolt to correct for a bad shortening job.. But it had no vibrations.

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The 320 style throwout has a large leverage ratio, so

it's not unusual to have a pretty darned light clutch

with the conversion.

Never checked to see what diameter master the 320 uses...

probably should one of these days.

t

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Thanks for the responses guys...never crossed my mind to shim the guibo...I might just give that a chance (and I'll certainly check thicknesses on the shims).

I drove the car home and around a bit (probably 25 miles or so) without hearing any indications of problems, I even got it out on the interstate for just a couple of miles to see if I had any driveline vibrations...went up to 80...had none, so the driveshaft is good/well balanced. The shifter handle did vibrate quite a bit at 75ish, but I think that was induced from the slight engine vibration that I'm assuming reared its ugly head since the aluminum flywheel doesn't dampen as well as the stock unit.

The theroy about the larger t/o bearing makes some sense...but I am still a little confused. I'm running the standard 215mm clutch w/throw-out bearing and compared to the removed 4-speed unit, the new T/O bearing looks like it is the same size in diameter, however only a tad shorter in length (by about 1/8" or so if memory serves me correcty). And since I'm running essentially the stock clutch (disk and pressure plate) wouldn't that mean that I should expect the same level of feedback as I had before? Maybe the surface area of the piston in the old-new slave is larger than the 4-speed slave and thus requires less effort to push due to greater hydraulic volume? I'm not sure...didn't have any issues driving it around today so I don't think I'm really going to worry about it for now...Turner Motorsports has slaves at $29 and change so I might just pick one up for piece of mind.

I think I'll try to get her shimmed up tomorrow and see what happens from there...at least I won't be as worried about the guibo failing on me at speed!

Cheers,

Bill

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no, take a look at the way the linkage on the throwout itself works.

The 2002 version has an arm, a pivot, then the bearing. The pivot's

central (more or less) to the two ends, (it might give some leverage

to the bearing but not a lot)

The 320 version has an arm attached to the slave, the throwout, THEN the

pivot. The slave's at LEAST as far from the bearing as the bearing is from

the pivot, so there's a 2:1 mechanical ratio right away. It might even be more.

So you move the bearing less far, with more force- so the spring pressure

fed back from the clutch is significantly reduced.

... and I have no idea what the master and slave diameters on

a 320 are. The 2002's 3/4" for both, I seem to remember...

t

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Update:

This morning I took Betty back to the auto hobby shop to check out the guibo and driveshaft. Initially I didn't notice any vibration (probably due to the rough roads around here and the myriad of noises the car makes...beauty rings and other pops and squeaks in the interior); however this morning as I was driving through the neighborhood I did notice a slight vibration between 15 and 20 mph. So my theory of getting the driveshaft perfectly aligned the first time was not correct.

After a worrisome trip back to the shop (about 20 miles or so) I put her back up on the lift and proceeded to disconnect the tranny support and rear guibo (and csb to help remove the guibo). My fears did not come true...the guibo was indeed intact and showed no signs of premature fatigue (with less than 50 miles on it I sincerely hoped it wouldn't)...whew!

I ended up having to shim the guibo as the engine did not want to budge to help me close the gap between the guibo and the driveshaft. I ended up with one shim on each side of the guibo between the flanges (that way there isn't any offset in either direction and allows the guibo to be centered). I opted to do it this way because it allows the locking nuts to be fully engaged...with two shims (which was the required number to close the gap) on just one side the bolt doesn't quite make it to the pinch part (end) of the brass nut.

While I was figuring out that little piece of information, I also checked the driveshaft alignment (while the guibo wasn't mated from the d/s side). Using a screw-jack I fine-tuned the height of the transmission so that the space between the d/s flange and the guibo was equal all the way around. So now that the transmission and the front part of the d/s was matched what about the second half of the d/s?

Well, when i first installed the d/s I eyeballed it and used a yard stick as my straight-edge. This was a futile attempt at best, but I did get it pretty close. What I did today was to get a piece of fishing line (any string will do) and tied one end around the end of the u-joint near the diff to where the string was in the exact center, parallel to the ground (gee, writing this out is a lot more difficult than actually doing it...) and tied the other end through the hole in the guibo (centered level as well) and pulled taut. Essentially that gave me a straight line, down the center of the driveshaft, to adjust the csb for the correct position.

Well, I drove her home and didn't (again) feel any vibrations and there are no weird noises to speak of (well, maybe the exhaust dinging against the rear subframe when I kill the engine...but that's about it). She definitely 'felt' better and there is now no distortion of the guibo. I'll keep my fingers crossed for the next few thousand miles and hopefully all will be in good order...

Cheers!

bill

P.S. Is the engine 'tired' if I can turn it over by hand using the flywheel...and the spark-plugs are still installed? Yeah...thought so as well.

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Dude my car suffering from all the same symptoms. I did a 5 speed conversion. Aluminum flywheel. The result is premature guibo wear 200 miles and the guibo looks like pit bull chewed it up and spit it out. super soft clutch pedal but clutch works fine. guibo rubs on shift shaft housing guibo has a ton of deflection.

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Wow, sounds like mine was not as extreme as yours...

Deflection...did you move the diff to help compensate? How much deflection are you experiencing? I'm pretty certain that the deflection contributed to the premature wear on your guibo...wow, only 200 miles...that sucks! Did you adjust the rear height of the transmission to get the output flange and the driveshaft flange parallel? I thought I had it pretty good at first but when I checked it (by trying to install the shims...it allowed me to get a better 'feel' of how far I was off, rotate the driveshaft and see if the space between the flange and the guibo is constant all the way around). I think after I re-installed everything I might be of by like a gnats butt hair or something...it's a lot better than it was and I still have a little bit of room left to shim it up if need be.

As far as the guibo hitting the shifting rod/support...something doesn't sound right. I know the clearance is pretty tight on mine...maybe there is a bushing or seal on the shifter rod that might need replacing, hopefully someone way more knowledgable than I can pipe in and help you out.

Cheers,

Bill

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