Need to find a little more adjustment in my Master to totally dis-enguage the clutch.

[BillZ260]

THis is what I'm running.

 

T-5

Ram blowproof flywheel

Ram 10.5" cluth and pressure plate

New 3/4" Tilton Master

New Tilton HTOB (Adjusted half turns untill the bearing spun freely with the trans bolted up to the motor w/ flywheel/clutch installed)

 

Everything is bled.

 

With the engine running, I can not place the car into 1st or reverse, at all. But If I put the car into 1st or reverse, THEN start it up w/ the cluth in it barely wants to move.

 

I checked the pushrod to the master, looks like it's adjusted all the way out, at least as far out but still able to have the lock nut fully enguaged w/ the rod, So maybe one more thread out would be ok, but I don't know if I like that or not.

 

I tried pulling the rubber stopper off the clutch floor stop, still the same scenario above. I could cut off the stop and place the rubber directly on the floorboard, but that should be a last resort.

 

Any other thoughts? I could buy the 7/8" Master and replace, but only want to do that if it's absolutly necessarry. Seems like it's really close, just not quite enough to be adjusted right.

 

Thanks!

[V8ZRACER260Z]

I ran a Quartermaster Throwout bearing and I had to go with the larger Master cylinder to get the throw needed. NOTE make sure you do not over travel the Throwout bearing as it will rip the O rings in it. The Tilton may have a internal mechanical stop to prevent this, but the Quartermaster did not (Learned the hard way). I installed a mechanical stop on my pedel travel to prevent this. Also don't crank the car without the ground attached as the braide line to the Bearing do not like that, another learning curve by being impatient.

[blueovalz]

This is almost the identical parts I use on mine (Ford though). Do you know where the HTOB sits currently in regards to it's range of movement. If it is at the end of being fully extended, then you may be running out of travel. For me, the adjustment phase was a PITA. I ended up spinning the threaded adjustment tube from under the car (through a couple of holes in the bell housing) while all of the stuff was assembled, but once adjusted correctly, I fell in love with this product. On one hand, you'll need to have it far enough forward to fully disengage the clutch, but on the other hand you need it far enough rearward to allow for clutch wear over time.

 

If it is on it's stop (fully compressed), then I don't know what the answer would be, but I do know you'll have problems later:

 

I found that as my clutch disc wears, the fingers that are used to disengage the clutch (fingers on the pressure plate) move inward toward the transmission. IF the HTOB was adjusted just off the stop (fully compressed), the the bearing will not be allowed to move any further rearward to compensate for clutch wear, and you'll end up with the clutch partially disengaged with the foot completely off the pedal. I found I had to move the HTOB rearward (on the threaded adjustment tube) so that at full pedal movement, the clutch was fully disengaged. At this point the HTOB will be fully self-adjusting as the clutch disc wears and becomes thinner (the the fingers of the pressure plate move closer to the transmission).

[Pop N Wood]

Not sure about your exact set up, but I destroyed an HTOB on my set up when I over extended it. When I ordered a replacement HTOB, they sent me the installation instruction that they failed to send the first time out.

 

The instructions said I needed to measure the distance from the back of the bellhousing to the clutch pressure plate fingers and make sure it was within some range. My specific set up needed a half inch of spacers behind the HTOB to give me enough range to ensure the clutch would disengage.

 

here is a picture to show you what I had to measure

 

http://erareplicas.com/427man/clutch/conc_to.htm

 

so maybe you need spacers between the HTOB and the trans body.

 

The spacers were not anything simple, but machined pieces that pretty precisely centered the HTOB.

[BillZ260]

Thanks for that note. I remember taking those measurments, and calculating everything out. I think once I put the assembly all together, I was off 1 rotation or something on the adjustment of the HTOB. I remember unbolting the trans, turning it in 1/2 turn, rebolting the trans and repeating untill I could turn the HTOB. So it should be ok as far as adjustment goes.

 

I'll dig up my instructions and notes, hopefully my measurments are still in there and we'll see what the Ram Clutch needs and the HTOB will supply

 

I think I needed a brain nudge, hopefully this will come out to an easy solution. But worst case is a new Master I think.

 

EDIT:

 

Looking at those diagrams again, the collar of the input shaft housing is threaded on for the tilton set, where the HTOB threads onto it supplying the height adjustment. So I don't think a spacer would be appicable with this set up. Thanks for the comments though, got me to thinking, and I'll check some things and let you all know how they turn out.

[BillZ260]

Had time to dig up my measurments but didn't have time to decipher I'll play tonight.

[BillZ260]

Re-read everything last night, looks like my HTOB is too close to the cluth fingers, but that should only affect the clutch once it starts to wear. Went out, jacked up the drivers rear lower control arm, stuck the Z in 1st and slowly enguaged the clutch while trying to rotate the wheel by hand and it didn't free up at all.

 

I'm almost convinced that I should have bought the 7/8" Master. I'm going to call / email the tech's at Ram and Tilton today and see what I can come up with.

 

I know the Piston Diameter, but I don't know the throw, if I can find that out I can figure the total possible fluid movment for the Master.

 

I know the HTOB piston will move MAX .700, but I don't know the piston diameter, if I had that I would know how it would move in correlation to the Master.

 

I would like to know what linear movment it takes to disenguage the Ram set up.

 

I think if I gather all this, I'll know a bit better what I need to do to get this fixed.

[blueovalz]

It takes very little movement at the fingers to disengage the clutch disc (I'm thinking about .060"?) which puzzles me how this would not work. I'm using a 3/4" Tilton on a McLoed HTOB on a Ram (long style) pressure plate, and have never had an issue other than initial adjustment. Can't wait to hear how you've resolved this issue.

 

The HTOB's cross sectional area can be calculated by comparing the amount of movement at the HTOB as compared to the amount of movement at the MC. If the MC moves 1" for a 1/2" of movement at the HTOB, then the HTOB has twice the piston area of the MC. In your case, a 3/4" master cylinder's 1" stroke, moving a HTOB 1/2" at the clutch would mean the HTOB's effective bore is ~1 1/6" in diameter. Increasing the MC bore to 7/8" would give you a 68% movement ratio rather than the 50% movement ratio at the HTOB.

 

That example does not represent a realistic rato between the MC and HTOB, but does show that you can determine the HTOB's piston area.

[BillZ260]

I'll see what the tech's have to say. I'll try to get some sort of feeler guage in there to see where it's setting. It may be that it isn't bled well. I didn't bleed it but the guy that did seemed pretty sharp... will see.

[BillZ260]

Added at least 1/4" of throw to the peddle / piston movment, still nothin. I think that is as much as I can get out of this cylinder.

 

SO short of some small stupid thing I am some how missing that the tech's point out, looks like i'll be needing a 7/8".

 

Tried to get something in there to "feel" the gap between the HTOB and clutch fingers and nothin happening.

 

Who knows, with all these little things going on w/ the car, leaks and this and that's. I may end up pulling everythign out checking it thouroughly and seeing what's what.

[BillZ260]

Ram Tech states:

 

"Travel needed on the new discs is about .400-.500, I have no tech info on

the tilton master or bearing."

 

So based on how far the 3/4 CAN move the HTOB, i'll need to go bigger. Again, HTOB max movment is .700.

[BillZ260]

Ram Tech states:

 

"Travel needed on the new discs is about .400-.500, I have no tech info on

the tilton master or bearing."

 

Again, HTOB max movment is .700.

 

Looking at these drawings: http://www.tiltonracing.com/content.php?page=hydro the piston diameter is 1.26 or 1.40.

 

So worst case scenario the 3/4 (.75) master CAN move the HTOB 1/2" for every 1" of pedal movment. I need to get specifics on piston diameter on MY HTOB, since I don't think its actually represented in those drawings.

 

IF i have 2" of throw on the peddle (anyone know how lone the tilton master throw is?) then I should be able to move the HTOB slave almost 1" right? Which should be enough..... Will see what the Tilton guy says...

 

ECH!

[BillZ260]

1 week and nothing from Tilton.

 

After some figuring and pondering, I've ordered a 1" master. Should ensure that I can adjust it to the throw I need w/ room to spare. I hated to think about ordering a 7/8" and it not quite be there so the 1" it is. Should be able to get it installed next week and adjusted. I'll let you all know how it turns out.

[blueovalz]

Ram Tech states:

 

"Travel needed on the new discs is about .400-.500, I have no tech info on

the tilton master or bearing."

 

Again, HTOB max movment is .700.

 

Looking at these drawings: http://www.tiltonracing.com/content.php?page=hydro the piston diameter is 1.26 or 1.40.

 

So worst case scenario the 3/4 (.75) master CAN move the HTOB 1/2" for every 1" of pedal movment. I need to get specifics on piston diameter on MY HTOB, since I don't think its actually represented in those drawings.

 

IF i have 2" of throw on the peddle (anyone know how lone the tilton master throw is?) then I should be able to move the HTOB slave almost 1" right? Which should be enough..... Will see what the Tilton guy says...

 

ECH!

 

 

This is very puzzling. I wonder if the .4-.5" (I can only assume) is at the MC? The reason I say this is that once the TO bearing makes contact with the PP, it takes very little movement to release the pressure on the disc for a shift or release (usually less that .1" at most).

 

The 1.26 and 1.40 diameters are for the inner hole of the HTOB. I am making an assumption here (looking at the HTOB in my hot little hands) in that the piston is actually a donut configuration, so you'll have an ID and and OD of the piston itself, and the cross sectional area must be determined from this figure (the ID and OD of the bore, not the dimensions shown in the drawing. If you indeed have a too small a MC with the 3/4", then consider the "feel" of the pedal, and consider the change in this feel by switching to a 1" MC, which will be almost double the pedal pressure you'll have with the 3/4". Being you're not releasing the disc at the current state, you really don't have any reference "feel" to go by to see if doubling the leg work will be appropriate.

[BillZ260]

I wondered if the piston was a doughnut shape, but couldn't remember. So I can assume that it probably 1" or less surface area considering the hole is to allow the tip of the input shaft to protrude through, right?

 

I do understand the the feel of the pedel should feel 'lighter' with a larger master and the basics of hydraulics.

 

Right now with the 3/4" I have it adjusted to MAX throw. The peddle has resistance with in probably 1/8" in of movment, so basically it's pushing the HTOB throughout the entire swing, right? It's basically Rams clutch that is 1 step above stock, so the peddle isnt' really all that heavy already.

 

With a 1" Master, it should feel lighter, the amount of movment will be reduced by around 30%. (Can I assume that?)

 

Thanks for the insight Blue, parts will be in on the 18th, we'll see how it goes. I REALLY want to drive this car!

[blueovalz]

In you situation, you'll increase the pressure at the pedal by about 77%, and the stroke will be close to 1/2 of what it was with the 3/4" MC.

[BillZ260]

Maybe I don't understand basic hydralics?

 

AH! DOH. I get you. It will be more like pressing directly on the clutch fingers, where the smaller piston takes less effort but more movment.

 

1/2 the distance is fine, since it's moving almost full peddle stroke under pressure and not fully releaseing.

 

EDIT: this made me want to know more about what's happening. Found this site by doing a "basic hydralics" search http://www.free-ed.net/free-ed/MechTech/hydraulics01/default.asp

 

Below are what I think are the differences I should see between the 3/4" and 1" master assuming the fingers require 50Lbs of force and a slave piston diameter of 1". The follow what you noted above Terry, thanks for making me truely understand!

 

Dia / Piston Area / Force / Distance

(0.75) / .441 SqIn / ~28lbs / 1.77" : 1" (.680 to move slave .400)

(1.00) / .785 SqIn / ~50lbs / 1.00" : 1" (.400 to move slave .400)

 

I guess i can measure the peddle arm assembly, it's pivot point, and arm actuator location and really figure out what this should take. I may just do that to help future folks know what it SHOULD take to move their slaves.

[BillZ260]

This is very puzzling. I wonder if the .4-.5" (I can only assume) is at the MC? The reason I say this is that once the TO bearing makes contact with the PP, it takes very little movement to release the pressure on the disc for a shift or release (usually less that .1" at most).

 

 

Re-reading this thread and this is confusing. I would expect the Clutch mfg to quote the distance at the pressure plate.

[blueovalz]

It's also interesting to see the dimensions in this string in that my 3/4" MC on my McLeod HTOB works great, but with your combination, it requires a significantly larger MC. So it appears that..

1: Your PP requires much less pressure (50 lbs) than mine (hundreds of lbs). Just to hazard a guess here, but with that low release pressure you quoted above, I'll bet you do need the extra movement compared to my high pressure/short movement), and...

2: Your HTOB piston area is much larger than mine.

[BillZ260]

I made up the 50 lbs, i have no clue what the specs are for the pressure plate fingers. I just used it as constant to show the new formulas i learnded, but it was also kind of guessitmated based on the currently LIGHT peddle feel.

 

What type of clutch are you using? This Ram that I have is a upgraded stock replacment, so I didn't expect a heavy clutch feel.

 

BUT it is odd that a 3/4 doesn't work for one HTOB when it does for another. Even with different brands, it seems the dimensions of the slave piston would have to be close, say w/ in 10%. But then again, your comment on the heavy vs light fingers kind of makes sence. But I don't know much about clutch variations and how this and that can change depending on what you have.

 

I guess it goes to show that you can there are so many variables when working w/ these types of parts! Every now and again, I find myself saying, "if you'd have gone w/ a built 700R4 you'd be driving your Z!" But then I think, it wouldn't be as fun!

 

It's all about the learning process!!!