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Triumph TR6 - Clutch Slave Pushrod Length?
|Does anyone know the "official" length of the pushrod that |
comes out of the clutch slave? (from the end to the hole where the clevis pin fits)
The one on my 75 Tr6 has been modified and is adjustable via part of it being threaded.
There was a thread last year on this exact same subject...sorry do not recall the title. Have a look back there...something like 4" rings a bell.
I measured mine today and from the tip to the center of pin hole it is 6 9/16 inches.
I don't think mine has been modified at least I haven't in the last 18 years.
Hope it helps
|Aivars-I must be marching to a different drummer. My pushrod is 5.7" from tip to center of pinhole.|
|Ok guys now we have him totally confused. |
Berry what year is your TR mines 72. Looked in all the parts manuals and can't find a difference. Can't find a specific length on the net either. We are out by about an inch and considering the best that slave moves shaft is about 1/2 inch not a chance. I wonder if there were different slave body units fitted?
Might also explain why some of the guys with the spin on filter addition have problems getting the filter vertical?
|Bill-My car is a 71. I have had it for about 20 years. I replaced the slave cyl, but don't think a new push rod was included, so the length I quoted should be from the pushrod that was fitted at the factory, unless it was changed by a previous owners. Just to muddy the waters, recently I changed to the adj.push rod and external spring, like the tr3-4 setup. The reason being there was a lot of discussion about release bearing problems and a groove being worn in the pressure plate by the bearing. It seems the self adj set up allows the bearing to be in constant contact with the pressure plate without enough pressure to spin the bearing when the clutch is engaged. I checked a clutch that had been repaced at about 30k miles and found a significant groove worn in the pressure plate. Using the adj. setup keeps the bearing out of contact with the pressure plate when the clutch is engaged. Another solution is to use a bearing that is spring loaded against the pressure plate and turns all of the time. There is an in depth article on the Buckeye website about release bearing woes.ZZZZZZZZ|
|Sorry Bill, I forgot my name.|
If you have had a TR for 20 years adding to all the other things you have to remember to do in life. "Who am I" is not real high on the list. Been there. Done that.:)
Yah the 4-4A adjustable setup I think works better. Still can't figure that inch.
Never had a problem with clutch other than bleed in 18 till I tossed a thrust bearing on crank.
|Cannot see why a TR hydraulic clutch should be any different than the other few million on the planet. Have personally worked on hundreds of clutches and all hydraulics are self adjusting, w/ just enough residual pressure to keep bearing spinning w/o excesive wear on clutch fingers.Can see possibly creating problems by trying to adjust them. Push rod length does not matter within large limits - the fluid takes up the difference.Peter|
|My brain hurts.................. Seriously, thanks for all the input!|
I've spent a bit of time reading up on all of the clutch woes with the Tr6 - in an attempt to eliminate the troublesome areas of this setup - therefore the question.
What I'll do (I think?) is adjust the pushrod on the "short side" and see what happens?!?! PO had the clutch adjusted so much that it caused thrust washer wear on the engine - that I've since fixed.
Just measured one that sits in the spares bin. 5 11/16" so same length as Berrys' or Bills' whatever his name is:) Mine is also 71.
|Better too short than too long. As I said earlier,will self adjust - only the fluid that NEEDS to return to the master cylinder will do so. Too long, and it cannot self adjust. Peter G|
|Aivars-Any idea why the adjustable push rod was added? Is it possible the PO was having problems getting the clutch to release and thought that lengthening the push rod would help (it won't). Just a thought.|
|I just built a TR6 chassis for racing and had a similar problem. It was to short, so I made an adjustable one also. The inch it was short would not have taken up by the fluids, and it would not have fully disengaged. This was very baffling to us, still is, as this was an overdrive transmission swap also.|
|Charley-You might check to see if the slave cyl is correctly mounted. The mounting bracket is on the front side of the engine plate and the slave cyl goes on the rear side of the bracket. If the cyl is mounted on the wrong side, the push rod would appear to be too short. The OD trans is not a factor. On another note, I have seen a TR6 PI at the historic races at PIR. The car is very well prepared, goes great for several laps, then usually drops out from various mechanical problems. I have seen this happen at least 3 times. The car is owned by Tom Kreger of Vancouver, Wa|
|Very easy to mount slave on wrong side of bracket. It took 3 calls to TRF to make sure they sent me the right slave. The push rod just didn't fit. Had it on the wrong side. It just lloks like it should work that way. Charly, I get to Tacoma in my work on occasion. Would love to see your project.|
I hope you're on the road again. I'am currently trying to get rid of my 'drag' problem. Mine TR is from early '73 and has a pushrod of 5.7". I agree with Peter G. the size doesn't matter. However when you have to much play at the pedal side (worn clevis pin, pushrod holes or pedal hole)it can occur that the pedal is against the stop bracket, but the master cilinder is not at the end of its stroke. In this case you must get rid of all the mechanical play by e.g. clevis pin whith bigger diameter redrilling of the holes or you can mount an adjustable pushrod at the master cilinder side! But beware that the pedal keeps its mechanical stop to the brachet and not intern of the master cilinder.
Hitherto I did all modifications.....but still have a 'drag' problem.
I was having problems with clutch fully disengaging until lately (is that what you mean by 'drag' problem?), After repeated bleeding/rebuild of master and slave, I decided the only thing I hadn't touched was that stupid plastic tube that is the lower half of the tube to the slave, so I replaced it. The car shifts so well now that even my wife can drive it (a mixed blessing I guess). I'd read somewhere that when they get old, they flex too much and use up some of the hydraulic force.
Does anyone know what purpose this plastic serves? Why didn't they just use steel tubing to the slave? If the PO didn't leave me with a replacement, I would have been tempted to eliminate the plastic.
Anyway, good luck with your clutch,
Thanks for all of the measurements. I've adjusted the length of my push rod to about 5.7 inches. I haven't had a chance to try anything out as my body still needs to be installed back on the frame. (hopefully this weekend)
I did however remove all the areas of play that I could find - clevis pin, elongated hole on the clutch pedal.
Mark - I plan also to replace that "sturdy looking" nylon hose that connects the slave to the master. I'm just planning to get a hydraulic hose made up at a local industrial supply place. I assume it is flexible hose because there in engine/trans movement ?
Industrial hydraulic hoses are not suitable for brake oil (mineral based)was told to me. So I have a stainless steel braided replacment, made by a local brake overhaul company. Maybe when you use silicon DOT 5 it is possible to use industrial hydraulic hoses.
Yes, I mean a disengaging problem, next weekend I'm looking futher into the problem, I have information from the Buckeye site that the travel of the clevis pin by the clutch operating shaft arm must be at least 1/2 inch.
|Mark Et Al|
I posted to a thread about 2 years ago about your problem. Off of the old Zimmerman WEB page there was just that situation...expansion of the red plastic line and reducing actual hydraulic pressure to the slave piston....his success was exactly yours Mark. I think it was about 1.5 years ago I suggested a "tech-Tip" thread(s) that could be ongoing and little comments like yours Mark could be added to them. A Tech-Tip thread for: clutch and brake, electrical,tyres (how many times is it asked what size of tyre for a 6?), and the biggy...carb problems,....etc. These tech-tips could even refer back to past threads with a thread name and date.
Go ahead..someone start one.
Why the flexible line instead of a solid line? I would think engine vibration. I would not think for flexing as there would be little engine flex (from torque) way down at the bottom of the engine. I do not think it would be a good idea to replace with solid line but instead flex like Marc suggests. Do not know answer to DOT 5 (or DOT 4 for that matter) and compatability with rubber hydraulic hoses....but must be OK as we have 4 rubber brake lines on our cars now. The simple question is: are hyraulic hoses compatable with a silicone base fluid (DOT 5)?...I presume everone uses DOT 5.
|I have used the purple type solicone brake fluid in my TR3A for 12 summers (over 70,000 miles).|
I changed all the rubber hoses and all seals during my restoration from 1987 to 1990. I have changed the seal kit in the clutch slave cylinder as well as the original style black rubber hose that feeds the clutch slave cylinder.
I still have the same 4 brake hoses on the car that I installed new in 1990. I have spares and one day, I'll have to get around (or rather under) to changing them.
The racers use solid piping where is was originally and teflon lined stainless braided hoses where flexibility is needed. But then, they would never use silicone fluid anyway. If you have to drain the brake fluid between races to work on the brakes, you don't want to have to wait a couple of weeks for the bubbles you entrain into the fluid while pouring it into the master cylinder reservoirs to excape - because you want to get into the next race ASAP !
Don Elliott, 1958 TR3A
|There are two ways to mitigate vibration in lines of a fluid system. One is to use a flex line, the other is a coiled solid line. The TRs went the flex line route while Spitfires (at least the USA spec 1500 cars) went the coiled piping route. I use one of the stainless braided teflen flex lines on my TR6, wife's Spit has the stock coiled pipe.|
As for the DOT 5 stuff, Don has pretty much hit it. It's not a matter of cost cause the really high temp DOT 4 stuff is just as pricey, it's getting all those pesky bubbles out of the system.
|This is a fix I used to stop the clutch drag on my 70 TR6. What I was experiencing was after the car warmed up the clutch pedal would stick close to the floor and then release, causing the car to jump. After checking all the normal causes, clutch master/slave/linkage, I removed the transmission and checked the clearance between the throwout bearing sleeve and transmission housing. My clearance was .004 I felt this was insufficient clearance and may decrease when warmed up causing my problem. I removed the transmission input shaft housing and using a lathe I polished the portion the sleeve rides on. My final clearance was .015 in.|
After doing this procedure the car has been fine for over one year. Previous to this I had two throat bearing failures. Hope this helps.
|Re DOT 4/5 - had mixed results. DOT 5 in my MG was trouble free but on my Jeep, with all new stuff, leaked in a short time (I'd heard this could happen with slippery silicone). With TeResa, she gets DOT 4, same base as 3 with higher boiling point, taking no chances with my baby. Peter|
I modified my push rod also so as to get maximum throw from the slave. This was a mistake. If you don't leave enough clearance between the push rod and cross shaft lever, the throw-out bearing is constantly in contact with the clutch spring. The beaing lasted less than 100 miles like that before I had to replace it. Clutch release was great but the bearing suffered. Ensure that there is sufficent play at the end of the push rod to allow the throw out to sit away from the clutch. Lesson learned the hard way.
ALSO: I use DOT 5 but find a layer of liquified rubber in the reservoir. Is DOT 5 rotting my seals?
Dot 5 is compatable with the seals in a TR. In order to switch from DOT4 to DOT5 it is necessary to replace ALL seals in every place there is a seal in the entire brake (and clutch) system. THIS MEANS EVERYTHING. You see DOT4 (and3)are NOT compatable with DOT5 and if above is not done then yes the seals will turn into gum. I hope this is not your problem Bryn.
|After reading the long and deep article on brake fluid on the Buckeye site, I don't think that mixing the 2 types of fluid would cause any damage. Any glycol left in the system could absorb moisture which would basically neutralize one of the benefits of changing to silicone fluid. The layer of rubber floating in the fluid may be caused by a seal being abraded on a rough spot in the bore of a cylinder. |
This thread was discussed between 16/03/2003 and 03/05/2003
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