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northoceanbeach
03-05-2007, 02:47 AM
Ok, this is like my millionth post on this but I still can't figure it out. But there is progress. I'll start with the history. Keep in mind I am a very, very beginner mechanic here. The most work on a vehicle I have ever done is what I have done to my new(ish) landy.

OK in short summary I bought 1973 SWB. Had towed to house. No clutch pressure. Put in new clutch master and slave. Added fluid. Had pressure. Drove. Noticed cluthc was slipping. Sliiping got worse. Bought and installed new clutch, pressure plate and throwout bearing. The clutch I took out was old, worn down to the rivets. No oil contamination in there. Very dry. FLywheel looked good, but I have never seen one before. CLutch job seemed to go smooth. Took a test drive. Still drovde the saem, still slippage.

!!I think this may be important. When I put in gear and let off the clutch, it doesn't move forward until the pedal is pretty much completely released. It doesn't even begin to roll forwad until the clutch pedal is at the very top. So what I was guessing is that something is keeping the clutch is ever fully engaged.!!

So the other day I bled the clutch in case I had air still in there. And I did, alot of bubbles came out. I also the same day tried adjusting the linkage where the pedal connects to the master cylinder. I then put on a new flex hose.

After doing those three things it got better. It doesn't slip as much, not at all, very noticeable difference. But going up hills it still does slip.

I am kinda encouraged that it got better. But I have no idea what I did that helped. Or how to make it stop slipping completely. Any ideas?

A neighbor came out, and he know a bit about cars, but said he never really worked on a hydraulic clutch before but he mentioned these possible causes. I'll throw them out there in case they sound likely.

1. I got sold a too thin clutch

2. the slave cylindar pin is too long and always holding the clutch arm a little off the flywheel. He said I could maybe take the slave off and put spacers so it is held a little farther off the transmission.

3. there is always a little pressure in there. He said it can happen when cable clutches that there is always some tension.

What would you guys try? Think I should bleed more that there may be some air still in there that is hard to get out? It looks like the master linkage is adjusted right, It appears to have free play. THe bolts are pretty close to the tip of the master cylinder pin and they are tightened around the top of the pedal. I really don't have any other ideas.

As always, thanks for any help.

Clive
03-05-2007, 11:26 AM
You seem to have tackled most things so this sounds like a frustrating mystery because the clutch is pretty straightforward (having had the one in my 73 SIII in and out about five times for various, non-clutch related issues).
To me it sounds as if your clutch is not fully engaging for whatever reason. It has to have a straightforward mechanical solution so it would appear that short of someone offering that going back to basics may be the only way to track the fault down:

1. Is it the correct clutch/pressure plate and combo? What diameter (I recall there may be a couple, 9" and 10 "??)? Someone else may be able to shed more light on that.
2. Was the clutch put in the correct way around? (shouldn't work at all if it wasn't!).
3. Was the clutch aligned correctly using a clutch alignment tool or equivalent before tightening the pp? (again, this would be an unlikely cause as the the shaft wont really fit if it is not...)
4. Torqued everything properly?
5. Is the slave cylinder rod the correct length/right way round?
6. Is the lever for the thrust bearing in the bell housing set up correctly and able to move the full distance (ie not being blocked by something)?
7. Is pedal height and push rod on master cylinder correctly adjusted. If these are severely out of whack it would have the effect of riding the clutch (ie, it would slip). The push rod here is critical, and awkward as hell (as you probably discovered weeks ago).

Based on what you have done already 6 or 7 would appear the most likely. Can you post any photos of it? What about the measurments of the rods and clutch settings?
Why was there air in the system after you bled it? Where is it leaking in? Although that would make it difficult to dis-engage the clutch, it would not cause it to slip, but you'd crash your gears...

scott
03-05-2007, 01:44 PM
i am feeling your pain (slippage). i'm in the middle o a clutch job myself.

- there are 9" an 91/2" clutches and prs/plt. you can't/shouldn't mix these sizes. use a 9 w/ a 9 or use the 9 1/2 w the 9 1/2.

- adjust the lingage below the slave so that you get the right travel and when at rest the t/o bearing is applying no force against the prs/plt.

- the dude who did the last clutch job on mine forgot to remove the spring retaining clips. mine has 3 on the back side of the prs/plt and they're red. if not removed after install the full force of the prs/plt won't be felt by the clutch slippage may occur, clutch life will be short.

- you should always have had the flywheel turned

- i'll post pictures tomorrow or wednesday.

scott
03-05-2007, 08:16 PM
http://www.roversnorth.com/forums/attachment.php?attachmentid=72&stc=1&d=1173147186 this is my old prs/plt the arrows point to the clips that were never removed
http://www.roversnorth.com/forums/attachment.php?attachmentid=73&stc=1&d=1173147186 here's a close up

Clive
03-06-2007, 06:59 AM
SIII 1973. I installed a new clutch and pressure plate 1 y ago when I did a bunch of engine and transmission work and never removed any "tabs" from the pressure plate...the clutch seems to work fine, no slippage....
It doesn't say anywhere in the Green Bible or the Haines manual that you should remove anything from the pressure plate on installation, and not being a swami I did not. Where can I find out more about this and do I need to remove my transmission (again!) to get at the pressure plate and remove these "tabs" from the pressure plate springs? That would be a real bummer. My transmission and I do not get on well.
Are all pressure plates the same (SII, SIII etc OEM, Borg&Beck?)?? Help. Many thanks.

Dav1550
03-06-2007, 07:41 AM
Not sure if this would relate...... I had an initial problem with the clutch slipping after a rebuild on an SIII

To be more precise the clutch plate was not fully engaging..... It would start out just fine but after clutch peddle was depressed and released a few times the clutch master cylinder was not fully releasing the pressure on the line to the slave...... Hence the clutch would start slipping in short order once underway.


Suspect that I've got the adjustment off where the peddle attaches to the master cylinder.... But was able to get it sorted for now by adjusting the clutch peddle 1" higher than what the manual call for.

Dave

jp-
03-06-2007, 08:36 AM
http://www.roversnorth.com/forums/attachment.php?attachmentid=72&stc=1&d=1173147186 this is my old prs/plt the arrows point to the clips that were never removed
http://www.roversnorth.com/forums/attachment.php?attachmentid=73&stc=1&d=1173147186 here's a close up

Scott,

Those are assembly bolts for the pressure plate. Do NOT remove them. That is why they have locking tabs on them.

If you wish to test your pressure plate to ensure that is working correctly, place it on a flat surface (with the side up as shown in your first photo) and stand in the center of it. I weigh 185 and with a slight bounce, the pressure plate will spring open and then closed. So basically, a pressure plate in good working order should provide in the neighborhood of 200lbs of resistance.

jp-
03-06-2007, 08:41 AM
..... It would start out just fine but after clutch peddle was depressed and released a few times the clutch master cylinder was not fully releasing the pressure on the line to the slave...... Hence the clutch would start slipping in short order once underway.

Dave

Dave,

This is an excellent observation, and was pointed out in the first clutch slipping thread. Although, my experience was with a CV master cylinder for the brake system. If this is the problem it should be very easy to check.

Northocean,

To test this, pump the clutch pedal up several times and release. Wait about 30 seconds, then open the bleed screw on the clutch slave cylinder (you might want to have a hose on the bleed screw). If fluid blasts out the bleeder, your master cylinder is not realeasing the pressure.

scott
03-06-2007, 12:03 PM
jp

this is a quote from the mfg of the prs plt i just installed

"Certain coil spring cover assemblies are fitted with despatching staples or spacers, normally painted red, between the levers and cover pressing, these should be removed as the cover assembly is bolted up to the flywheel. During cover assembly removal from the flywheel spacers should be simarly replaced to avoid the mounting bolts leaving the flywheel while still under pressure." A.P. Borg & Beck

the pictures of the old ain't red but on my new one they are. i read this to mean put on the prs/plt remove the spacers and put 'em back before removing the prs/plt next time. i think the spaces rmoved increase the pressure on the clutch and therefore hold tighter.

jp-
03-06-2007, 02:53 PM
Scott,

The spacers are not generally used on diaphragm type pressure plates, only on borg & beck types and long finger types. The Rover one is a diaphragm type.

The spacers go between the fingers (lever arms) on the other types. You should not have to unbolt anything to remove any spacers (i.e. spacers should not be bolted on). These spacers are only removed (on the two types mentioned above) when the pressure plate is tightened onto the flywheel. If they were not in place, the mounting bolts wouldn't be long enough to grab the flywheel.

http://www.competitionplus.com/03_25_2004/clutch_univ2.html

jp-
03-06-2007, 03:03 PM
jp

"Certain coil spring cover assemblies...

Diaphragm types don't use coil springs. Only the borg & beck and long finger types use coil springs. See the above link in my earlier post.

scott
03-06-2007, 03:13 PM
jp

i left 'em on 'til i had the prs/plt bolted on. mine is a 9 1/2" Bork & Beck. i haven't put the tranny back in yet but i'm inclined to leave the spacers and he bolts that held them in off per B&B's directions

jp-
03-06-2007, 04:22 PM
Borg & Beck is a manufacturer of pressure plates, as well as a specific type. You may have a Borg & Beck made plate, but if it looks like the one in your photo, it is a diaphragm type.

You don't want to remove those bolts. You really don't want to remove those bolts...

CliftonRover
03-06-2007, 06:27 PM
Just to reiderate what everyone else is saying, make sure your pressure plate is still good, if the clutch feels light this is probably your problem. the pin going into the slave cylinder is easily adjustable ( atleast on my series IIA's). The last bit of advice is to look down through the top hole on the bell housing and make sure your throwout bearing is seated and that when your off the clutch, you should be able to have a tiny bit of play forward and back on the throwout bearing.

scott
03-07-2007, 10:17 PM
clive thanks for pointing out that veiw port on the top of the bell housing.

jp here are those new p/p pics

http://www.roversnorth.com/forums/attachment.php?attachmentid=74&stc=1&d=1173327314 http://www.roversnorth.com/forums/attachment.php?attachmentid=75&stc=1&d=1173327314 http://www.roversnorth.com/forums/attachment.php?attachmentid=76&stc=1&d=1173327314

Clive
03-08-2007, 07:35 AM
Just to ensure credit to the right guy the view port into the bell housing was CliftonRovers idea...but this is proving to be a very useful thread and I have learnt a whole bunch about clutches on series trucks and mine must be the diapram type (no tabs to remove). Meantime I hope NorthOceanBeach is making progress resolving his slippping clutch...

scott
03-08-2007, 07:49 AM
oh yea i almost forgot, how's it going northocean? i didn't me to highjack your thread.

i'm thinking maybe red clips removed but the bolts that held 'em reinserted. the yellow arow is pointing to a piece (tab) that looks like it should be bolted down. jp, any one else, what do you think?

jp-
03-08-2007, 08:28 AM
Scott,

I've never seen those tabs painted red, but I'm pretty sure that they're supposed to be there. I think I've got an old plate laying around that I can check later today or tomorrow.

Here's another clutch link for you.

http://books.google.com/books?id=Dp_LUwqIW7sC&pg=PA484&lpg=PA484&dq=diaphragm+pressure+plate+spacers&source=web&ots=vtejBCN2xN&sig=RspeYiUJesOgAzUs2C39gCA1ue8

northoceanbeach
03-09-2007, 03:09 AM
I hope I am too. Here's the latest development.

My neighbor said that it really seems that something is keeping the clutch just a little diengaged. He recommended that I undo the bolts on the slave cylinder and if it pushed itself off as I undid the bots that would be a sign. So I undid the bolts a bit and the slave did push away. I can apply moderate pressure and push it back in place but it does feel like it's pushing. Does this make any sense? And if so what should I do about it.

ALso does the series 3 have a hole to look into see the throwout bhearing? I don't remember seeing one when I put the new clutch in, but I also wasn't looking for one.

Clive
03-09-2007, 06:52 AM
Yes, there is an inspection cover on the bell housing just infront of the gear stick. Shine a flash light down there and you can see the clutch operation when it is depressed and released.

scott
03-09-2007, 07:38 AM
north

the length of that rise you got when loosening the slave, can you shorten the linkage below the slave by the an equal distance?

northoceanbeach
03-09-2007, 11:18 AM
How would you shorten the slave linkage? I already have the clutch master linkage adjusted so there is free play and I thought that the series three slave has no adjustment.

Clive
03-09-2007, 11:26 AM
My SIII has no adjustment capability on the slave rod. Can you measure it or photograph it?

northoceanbeach
03-09-2007, 11:42 AM
Yeah, I can go out today and snap a few. I just don't get what would do this. Maybe it's not releasing pressure so the slave is always pushing the pin a little or maybe the pin is too long.

scott
03-09-2007, 11:45 AM
sorry you iii ers. mine's a iia and my slave rod is adjustalbe. i can post a pic tonight. north did you get your view hole openned? could your throw out assembly not be seated? it seems it'd have to be that or maybe your clutch pedal return spring? would the wieght of a clutch pedal be enough to push the master cylinder piston enough to compress the fluid enough to push the slave cylinder piston enough to move the linkage enough to partially compress the diaphrm style spring which i hear takes ~200 lbs to full compress?

jp anymore thoughts on the red things on my new diaphram style pressure plate, the instuctions to remove 'em and your thinking they should stay?

scott
03-11-2007, 09:58 AM
the iii's don't have this linkage? http://www.roversnorth.com/forums/attachment.php?attachmentid=92&stc=1&d=1173624689

as for the red clips. i figured it out. i took 'em off the old one to see what they do and jp was right, you don't want to remove 'em. the pressure plate separated from the diaphragm and casing. as for 'em being painted red, well thatís probably just a cruel joke perpetrated by a bored assembler at the plant meant to mess with the mind of a guy who tends to over think stuff

jp-
03-12-2007, 11:04 AM
Scott,

Sorry it took so long for me to get back to this thread. I couldn't find my old pressure plate, but yeah, you want to leave everything as it came. They shouldn't have painted the tabs red; probably ran out of black paint.

jp-
03-12-2007, 11:15 AM
By the way,

I'm thinking of changing my comment below to read:

-There's nothing harder than convincing someone who is certain that he's right, that he's wrong.

jp-
03-12-2007, 11:20 AM
Moderators:

Can I get some more characters for my signature field? It only allows me 150, and I'm at the limit.

Can I buy a vowel???

scott
03-12-2007, 12:26 PM
initially you may not have convinced me that i was wrong but you did stop me from puttin that tranny back in. and it was you saying that you were going to go look for an old p/p that had me saying to myself, "hey i got one, why don't i just take it apart..." and anyway, the red clips are in the tranny is in, the doors seats and floor boards aren't but i'm having fun driving it and that what counts. so did north's stop slipping?

jp-
03-12-2007, 12:47 PM
Scott,

It's all in good fun. I just hate to see people get themselves into more trouble than they really need to. So I guess you could say I'm against self-torture.

northoceanbeach
03-14-2007, 03:57 AM
Well, I would like to say that I have progress but I don't.

Here's what I did today though. I unbolted the slave and put the washers on the other side of the bolts to try to see if spacing it back might help. It did nothing.

But I noticed something on my test drive today. I have this loop that included a couple small hills that I go on every time I try something new. The hills are where I really notice it. Well on the beginning of the drive it seemed to not be slipping. And I think it has been like this on every drive. But the second half of this short 10 minute drive it stated slipping. I could be imagining things, but it really didn't seem to slip at first, but then it started.

I really am out of ideas. I did take the floor plates off and the flywheel plate but mine doesn't hav e a hole to look down into to see if the throwout is seated right. But I there is a weird hole on the top left of the transmission. And it doesn't look exactly right. I'm not sure. On the top left there is a circular hole on the back of this spring looking think, and it looks like it was cut there, it's not perfectly circular. I don't know what this particular part of the transmission is, but I'm just trying to throw everything I notice out to you guys, because I don't know, maybe something I think nothing of is significant to someone with more experience. I'm starting to think I can't do this, I really can't imagine at this point what it could possilbly be.

Hormel
03-14-2007, 11:14 AM
Does the hole on the left side look like the one in the upper left this picture? It looks hacked out on my case also, which i came across while replacing the slave cylinder. I believe there is a castle nut on top of a spring there. I was wondering if it had been knocked off to install a different transmission later, but I have no idea what it is there for.


By the way I am a new user. Great site!
John
1967 2a 109 5 Door Station Wagon

jp-
03-14-2007, 01:20 PM
North,

Did you check the clutch pressure, as indicated in the beginning of this thread? You never mentioned if you did. We can't move on to new ideas until you have gone through the first suggestions.

By the way, I think you will have to remove your shifter to get to the access hole, but it isn't tough.

northoceanbeach
03-14-2007, 02:11 PM
Ok, you're right sorry. So here goes.

yes it does look like that hole, but mine is smaller, about the size of a dime.

I called the place I got the parts from and they said that the pressure plate and clutch are the right size. And I did match them up before I put them in. The pressure plate looked a little different but same size.

The clutch is in the right way. The side that has the stuff sticking out is toward the trans. The flatter side I put towards the flywheel.

I used an alignment tool and it all slid in nicely.

Can't say that it's all torqued right. I had no torque wrench, I just tightened it about how I thought it felt when I took it off. Really tight, but I could've done it tighter.

I think the slave is the right way round. Where the two metal pipes connect on the back, one side is at a 30 degree angle, that side I put on top and it connects to the bleeder.

I don't know if the lever for the throwout bearing is being blocked by something. I hope not. I'll try to remove the gearstick and look down in there.

The pedal height seems good. It's about half an inch lower than my brake pedal and it sure seems to have freeplay. I originally thought that it had something to do with the master linkage adjustment, because mine is hooked to the very tip of the push rod, but I've moved it front and back and it slips no matter what and I do have that freeplay.

As for pressure, I don't know how much should squirt out but once I get the bleeding under way I pump the pedal three times and then hold it to the floor. Unscrew the bleeder bolt and it squirts out pretty good, not a whole lot comes out each time, maybe about a tablespoon full, but it shoots out pretty good.

jp-
03-14-2007, 03:14 PM
As for pressure, I don't know how much should squirt out but once I get the bleeding under way I pump the pedal three times and then hold it to the floor. Unscrew the bleeder bolt and it squirts out pretty good, not a whole lot comes out each time, maybe about a tablespoon full, but it shoots out pretty good.

I know that if you hold the pedal down fluid will rush out, what I want to know is if you pump the pedal up three or four times and RELEASE it, then open the bleed screw; does fluid spray out then?

northoceanbeach
03-14-2007, 03:23 PM
Oh, ok, I didn't get it, I'll try that. Thanks.

TSR53
03-14-2007, 03:43 PM
By the way I am a new user. Great site!
John
1967 2a 109 5 Door Station Wagon

Welcome aboard to the forum, glad to see you sign up and post :thumb-up:. Your first submission included a photo too, schweet!

ps thanks for the kudos on the site...:o

LaneRover
03-14-2007, 08:04 PM
Just thought I would throw a question out that I don't know the answer to. Is there a chance that the clutch actuating arm is the wrong one? Or is somehow bent in such a way that the clutch will not fully engage? Honestly I don't know enough about Rover clutches (or any for that matter) to know if that is a possibility. If it is a possibility and it is happening I think that one symptom might be a bit more wear than expected on the throwout bearing.

LaneRover

scott
03-14-2007, 09:44 PM
n o b,

you're lucky that i'm so lazy. i put my tranny back in sunday and still haven't bolted down the seatbox or put in the floor boards so i was able to go out and snap this shot. there are 4 nuts, 3 are arrowed, the inspection port is outline in yellow.
http://www.roversnorth.com/forums/attachment.php?attachmentid=99&stc=1&d=1173926554

northoceanbeach
03-16-2007, 01:21 PM
Well, it's been raining here for the past couple days so I haven't gotten out to fixing things, I don't have a garage. I figure the last thing I want is my transmission getting rained IN. But it looks like today is going to be nice so I will open it and look inside and try the slave pressure test mentioned above.

Thanks alot for going to the trouble of taking the pictures, I really appreciate all the help.

BackInA88
03-16-2007, 03:29 PM
Well, it's been raining here for the past couple days so I haven't gotten out to fixing things, I don't have a garage. I figure the last thing I want is my transmission getting rained IN. But it looks like today is going to be nice so I will open it and look inside and try the slave pressure test mentioned above.

Thanks alot for going to the trouble of taking the pictures, I really appreciate all the help.


It's got to be rough dealing with rain when you have to put up with living in Hawaii!:p

LH Drive
03-18-2007, 04:50 AM
I also have a Series III and the only clutch adjustment I found was when I replaced the Clutch Master Cylinder.
In the attached picture you can see that the push rod is threaded on one side where it is attached to the clutch pedal. You will have to remove the dust cover on the clutch MC bracket. I had to remove the whole fender(wing) to get access to this on my 1972 left hand drive Series III.


Also make sure you don't have any air in the system. Bleed the clutch using some rubber tubbing atached to the slave cylinder slave bleed screw going into a jar filled 1/4 with some clutch fluid in it . Un-screw the slave bleed screw and pump the clutch pedal till you free the sytem of air. Keep an eye on the clutch master cylinder fluid level as it will empty. As soon as no more air bubbles appear in the jar, tighten the slave bleed screw with an open box wrench then remove the tube. This should give you full pedal hight.

scott
03-23-2007, 07:36 PM
best way to bleed a clutch or brake is a long tube that will reach from the bleed valve all the way back to the rez. fix the rez end so that it is submerged and stays submerged and pump away

LH Drive
03-25-2007, 12:07 PM
Were you sold the correct Clutch Release Bearing? Did you place them side by side, new next to old and see that they were the same. I've seen pictures of two different lengths, one tall and one short. Also did you tighten the PP all the way to mesh with the Fly Wheel? On a Diaphram PP this has to be done in a cross pattern gradually and evenly, if not you may damage the Clutch Disk plate. What kind of PP did you install, Diaphram or Coil spring cover ?

johnhlrbc
03-25-2007, 06:29 PM
I would agree with lh drive , I would be checking my release bearing , that its the right one , that its installed right , that its not binding or cock-eyed on its sleeve , Im not much into land rovers but I done a few clutches , it seems somthings not seated , or correctly assembled , [release bearing to the fork, ] the forks not in behind the bearing ?[ release bearing has a slot in it for the fork to fit into ?], keeping pressure on the presure plate fingers, You might be looking for another new clutch soon if you drive it much while its slipping