Canadian Disco 2 Build

[R_Lefebvre]

Well, I put it all back together, and took it for a test drive. There was a rattle, which turned out to just the exhaust rattling on my gas tank skid. I guess the exhaust didn't bolt up exactly as it came out. Easy to sort that.

Other than that, things seemed to be going ok. Other than the fact I don't have a shift knob on the stick yet. But then when I left my neighborhood and went onto the open road, I noticed that the clutch is slipping quite badly in 3rd, 4th and 5th gears. Just steady 1/2 throttle application, and it just lights up. I don't know if it just needs to be broken in...? I've never had something like that on any of the brand new cars I've bought with manual trans.

What could be causing it? It's a brand new flywheel, with a brand new AP clutch from Ashcroft.

Is there any chance that a poorly bled clutch hydraulic circuit would do it? Somehow not let the pressure out? I had trouble with bleeding the clutch. Rather, I had trouble with the guy helping me.

Oils on the new flywheel and pressure plate that just need to burn off? Again, I've never had anything like this on any of about 10 manual trans cars I've owned. It slips really quite badly.

Oh, and I never smelled the clutch at all. I didn't roast it, I did that in my Mustang once and you sure smelled it. This, nothing.

 

[AxeAngel]

Keep it in first, stop often. Start back up from a full stop in first gently lettingthe clutch out. You have to do it alot or like I said just drive around in rush hour traffic.

I've never heard of a clutch slipping that bad even after installing a new clutch and bleeding. When you installed the clutch did you center it correctly? How does the pedal feel?

-Sam

 

[R_Lefebvre]

Yeah, for sure it's centered properly with the tool I made. If not, I would never have gotten the box on I think?

The pedal feels... well it's a hydraulic clutch.... it feels like nothing. It has some resistance, but very little feel, which is why I wonder if it's not bled right. Still, not being bled right should lead to the opposite problem: it won't disengage, leading to trouble changing gears. That's not the case, though 3rd and 4th are still a bit baulky.

I'm wondering if it's some kind of stupid "Oh, you didn't DO that?!" Never put a new clutch in before. Are you supposed to clean off the pressure plate? Something stupid. Or a parts mis-match.

One way I can check is to unbolt the Slave, and try driving like that, see if it still slips. Trouble how to get into 3rd.

 

[LandyAndy]

When ever I fitted a new clutch I usually cleaned the flywheel & pressure plate with brake cleaner but it've also had cars that had leaking crank seals that puked oil into the bell hsg with little issue.

You could try packing some washers between the slave cyl. & mounting face to move the shaft stroke back a bit. Would give you an idea if it's internal and some mis-matched parts problem.... only way I can see it slipping is if the gap between the cover plate & flywheel is too large, or the release brg can't move back far enough.

 

[AxeAngel]

Rob,

My S has a hydraulic clutch, definitely feels lighter than a manual clutch, but its definitely there. If you didnt bleed it right or were lacking brake fluid, you wouldnt be able to push in the clutch.

Might sound like a silly question, but it could answer a lot of my related questions. How is reverse?

-Sam

 

[R_Lefebvre]

Reverse is fine.

Dang it, Dave Ashcroft is on vacation.

 

[Root Moose]

Start with the easy stuff... re-bleed the clutch.

 

[R_Lefebvre]

Yeah, after driving it more... it just doesn't feel consistent. It's kinda squishy and the last inch is much firmer than the top, and it shifts better if I consciously push it all the way down. I had a neighbor helping me who is an airforce machinist who... one of those old guys who knows it all... but I'm not too sure. He insisted on pumping the clutch 10-20 times really fast between bleed screw openings. I could see it was just making a milk shake out of the oil, but it's hard to ask a guy for help doing something and then telling him to stop giving advice. Eventually I just called it good enough. I just needed somebody to push the clutch. I'll get my wife to help tonight.

But, I'm pretty sure the clutch slipping is caused by not cleaning the flywheel and clutch cover. Seems it's one of those things you're just supposed to know. I've never replaced a clutch before so... I'm sure I would have seen it if I'd been researching just doing a clutch job. But this was so involved with so many other things to think about, I missed a stupid little thing. At that point I was concentrating on finding the right length bolts, and making the clutch centering tool.

I drove the truck to work today. Went well, other than the slipping clutch. But I did get it up to 100km/h. (Yes, it is an accomplishment, that's how bad it slips). It revs so high, I definitely am interested in trying the 1.0 transfer case ratio from the standard 1.2. It turns about 2200rpm at 100 km/h which is crazy high for a V8, IMO. The 4.6 has bags of torque down low, it just doesn't need to turn that fast on the highway. If I swapped to 1.0 high range ratio, it'd be turning about 1800, more reasonable.

At this point, I'm going to bleed the clutch, and drive it around, take it easy so as not to burn the flywheel, see if the oil burns off. If I have to open it back up, I'm definitely going to put a new clutch disk in. I'm not going to just try cleaning it and hope that the disk isn't ruined by the oil. For $1-200, and all that effort, I'll just put a new disk in.

And by oil... I did check the surface. Both were "dry". There was no obvious oil film if you wiped your finger, at all. I don't think you'd pick anything up with a kleenex if you'd wiped it with that. If there's oil on it, it's just the slightest film. And the clutch shipped in the box with the disk sitting on the pressure plate. I would have thought if the oil would ruin the disk, they'd seperate the two.

Overall, I'm... meh... It blows if I missed something stupid like this. But on the other hand, if this is the worst of my troubles... I'll take it.

 

[AxeAngel]

Rob,

Is there something coming out of the slave cylinder like a rod, that is adjustable? Or alternatively the rod going into the MC. That is a point of adjustment on some hydraulic clutches...

Are your pedals adjustable?

My thinking is that your clutch isnt disengaging all the way, and its getting progressively hotter as you drive which will manifest in more slipping as it heats up. Are you noticing it gets worse or stays the same the more you drive?

-Sam

 

[R_Lefebvre]

Yes, there's a rod in the slave, but it's not adjustable. Still, it could be a parts mismatch. Something to check. I ordered the rod, and the clutch fork. But then both came assembled in the bellhousing from Ashcroft, so I used what they had given rather than the ones I bought, assuming that they got it right. The rest of the box has the right parts for the V8 Disco, so I'm assuming they knew what they were building.

The pedals are not adjustable any way I can see, unless the MC pushrod threads into the cylinder? I'll double check, but I'm quite sure the clutch pedal isn't pushing up against the stop.

I'm using a D1 clutch pedal in a D2 pedal box, so there is that oddity. But as I said, I'm quite sure the MC is stroking all the way out, but will check.

 

[Root Moose]

Sounds like you need more hydraulic fluid in the catch can when bleeding. The pumping and pumping that your neighbour did is correct procedure. The clutch bleeds in both directions, up and down stroke of the pedal. Make sure you have a couple of inches of fluid in the can and that the hose does not break the surface.

I just went through this with the S last week. All the previous vehicles I had dealt with had cable clutches so I didn't know how to bleed a clutch. Works like a charm now (pedal fell to the floor and stayed there before).

 

[R_Lefebvre]

I did the open and close of the valve, the same way I always do for brakes. I've tried the hose in the fluid cup before on brakes, and never got good results. Sometimes it sucks in air from around the bleed screw threads. I'll try it again

If I have to, OEM clutch plate for 98 quid.

http://www.rimmerbros.co.uk/Item--i-8510309

 

[R_Lefebvre]

No good way to see up into the bellhousing. Maybe if I removed the slave cylinder, I could use an inspection camera (which I don't have).

2)I actually thought of that. There's no easy way... The drain hole I drilled in the bottom lines up with the flywheel itself. I can *just* see the edge of the pressure plate. I could take the transmission tunnel cover plate off, access the vent line I drilled in the top of the bellhousing, and spray in there. That would get the PP side of the assembly. But it would be indiscrimate. I'd worry about washing all the grease out of the throwout bearing, clutch fork fulcrum, etc?

3) AFAIK, there is only one flywheel available for the engine. There was no obvious obvious step on the flywheel at all:

Unless it's dished very slightly and I didn't notice. I could feel the PP springs loading up as I tightened the cover bolts, so I know if got loaded pretty good.

The disk and PP came as a kit, made by AP, purchased from the most knowledgable LR transmission vendor. He's on vacation until next Wednesday.

I think of all the possibilities, that is the least likely?

 

[Root Moose]

I did the open and close of the valve, the same way I always do for brakes. I've tried the hose in the fluid cup before on brakes, and never got good results. Sometimes it sucks in air from around the bleed screw threads. I'll try it again

Yeah, the open and close method doesn't work - that is what I did initially.

Lots of fluid in the catch can and go to town on the pedal.

http://www.mco.org/phpbb/viewtopic.php?f=3&t=11897

 

[R_Lefebvre]

Alright, I'll give it a shot.

I have a power bleeder too, but the cap won't attach to the reservoir in this truck. Regardless, I've always had the best result bleeding brakes with the push-open-close-release-push-open-close-release method. What I do now for brakes, I do the bulk of it with the pressure bleeder, then give each caliper a couple shots of the old fashioned method.

Regardless, I'll try the bottle trick, nothing to lose, and the clutch is different than the brakes.