Clutch despair

Are you sure about a few thous? A new plate will have a vastly greater tolerance than that on the lining.

Check out those specialist clutch replacement outfits. It's all they do. I had years of lying on my back on cold concrete supporting gearboxes and clutch assemblies on my chest. Once swapped engines on a Morris Oxford single handed in a blizzard, using the lifting hook on a breakdown wagon as a lift. Probably why I'm knackered now. DaveK.

They also cater for the bottom of the market and use re-manufactured parts. A Stag is not the sort of car I'd trust to them.

In message , DaveK writes

And you try and tell the young people of today that ..... they won't believe you.

;)

High spots on a new plate are slightly different from warped plate, a warped plate is a bit like a spring wavy washer as a result you don't get a definite point when the clutch clears, or when it takes up, whereas high spots tend to give solid but localised contact. Also warped plates tend to show up when the clutch is past its midlife in terms of wear, with a diaphram clutch the geometry of the pressure plate mechanism means the the presure plate clamping ring moves about 40% less to clear the (worn) driven plate than it did when the clutch was new and the driven plate was thicker.

About 5 years ago my wife (then girlfriend) had a franchised clutch specialist in Reading completely knacker her Dolomite 1500. It took them 3 days to do the job. The initial delay was supposedly down to not having the correct tools, the clutch being fixed to the flywheel by allen headed bolts - they claimed never to have seen these before and didn't have the tools to remove them. When she eventually got the car back there was a nasty clutch judder (not there with the old worn clutch) and the overall release action wasn't smooth. I never took things apart again, but I felt they might have managed to bend the input shaft, or done something equally inept. Clutch changes don't get an awful lot simpler than on a Dolomite - if they can screw up on this, just think what they can do to something complex? Not impressed in a big way, I've done all of my own clutches since then, Cheers, Bill.

-- Rarebits4classics .......just what you've been looking for

PO Box 1232 Calne Wiltshire SN11 8WA United Kingdom

It shouldn't have been complex, but the worst clutch change I ever did was on my old Carlton last year. I'd been toying with the idea of scrapping the car due to the slipping clutch until I spotted a new kit on Ebay for a tenner. The kit was fine, brand new Borg & Beck, but getting the 'box off was a nightmare of seized bolts and strangely headed fasteners. Then to cap it all, I did one of the stupidest things I've ever done and lowered the back with the trolley jack while the front wheels were up on ramps, forgetting that I'd left it out of gear with the handbrake off while refitting the propshaft. I'm still not sure what stopped it rolling straight backwards and flattening me! Obvious lesson is that if you're too tired and fed up to work safely, leave it until the next day.

Also warped

Interesting - I have always suspected that the geometry change caused by wear of the plate would have this effect. I've never dismantled a diaphram pressure plate, but by drawing a simple diagram I have certainly convinced myself of this affect. You can certainly feel the increase in pedal pressure due to this change. I wonder if the self adjusting pressure plate clutches ( as fitted to the E46 ) will avoid the drag - they certainly do stop the large increase in pedal effort.

Thanks for the info.

Steve

Not many people drive a '73 as primary transportation so there should be plenty of time to plan ahead. If you buy a good manual most of the steps should be obvious. Four ramps should provide enough clearance.

Things like having to soak rusted fasteners ahead of time with solvent can slow you down but once the transmission is sitting on the trolley jack out of the way, things usually go quite smoothly.

I would spend a day underneath testing the trolley jack and checking all the fasteners and making sure I could undo them and retighten them with the tools I had. These things go quite smoothly if you plan ahead.

A good transmission jack will save you some trouble and can be rented by the day. When I replaced my clutch I just bought a cheap used trolley jack for 5 quid and bolted a plate that balanced the transmission better to the top. Worked fine.

On a '73 it might be advisable to buy a rear seal and spigot bearing in advance and figure out how you are going to jam the flywheel to remove the bolts as well.

Which seal do you mean ? Rear crank main bearing ?

If you are going to change the spigot bearing you need an extractor. This is a good point as they can be buggered - I tried to find a place that would hire me one - totally failed. In the end a very nice guy at work made me a rather Heath-Robinson ( but effective ) extractor..........

As to jamming flywheel - if you rotate it to a sensible position then the torque required to hold the flywheel still is negligable - I've never had any problem holding it by hand. Basically, the bolt you undo should be at 6 O'c*ck......

Steve

Find a tight fitting dowel of hard wood. Near fill the bearing with grease. Hammer in the dowel. Exit one bearing...

My preferred method involves a "Rawlbolt" expanding bolt and a length of tube.

Put Rawlbolt into pilot bearing. Put tube over the stud sticking out. Put nut on stud, tighten.

Rawlbolt expands into bearing, further winding on the stud pulls the bearing+bolt out of the end of the crankshaft.

That sounds like a good idea - I'll bear that in mind if my custom made extarctor ever gets lost/broken.

Hi Loz

Clutch plate stuck on spline of gearbox shaft?.

loz wrote: snip

Never done the Stag clutch but a 2000 clutch is a 3 to 4 manhour job, with the Stag it will be a bit more complicated -- v8 exhaust and the acccess isn't as good and the cooling system needs careful checking afterwards say 5 to 7 man hours + cost of material circa 140 pounds..

All things a pro mechanic deals with day in day out

Oh yes? Years ago I took a Series 1 XJ6 to an exhaust place to have the downpipes replaced - I *hate* doing exhausts unless a complete new system. After breaking three studs they said they'd have to take it to a dealer. There are no fast 'pro' ways to fix this sort of thing that I've found, so you'll just have to pay one way or another.

There's one obvious one - break it.

If you or I have a stuck manifold, we fiddle with it until we've got it apart, because otherwise we have to buy a new one.

If a garage mechanic has one, they force it until it either comes off, or breaks. Then the customer buys a new one and everyone curses the maker who made such an awkward part.

You can repair cars very quickly with an attitude of "You're going to get fixed right _now_", provided that the parts are still current and you don't mind buying them.

-- Die Gotterspammerung - Junkmail of the Gods