First time clutch replacement M54 2.2

[mrscalex]

I've got the exhaust, heat shields and propshaft off tonight. So tomorrow I'll be dropping the gearbox.

Obviously part of this process involves letting the engine and gearbox lean backwards as a jack is let-down under the gearbox. So I'm wondering what's sensible to disconnect in the engine bay that might get damaged as the engine goes back. So probably anything that is connected to the engine bay at one end and won't move as one.

The airbox has to come out anyway so I'll do that. But I'm looking at the aircon pipe and wondering what's going to happen to that unless I disconnect it from the compressor? Has anyone done a clutch on an air con car to advise?

I've found some notes from @NZ00Z3 on checking the condition of the DMF - https://zroadster.org/threads/dual-mass-flywheel.42215/#post-633363. Thanks. Very useful.

I really don't want to fork out £300 routinely for a DMF unless I have to. But I wondered what the wisdom is on doing this anyway while the clutch is out. The car has only done 72k.

 

[t-tony]

You can see how much “free movement” the DMF has once the gearbox is out. The outer part of the DMF which carries the clutch assy. will move back and forth under hand pressure before the engine starts to turn. It may be quite a lot. Personally I wouldn’t consider removing a clutch at 72,000 without replacing the whole thing, it has after all, done the same mileage. Most garages won’t entertain not changing it all to cover themselves. I have seen first hand the issues which can arise. The only other option I would consider is fitting a SMF instead.

Tony.

 

[NZ00Z3]

My research says to replace the DMF at the same time as the clutch.

When I did the clutch on my 2.0L Z3 with M52TUB20 engine, I a half hour climbing under the car, lowered it a bit, jumping back out and looked at all connections etc to what would bind, reach limits first. Turns out it is the heater valve on the fire wall behind the inlet manifold. The aircon pipes where fine and where not disconnected.

Tips for the job include:

• Support the car well and high enough so you can pull the transmission out the side from under the car. It's quiet high. I used four 3 ton axel stands designed for 4WD's to get a high stable platform.
• A 2 ton hydraulic floor jack with a simple plywood and wooden block transmission cradle works well for the heavy lifting of the transmission off/on the engine.
• Once the transmission has been lowered until the inlet manifold just about touches the heater valve, cut come 4x2 wood to block the back of the oil pan/sump from dropping lower and the front of the oil pan/sump from jumping forward when the transmission is removed. Don't know what the balance point is, but I had other work to do on the engine when the transmission was out, so did not risk it coming forward and into the radiator.
• Two 12" extensions and a universal are needed to get to the two top transmission bolts.
• There is a 10mm bolt that holds the spacer plate onto the transmission on the drivers/right hand side. It goes front to back. All other bolts go from back to front. This means the 10mm bolt is often overlooked. The transmission will not come out with the bolt still in.
• The start motor has a locating/earth pin that likes to hold on tight. You need to clearly separate the starter motor from its mount. Otherwise you'll get to pull the transmission back about 1" and then no more as the start motor is still attached and you are pulling on the starter motor cables.
• The transmission to engine bolts have a special coating on them to stop galling. The general wisdom, is to buy new bolts as the original one are good for 1 1/2 uses. Some people apply anticize on the original bolts and trust their luck. Having a galled bolt, 1/2 way in, is a world of pain. Tight access to cut the bolt head off. Remove the transmission and drill out/insert a time sert, then refit the transmission and give the now already twice used bolts a go. Often it results in an engine removal job to fix the galled bolt.
• I made up two alignment pins to help refitting. Normal bolts for the 2 large bottom holes. Heads cut off and a screwdriver slot cut into the end with a hacksaw. They stick out just a bit more than the length of the piolet bearing shaft on the end of the input shaft. Fitted these loose and used them to align and guide the transmission on the way in. It was a breeze of a job. No twisting and fighting the transmission to get the input shaft into the piolet bearing. A big screwdriver easily removed the pins.

It's a fun job, enjoy.

 

[mrscalex]

Thanks both. Some great advice there.

 

[t-tony]

In the real world of the motor trade I can honestly say I have never experienced removing bell housing bolts which wouldn’t go back after replacing a clutch. I have doubts that this would happen at a BMW dealership workshop. Definitely a good idea using dowels from cut down bolts if you’re doing it on your back though.

Tony.

 

[mrscalex]

The last time I did a clutch was when I was 19 on a Mk 1 Escort. I've never had such a dire experience. I just couldn't get the input shaft lined-up on reassembly. I managed it in the end but the physical discomfort and pain laying on my back and bench pressing it was horrible. It nearly had me in tears. On the plus side I guess not many 19 year olds, especially with little more than a socket set would ever have tried!

I wont be bench pressing this one. It will be going up and down on my motorbike scissor stand.

 

[t-tony]

That is another problem with a DMF. With a “normal” flywheel and clutch the only lining up tool you need is your fingers. You can feel directlly how close the edge of the driven disc is to the edge of the flywheel with your finger tip. It’s amazing how accurate you can be doing this. In a DMF system you cannot do this and need a dummy spigot to alight he parts before tightening the bolts which hold the clutch cover to the flywheel.

Tony.

 

[mrscalex]

That is another problem with a DMF. With a “normal” flywheel and clutch the only lining up tool you need is your fingers. You can feel directlly how close the edge of the driven disc is to the edge of the flywheel with your finger tip. It’s amazing how accurate you can be doing this. In a DMF system you cannot do this and need a dummy spigot to alight he parts before tightening the bolts which hold the clutch cover to the flywheel.

Tony.

I used an alignment tool even on the Escort. In fact I've still got it - I wonder if it will fit.

One more thing you might be able to enlighten me on Tony. This is a self-adjusting clutch I believe. Does it bolt straight up. Is there something to release on installation. Does it need a special tool to set it.

 

[NZ00Z3]

A new Self adjusting clutch comes with a spider holding the clutch fingers at a slight pressure. You fit the clutch. The alignment tool goes through the spider. Once the pressure plate is fully tightened, you remove the spider. If you have to remove the clutch, put the spider back on before removing the pressure plate.

 

[mrscalex]

A new Self adjusting clutch comes with a spider holding the clutch fingers at a slight pressure. You fit the clutch. The alignment tool goes through the spider. Once the pressure plate is fully tightened, you remove the spider. If you have to remove the clutch, put the spider back on before removing the pressure plate.

Ah it's that simple is it. Thank you.

 

[Pingu]

I use a wooden cradle to hold the gearbox. The gearbox sits in the cradle and the cradle goes on the trolley jack. It allows for the enevitable rocking that you will need to do.

I also remove the fan, as it can foul the radiator or the shrouding.

I use a tool that locks the flywheel. The alternative usual suspects (pry-bar, screwdriver) all need three hands.

 

[motco]

In the real world of the motor trade I can honestly say I have never experienced removing bell housing bolts which wouldn’t go back after replacing a clutch. I have doubts that this would happen at a BMW dealership workshop. Definitely a good idea using dowels from cut down bolts if you’re doing it on your back though.

Tony.

Blimey! My 1955 Standard Ten had dowels already fitted as part of the design! How do I know? I spent half an hour trying to start a nut on the top one by feel as it was out of sight! That was when I was young and agile... now I'm neither sadly.

 

[Lee]

Done a fair few of these now,

We always remove the viscous fan because it clashes with the rad if you let the engine centre itself once the gearbox is off plus when tilting to access the linkage.

You'll be able to access most of the bellhousing bolts from below don't forget the the small 10mm hex head exhaust side holding the shield in place between the gearbox and engine.

From above reach around the inlet manifold you'll need to remove the two starter motor bolts and give it a good up/down shake to release it off the dowel. You'll also need to reach across to the two big bolts on the back of the engine around about 12-2 position. We reach all these top bolts using a selection of extensions from the end of the gearbox all the way through.

I also only ever remove a box with 2 men minimum.

 

[mrscalex]

Some more great advice. Thank you. All these little things make the difference between it going well or not.

Interesting that you always do it as a 2 man job @Lee. The little fella has gone off to university now so it's just me currently.

 

[Lee]

You might struggle because I very much doubt you'll get enough room to swing a ratchet on the bellhousing bolts at the top, and doing them with extensions your doing it blind we normally have a person at each end, one doing the undoing and one guiding the socket on. We also use a breaker bar to undo them as they've not moved in 20+ years. We had a run of 7 gearbox jobs at the start of this year I was dreaming gearboxes

 

[mrscalex]

You might struggle because I very much doubt you'll get enough room to swing a ratchet on the bellhousing bolts at the top, and doing them with extensions your doing it blind we normally have a person at each end, one doing the undoing and one guiding the socket on. We also use a breaker bar to undo them as they've not moved in 20+ years. We had a run of 7 gearbox jobs at the start of this year I was dreaming gearboxes

I'm glad you said that's where the help is needed. Thought you might have meant it was silly trying to get the gearbox down with 1 person. I've managed the diff on my own with my trusty bike stand jack so hopefully okay here. My daughter's back from uni now so she'll have to start getting her hands dirty. It's either her, my 88 year old Mum or the 68 year old lady next door who said she would help...

 

[mrscalex]

In terms of supporting the engine to stop it flopping forward with the gearbox off... I'm planning to let the engine/box drop at the back to where it needs to be and then getting a bottle jack with piece of wood under the front of the engine. Then when the gearbox is off and it wants to flop forward it can't go anywhere. Plus it's in the right position to then put the gearbox back later.

Is that a plan or does it not work like that?

 

[t-tony]

Removing the fan is a better safe than sorry if the bottle Jack slips Rob.

Tony.

ps. If you’re using lots of extensions to reach the bolts you’re better using 1/2” rather than 3/8“ as you don’t get as much twisting before you loosen the fixing and it won’t loosen with such a bang either.

 

[Lee]

In terms of supporting the engine to stop it flopping forward with the gearbox off... I'm planning to let the engine/box drop at the back to where it needs to be and then getting a bottle jack with piece of wood under the front of the engine. Then when the gearbox is off and it wants to flop forward it can't go anywhere. Plus it's in the right position to then put the gearbox back later.

Is that a plan or does it not work like that?

That's pretty much what we do, we use a bottle jack sat on some bricks this also helps giving the engine a tilt when re aligning the gearbox later.

Just remembered theres a heater valve on the bulkhead right behind the inlet manifold, unhook it off the bracket or it will get squashed when you tilt the engine. You'll need most tilt when unhooking the gear linkages as this is done blind.

 

[mrscalex]

More good tips there. Thanks both. I did already remove the heater valve guessing that could only help. I'll remove the fan for some insurance.

I've taken the air box off as well so the intake hose can move freely. Though I'm still a bit surprised Murray had no issues with his air con hose which is the only other non-flexible attachment to the engine bay I can think of. Or perhaps there's a rubber section under the heat shield that soaks up the movement.