Marea 20v Gearbox removal/refitting


You will Need
A decent ratchet
A breaker bar of some sort
Ratchet extension bars
The following sockets, 10mm 13mm 15mm 17mm 18mm 19mm
The following spanners, 10mm 13mm 15mm 17mm 18mm
Allen keys
A hammer
Long flat ended screw driver or similar to lever with
Tin of WD40
Long tie wraps, to tie items up with
A good jack
Minimum of 2 axle stands
A hoist, or some method of supporting/moving the weight of the box
The facilities to make lots of cups of Tea/Coffee and a few bacon sandwiches.

I have found that there are easy ways to keep the relevant bolts together. If I remove the starter motor, I will tape the 3 bolts together and label as starter motor. On the mounts I will carefully place mount and bolts together. Often once an item is removed I will loosely screw the bolts back in. You will not be left with a pile of nuts and bolts this way.

Jack car up, Apply handbrake, jack the car up on both sides and use axle stands. Remove both front wheels.

[Unbolt passenger side wishbone, 4x 15mm bolts, unbolt antiroll bar where it passes through the wishbone and unbolt track rod end.

Remove brake calliper, 2x 19mm, gently ease the brake pipe out the clip on the damper. Tie up the calliper out the way.

Unbolt hub, undo 2x strut to hub bolts. You will have to undo the abs sensor to pull the lower bolt out fully from the strut. I undid the Allen key and tapped it round to allow the bolt clearance.

[BREAK=In the engine bay]

The idea with these next few items is to give you room to work, the battery tray and slave cylinder are necessity but the resonator box and induction piping removal is to allow you to have space and see what you are doing.

Remove battery and tray, remove battery first. It should have a bolt and plate trapping it, slacken or remove this. 2x terminals are 10mm loosen these. Remove negative 1st and be sure that you have any radio codes etc. pre written down then remove the battery. The tray is 4x 13mm bolts. 1 is hidden underneath towards the front of tray. There are 2x 10mm bolts holding on a wiring loom bracket at the back of the battery tray, remove the 2x nuts. Lift tray out.

Remove slave cylinder, from top of gearbox, Remove 2x 13mm bolts that hold cylinder, unclip pipe from bracket to allow you to lift up the slave cylinder and tie up out the way.

Remove air intake piping, removefrom between the throttle body and air-box. Clips are not reusable and will need replacing with jubilee clips.

Remove the air resonator box and cover, this is located tight against the right hand side of the engine. Remove 2x 10mm bolts and lift black plastic cover off. This exposes resonator box. This is held by 2x 10mm bolts. One in the side and one at the front. Remove.

[BREAK=Under the car]

Undo exhaust, 2x 13mm bolts holding exhaust down pipe to the manifold. One of these has a securing bracket on. Further along the exhaust there are 2x13mm bolts holding exhaust to a securing bracket. By removing the exhaust it will give you more room to work. It is not a necessity but makes things easier.

Remove the 4x 17mm nuts from the sump support plate which sits under the exhaust across the sump. This will allow the exhaust to drop down. I put this back on after the exhaust was clear as you will need an axle stand on the sump and this strengthens the sump.

Place a jack or axle stand under engine, I placed mine with a chock of wood on the edge of the sump support plate. Next to the main sump section. Be careful not to damage the sump as they are fragile.

Remove rear engine steady (mount) remove single bolt where it passes up into the chassis. And 2x 13mm bolts. going into sub frame.

Drop sub frame, there are around 8 bolts 2x 19 where the sub frame bolts at the furthest ends in the wheel arch. Then there are 2x18 as it bolts under the bulkhead and the rest are 15mm two of these 15mm bolts are long and secure the steering rack. The sub frame might need a tap to drop down.

Remove starter motor, there are 3x 13mm bolts. The starter motor is placed on the back of the gear box in the most awkward place you could imagine. It is difficult to see yet alone remove. To remove the lowest of the bolts I went underneath the car.
It is possible I think to remove the other 2x 13mm bolts from underneath however would be tricky. One bolt even more so than the other. It would be getting them back in that would cause the headache.

For this reason I removed the throttle body from the car. I undid 4x Allen key bolts, this separates the throttle body from the induction manifold, I then undid a hose, the throttle cable an air hose and a couple of electrical pin connectors. Only enough to pull the throttle body out the way. With this out the way you can now get your hand through the newly created gap and access much more easily the 2x 13mm Starter bolts. With these removed pull the starter motor back and out the way, tie it up if need be.

Remove gear linkage, there are 3 arms at the back of the gear box next to the bulk head.
You can 1: pop the ball and cup joints apart. Or if awkward 2: you can undo the front 2 balls with a 13mm spanner. Once loosened you will need a second open ended spanner to stop the whole lot spinning. Should make sense when you look for yourself Tie the linkage out of the way to prevent damage to them.

[BREAK=Removing the box]
Undo Gearbox bolts, the main bolts are 18mm there are, I think 3x bolts on the top going round the box in an anticlockwise direction. Next is a 15mm bolt that is level with the exhaust manifold join, it is screwed in from the other direction. These are easily seen. There is another 15mm at the very bottom of the box ( my memory is struggling here) Next still working in an anti clockwise direction is an 18mm that passes through the mount assembly.

At this stage I always replace a couple of 18mm bolts into the gearbox only just starting a few threads. ( as a support )

Engine Hoist, I placed an engine hoist with a rope around the box and tensioned the rope so that it was just under tension. Make sure your rope is not going to damage anything when it pulls tight.

Rear mount bracket, this is bolted to both the gearbox and engine in such a way that it has to be removed. From memory there is another 18mm bolt which holds it to the engine as well as two 15mm bolts one of which I think goes into the gearbox. Have a feel around, you will know when all the bolts are all out as you will be able to remove it.

Remove electrical connections, there is a pin socket at the rear of the box. Also there is an earth wire at the front right hand corner, 13mm bolt.

Remove front gearbox mount, I removed the whole thing for clearance. Is self evident and you can decide how best to separate it. There are 4x bolts to the gearbox and 1x long bolt going straight up that joins both halves of mount to each other.

Check round the gearbox, make sure there are no brackets holding any wires or cables, that all items are away. Make sure all but the bolts you have put in to secure the box are out.

Remove box, Making sure the hoist is still under tension, remove the 2x bolts you put in to secure the box. Pull or wiggle the box apart. Often It is an idea to gently tap a wedge between the box and engine where you are wishing to separate it. Try and open the box up evenly. If you do this then do it around the 18mm bolt holes. Be careful not to damage the gearbox alloy or to bend the tin black cover plates.

As the box separates be careful to keep the tension on the hoist as the box needs to separate level. Take care not to damage the drivers drive shaft.

To reassemble It is a reverse process, I always replace any drive shaft seals where the shaft has been disturbed as they can then leak.


New member
Jul 25, 2009
What a horrible job!! my cars been apart for weeks now! luckily the gearbox is off now and i've got a new (bargain) clutch to go in, just need to remember where everything goes!!
The bolts through the subframe into the steering rack - do they have nuts on the other side??
Sep 28, 2007
West Midlands
Hiya mate,

Just to let you know these clips on the pipe work are re-useable! You should have a special tool, but you can do it with a pair of wire cutters. I leaves a cleaner finish and saves you money.

Not being silly, just thought I'd let you know
Keep up the good work (y)