Hi Trevor,
I have done this and it would be the easiest boat in the world to work on in this area.
Ours is SM 299 with the ZF (or Hurth as they used to be) and a Volvo TMD22.
There is a Vetus connector between the gearbox and the C drive.
Undo the four bolts holding this together. To move the motor forward prepare by removing the cables to the gearshift.. You may have to remove the flexible exhaust connection from the motor, in ours I didn't, there was enough movement available.
Remove the water pipes to the oil cooler (both in and out) first turning off the sea cock..
Check all cables and fuel lines to the motor, we did not have to remove any, you may.
As you shift the motor watch carefully that nothing is pulling up short or snagging.
You only need to move the motor around 150mm (six inches).
 Now undo the 4 large  bolts securing the motor to the angle iron engine beds. Take the bolts out. Now the engine is ready to be slid forward.
 I do this by using a piece of 75 x 50mm (2" x 3") timber as a lever. (this is what make the Amel so easy, most boats you have to take the engine off the engine mounts and physically lift it to move it.)
Slide it a little at a time ensuring the the bolts through the vetus slide free. If you cannot remove the nuts on these before you move the motor (no room for the nut to come off) just move the motor a little then take the nuts off. 
Once the motor is moved you have 6 ( I think) nuts to remove on the back of the motor that hold a dish shaped housing on to the motor to which the gear box is fixed. Undo these and you can lift the gear box off along with the dish shaped housing. 

There is a spline into what looks like a car clutch plate that is bolted to the flywheel of the engine into which the gearbox shaft enters. There are a series of springs in this for shock absorbsion. If they have never been replaced it may be a good idea to do this while the gear box is off. If you don't do this there is no need to take this plate off the fly wheel. Likewise there are 4 rubber bushes in the Vetus connector with a dual role, correcting (very) minor alignment issues and providing shock absorbsion.
Hope this helps. I reiterate, it is the easiest boat you will ever find if you have to move the motor.
Regards
Danny
SM 299 Ocean pearl
Currently home port Mangonui New Zealand  
 
Dear All,does anyone know the correct sequence and procedure of where and how to split the drive train between my ZF 25 and the C drive to allow me to remove and replace the gearbox.The boat is in the water and it appears that either the engine has to move forwards or the top part of the Cdrive needs to de dismantled? Neither option is attractive.Any advice would be very much appreciated.Thank you very much.Trevor LustySeafever of CuanSupermaramu no 425Mexico

From: seafeverofcuan <seafeverofcuan@...>
To: amelyachtowners@...
Sent: Wednesday, 20 February 2013 1:44 PM
Subject: [Amel] Transmission removal


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