|» Index Page
||Introduction, About the BMW M70 V12
|» This Page
|» Page 2
||Fault finding, condition checking
|» Page 3
||Stripping and cleaning
|» Page 4
||Re-assmebly, Timing chain & heads
|» Page 5
||Here's a picture of the engine before major work
began. The silver boxes in the bottom left hand corner of the
picture are the two Motronic fuel computers and the EML unit.
The missing box is the ABS/Traction control computer. You can
see from the picture that the engine bay is really quite clean.
At this point the bonnet is still installed on the car, and
its one of the first things you ought to remove. Its also worthwhile
raising the car a few inches to make it easier to work on. I
had the benefit of a two poster ramp so I could place the car
at any height I desired. Before I did anything else, I made
a point of moving around the car and disconnected every single
computer and module on the car, and made sure that the engine
would still turn over without fault lights. My greatest concern
was that the transmission control computer or vehicle alarm
would cause problems, but to my great relief, the engine runs
fine without any of them. At one point there were only a handful
of relays and three fuses fitted to the car.
||Next photo shows the engine shortly before removal.
It helps greatly to remove the exhaust manifolds before attempting
to get to the bell housing bolts. The flywheel is held to the
torque converter with three bolts, a small access panel on the
front of the engine allows access to these. You can see from
the photos that all the cables and engine loom are draped across
the top of the engine. This allows you to see if there are any
other wires that should go to the engine that are still connected
and could potentially snag the engine on its way out. The air
conditioning needs to be evacuated now unless you want to remove
the compressor and tie it out of the way. My air con system
was empty due to a holed air con radiator, so I could just pull
the lines and clutch wires from it without any problems. When
removing a section of loom in this way, the best thing to do
is not cut a single wire unless you are absolutely sure you
don't need it. For remote items such as the throttle potentiometer
etc, make sure you cut the wires past the components connector,
you can reuse these and it makes future replacement a whole
|Here the engine is clear of the BMW. Its difficult
to see, but this engine is pretty compact considering its a
V12, its seems to be only a bit longer than the Rover v8, and
its certainly more modern looking. The sump is an odd shape
to accommodate the steering gear on the BMW, but will not be
a problem in my application. The viscous fan at the front of
the engine can be discarded as it will not be used. Examination
of the engine at this point revealed a few interesting points.
First was that the spark plugs at the rear of the engine on
the right hand side (passenger side), had NEVER been changed.
I found this amusing as the car had full BMW service history.
The reason that they had never been touched is the brake servo
is so close, limiting access to tools. Secondly, I discovered
a broken HT lead and a bodged repair to another of the HT leads.
It surprising the car ran as well as it did considering these
faults with the ignition present.