ICQ>

I have a 73 MGB-GT, which also has the Laycock OD unit in it. I was going through the same thing on a trip on weekend. My OD was having trouble engaging, or would suddenly disengage. Well, I was going down I-70 in the middle of the night, and !!BANG!! My Universal Joint broke. There I was on the side of the road at 1am. The hick I got towed to said I needed I clutch, and I think an hour or two after he put the car in the air, the prop shaft must have hit the floor, instantly signalling a misdiagnosis.

Things to check- transmission oil level, (which also supplies the OD unit)

OD solenoid- this is behind a plate at the bottom of the OD unit. There are about six small bolts that hold down the cover plate- be careful- I broke one and had to drill it out. Anyway, make sure the fluid passageways are clean and the solenoid is in good working order. Also check the grade/quality of fluid in the tranny- it should be whatever is in the engine. Go buy the combination filter/gasket BEFORE you take the plate off, it doesn't come off without "help."

BTW- the documentation for the MG says the clutch need not be engaged to move the OD in/out. However, the presence of the turbo may provide more power than the OD can handle, yet the MGB-V8 came with the same OD unit. As long as you don't go deep into the throttle in 3rd and engage the OD, you should be OK. As for the smoothness of a downshift, I've noticed that there is a difference between 3rd and 4th gear when you disengage OD. I generally go directly from 4th OD to 3rd OD, (using the clutch:-), then to just plain 3rd. The only time it gets rough is when I need passing torque (as MGB's do) and I have to go from 4th OD to 4th at 50-60 mph.