The Classic Machinery Network

So I had a problem with a Thwaites twin cylinder Petter PH2 engined dumper, not sure of model but is 4wd The clutch wouldn't engage so if I managed to crunch it into gear whatever I did with clutch it would not release fully meaning dumper kept driving, Altered clutch rod etc, did all standard things but felt as though not traveling far enough, (infact it felt as it was travelling too far as could feel release bearing hitting clutch springs!), anyhow so I decided to look at clutch and replace whatever I needed! So I`ve removed prop shaft, disconnected clutch lever undone all bolts around housing, checked and rechecked cannot see anything holding it in place but it just will not come off. infact it hardly moves at all, Tried reconnecting clutch and press on the peddle and it moves box about 1/4inch away from engine on one side but then springs back!! Any one any ideas??? as currently losing will to live!! It cant be that hard?? what am i missing HELP Please!!¬

Sounds like you've got two problems conspiring to make your life interesting.
- the friction disc seems to seized on the splines of the input shaft as well as being frozen onto the flywheel

Is there any access through the bell housing to see the pressure plate?
If so, go in through there and unbolt the pressure plate and take it all with the box.

I think that gecko has nailed the issue pretty well.
In your post you mentioned that you "altered the clutch rod", what did you alter?
Keep us informed with any and all progress or issues.
I had a clutch plate freeze on an old vintage car once and was able to unstick by having someone tow the vehicle while holding the clutch pedal down and hitting the brakes severely.

We used to have an early Thwaites 4000 with Petter 2cyl. When stood for a few months the clutch would seize. We either towed it out of shed and sometime that would free it. Alternatively, with enough room, start in gear and drive with clutch depressed and hit brakes a few times.i used to leave it with clutch wedged down.