when trying to reverse it was trying to stall as if it were trying to go forward as well then it wouldent go into neutural just kept going forwards even kept going forwards with the clush/drive peddle pushed down then wont go forwards seemes as if it is slipping but would go backwards then worked fine now i cant change gear with the engine runing and depresing the button on the gearstick makes no difference

i know that the altinator is on the way out will this have any effect on my problems

i am open to sugestions

Sounds Like.........If trying to drive forwards at all times the engine is running, the forward clutch packs are binding, they may have got hot and buckled.  This should have no relation at all to the alternator.

 If it is a Teleporter 2 as you say, it will have a cable controling forward / reverse, and an electronic dump solenoid on the end of the same shaft going into the box. 

Conclusion.... Remove shuttle box and replace damaged parts.

I have seen these people, they should be able to help, www.sandersonparts.co.uk

Sparepart is correct in his diagnosis , however if it is the old Borg "Velvet shuttle " box they usually have a tendency to keep going in reverse and have the forward direction fail if it is down to the clutch plates as the forward plates are a lot smaller.

Before you take out the box , check these out. If I remember correctly on some machines there are a couple of Ball joints on the Forward and Reverse control if they wear or the cable stretches then the lever on the box will not move into reverse.

Also on the gearbox itself check that the spool (connected to the lever) is moving correctly, and if necessary check the seals are not allowing it to leak internally. These valves were notorius on some machines for eroding the casings and giving this sort of problem.

If you need to repair the transmission try ATP Industrial at Hednesford , they manufacture there own repair parts and modifications and very familiar with this unit.

If you want to have a go yourself and need a service manual let me know. They are dead easy to work on so long as the casing etc isnt worn or damaged.