Colin,
I have tried to do this with the large syringe used for sucking oil out of car gearboxes but it is very hard to pump liquid grease in this way, I can only suggest a pump type grease gun either manual or electric plus a long piece of rubber hose to direct the grease into the ends of the gearbox.
Hi Mike I know Im probably being thick here but where do you put the grease in though as I havent been able to find a filler unless it goes in the clutch adjuster hole
It does go in the clutch adjuster cap. I use semi fluid grease that I buy off a guy at Kempton. It's nicknamed "Strawberry Jam" This stuff is runny enough to be pumped in with an oil can. But before that I've used a thicker variant which I warmed up the tin before I used it to thin the stuff a bit, then just kept poring it in through the filler hole and rodding it down with a piece of thin bar. It took me quite a while that time.
The "Jam" is so easy and I also use it in my Royal Enfield's. Unfortunately I don't have a contact number for the guy who sells it. Ron
Morris oils do a semi fluid grease. It's a 3kg tin and will probably last you a lifetime.
If your suck obtaining it, I can get it in for you as PES is a agent for Morris oils including industrial.
We use it in our gear shaping machines.
We have 3 WD G3l's in the family and all have their gearboxes lubed by Landrover one shot swivel housing grease. (I run a Landrover garage,so it is "free" to me...) The stuff I buy from them comes in sachets and is easy to squeeze into the filler cap. Google finds it easily, or you should be able to get it from any Landrover garage. It works very well.