[Jon Bradshaw]

I have my reproduction Vickers tank running on a reversed T16 hull and when it was out today the seal where the diff meets the drive shaft leaked fluid. It was only about 1 cup of oil but it made me put it back on it's trailer and head home. Once home I opened up the engine bay (remember Tank hull, armoured engine covers, lots of lifting)looking for where the oil had come from. It was puddled under the seal but there has not been any more leaks since I took it into the garage. The fluid level in the differential is fine so it was a very small amount that leaked.
I was driving it a bit hard and was doing a fair bit of steering so wonder if it just got too hot.
Was this an overheating issue?
Was this a pressure blow out, which once it blew made it happy again?
If so how often will it do this?
Is the seal gone but will only leak sometimes when driving more than a few miles?

Second problem is that I seem to be drifting to the left constantly when driving straight. This is causing me to correct about every 50m or so. I have backed off the "braking" drum brake until it barely engages and it still pulls left. I was told it may be a difference in the number of links in the track but they are the same. I wonder if the axle needs to be aligned since I see in the manual that this is done with a spacer. Has anyone needed to do this? How do you determine if it is aligned?