Leaky Pushrod seals

[Cockney Bob]

Diesel Dave has put a thought in my head and now I am not sure.
My greaves engined diesel is now running well and in the last 120 miles has not lost any nuts /bolts or exploded.
BUT it leaks oil from the Pushrod tube.
I have tried all the sealers but still it leaks.
Dave said to me are you sure you have the seals in the right way up.ie top at top and Bottom etc.
I thought I had and maybe still do as the one on the Bottom is straight on one edge and seems to fit in the gap where the Barrels fins are cut away.
However looking at the manual i can not really see if that is correct.
Do any of you out there Know.I am putting this on the Diesel site as well in the hope that someone has a definate idea.
At the moment the top seal is round and seems to fit. The bottom one has a flat edge and has only got a slot through which the push rods go is this correct or should they be reversed.
Just this annoying leak is driving me mad as you know the engines do not have a lot of oil in them to start with.
I have the 412c electric start Greaves lombardini.
Any of you out there know the answer.
Bob