Thanks to everyone for taking the time to answer my questions and moans about the two HengLong tanks I have bought.
Yes, VHR, theSnow Leopard is non S&S as well.
Its my fault for not doing my homework before buyng the Henglongs at a sale in the USA, they seemed a bargain at the time.
I will just have to put up with their limitations and try the suggestions on this forum to make some improvements to them.
The function with the controller that andicog describes, is very similar to my problem, so my next step is to have a look inside to see if there is a problem with the contacts.

Is there a guide anywhere on the forum that shows how to disassemble these tanks.
If the standard batteries are not very good, has anyone a suggestion as to what to buy to replace them.