problem with carriage not picking up stitches from left to right after clos?

I have a Toyota KS901 machine with all the attachments including punch cards and plaiting unit all of which I have used many times with great success. - The machine has been stored for many years but is in very good condition. Having checked all the settings were correct for plain knitting, I cast on with the closed cast on method by winding the 4ply wool round the needles in anticlockwise direction left to right and cast on knitting from right to left, the manual states that you have to bring the needles forward to E position before returning the carriage left to right for several rows and then continue knitting normally. I am finding I am having to move the needles to E position on every return row which works perfectly. If I don't do this on alternate rows I am experiencing problems with the carriage moving from left to right and not picking up and stitches on the return rows in B position - it's perfect from right to left. I have oiled and cleaned the bed and carriage. I have never had this problem in the past. Could it need a service - or do you have any other suggestions?