Yeah even with reduced compression it still locked up. I replaced fuel line just to try everything. Hopefully the car is covered for this problem under warranty cos I 've only had it just over a month and havent even used it that much!! The model shop have got the car now so hopefully they can sort the problem out. Its a .28 engine by the way.

mate hopefully the shop sorts it!

Got the car back today and guess wot happens? The pull starter strings comes out and does not recoil again! I took the pull starter off and tested it and it works fine! So I loosened the tension on the screws when putting it back on the car and it recoils now but it will only pull out a little distance otherwise it ends up not recoiling again! At least I can get it started for the time being but surely there must be a problem with the car and not the pull starter?

The problem is entirely the pullstarter, but to make suer you should really clean the oneway bearing to ensure it's free to spin in one direction only.