Just a thought here when buying used engines that can sometimes be troublesome this is not to say you have not alreadys found your problem daddyrabbit but it may be helpful in the future or to others.

When folks are messing with a cranky engine frequently they will try other needle valves even of the same brand, design, O ring count etc. In other words may look identical. But even with all these in place it may not be identical no matter how close it looks. Two of the most important design parameters of a needle valve are the taper grind in other words the angle and length of the taper then last but not least is the thread count of threads. Both of these items will make a hugh difference in how this needle performs with this particular engine.

One example I know of first hand Is the needle valve for the TT 46 pro and the TT61 pro . the part numbers are different but the needles look identical to the eye but the 61 will not function properly with the 46 needle. At least this was the case with the old TT part numbers if not the current Tower part numbers.


John