4/22/2016 6:04 AM
A simple field test is after running them for a short period place your hand on the reel motors, the one that has the most internal passage will be hottest. Also as Roland mentioned a case drain test will show the culprit. Use a block of wood and lock the cutting head up, with the case line unhook measure the amount you get in 30 second, times by 2 and see what the manual says is an acceptable amount. Then move on to the next one. If they all check out then you'll need to move to some pressure testing.
Regards,