Hi, I have an old 743. I can get the boom and tilt working but when I try to travel either side in either direction the pump starts wailing and it will stall the engine if i dont let off. I drove it onto my trailer a week ago down in vancouver where it is much warmer and above freezing and towed it up the interior of bc where i live and it has been below freezing since I brought the machine here. The machine sat for a number of years before I acquired it. Is there any way that the park brake could freeze on if there is water in the chain case? I have completely removed the park brake linkage and pryed the pedal all the way towards the back of the machine. Currently I have a magnetic heater on the chain case, I'm hoping something froze up in there but it's really just a crap shoot. Unfortunately my shop isn't big enough to stick the trailer and machine in the heat. Anybody have any other ideas? Are there any safetys to lock out travel that I'm overlooking here? Thanks Spencer