I got this 500 H.O and the airbox/filter were full of water. So bad that it wouldn't run right. It was running really rich with the black smoke out of the exhuast. The intake snorkel was also ripped open at the carb opening. So I replaced all that stuff, cleaned out the carb, and it runs much much better. However, every so often, it will die while at idle. At WOT down the road it runs great. Has great pull. So, it seems the fuel pump is working properly. So, I thought that maybe, due to the ripped intake snorkel, that the engine had ingested a bunch of dirt, and maybe lost compression. My thinking is that at low RPM there isn't enough crankcase pressure to operate the fuel pump properly. While with the throttle open, it works the fuel pump enough to run right. I did a compression check and it came it at about 90 psi. The engine was warm (not to full temp) and with the throttle open. Any ideas on why it dies intermittently? The compression seems to me that it's where it should be.