RedactedNarrative: Vessel one was being towed northbound through the bridgewater channel near sign 11 by vessel two due to experiencing a mechanical issue.  While being towed the operator of vessel one stated he tried to start the pwc and it exploded.  Operator 1 advised he was thrown approx. Five feet into the air and into the water.  Prior to the crash operator 1 advised the the pwc had trouble staying running and when throttle was given to the pwc it would not go forward. Operator 1 advised prior to the crash there  was an issue with a spark plug and fuel was spitting out from the plug.  At the time of the crash operator 1 was being towed by his son on vessel two.  The lake havasu city fire department responded and evaluated operator 1.  Operator 1 refused to be transported to havasu regional medical center and he had no apparent injuries. Photographs of the damaged pwc were taken and uploaded to evidence.com.