Yamaha 225 hp vmax hpdi 2004 rattling noise

natecollins1

Seaman Apprentice
Joined
Jun 30, 2006
Messages
37
Hi,

I am working on a 2004 225hp vmax hpdi. It has an occasional rattle/clicking noise at idle speeds noticable around the upper port side of the motor around the high pressure fuel pump and #2 cylinder. It is usually only noticable for a couple seconds when you first start the motor after it has sat for a couple minutes or sometimes when you shift it in and out of gear. I have tried to hold a piece of hose to various parts on the motor (fuel pump, #2 cylinder, etc.) to see if I can hear the clicking noise, but it only lasts for a few times before it is gone. I was not able to hear any clicking noises through the hose. I checked the engine compression and it is 113, 105, 116, 115, 118, 115 psi respectively. The engine is running at no hotter than about 155 degrees F. I hooked it up to the laptop to check for alarms because the new owner said that he was getting a warning horn. It had several overheat alarms. I changed out the water pump impeller, pressure control valve and thermostats. It seems to be peeing fine now even though the water pressure is still slightly low (about 8 psi at full throttle - Yamaha spec is 11). I checked the exhaust tuner and everything looks good with that. I checked the high pressure fuel pump oil reservoir and the oil looks clean and at the correct level. I have reved the engine at different rpms and only notice this noise at low rpms.

Any suggestions on what could be causing this intermittent clicking/rattle?
 
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