Hpdi 300 problem "please help" - The Hull Truth

wadepscott · 06-23-2009, 01:10 PM

One of the 300 HPDI' s on my friends 27 Contender is acting up. When throttling up. (coming out the hole), the engine jumps, sputters and shakes violently, and only goes up to 3400 RPMS. The engine will gradually get up to full power but we have to throttle back and let it catch up. Sometimes it takes a long time for it to get up and run at normal RPM. We brought the boat to a Yamaha mechanic. He thought it was the coil on one of the cylinders. He changed it out along with the plug on that cylinder. We ran it after that and it did the same thing. It seems as though one cylinder is not hitting. We then ran the boat and disconnected each plug wire at a time. All cylinders seem to be firing. Last time out the motor would never get over 3400 RPM's. We tried changing the plugs also, but no change. Anybody have similar problem or experience with this on a HDPI ? Thanks ! Wade
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A1 Outboard · 06-23-2009, 02:59 PM

These engines can have these sympton bacause of several problems. Your tech should uses his computer to check for problems in the high pressure fuel system. The low and mid pressure systems can be checked with a gauge. The condition of the powerhead can be checked with a compression gauge. A problem in the fuel system will cause a powerhead failure which could be the symptom you are having.

mac7769 · 06-23-2009, 04:48 PM

Quote:

Originally Posted by wadepscott

One of the 300 HPDI' s on my friends 27 Contender is acting up. When throttling up. (coming out the hole), the engine jumps, sputters and shakes violently, and only goes up to 3400 RPMS. The engine will gradually get up to full power but we have to throttle back and let it catch up. Sometimes it takes a long time for it to get up and run at normal RPM. We brought the boat to a Yamaha mechanic. He thought it was the coil on one of the cylinders. He changed it out along with the plug on that cylinder. We ran it after that and it did the same thing. It seems as though one cylinder is not hitting. We then ran the boat and disconnected each plug wire at a time. All cylinders seem to be firing. Last time out the motor would never get over 3400 RPM's. We tried changing the plugs also, but no change. Anybody have similar problem or experience with this on a HDPI ? Thanks ! Wade
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Search for threads on VST screens. If its not that, I will eat my monitor. I own two 300 HPDI's, and two 200 HPDI's. Been there, done that on more than one occasion.

wadepscott · 06-24-2009, 09:04 AM

Thanks for the replies guys. Great service that you are doing here. It is much appreciated !