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2004 200 Hpdi low pressure reading

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  • 2004 200 Hpdi low pressure reading

    I recently purchased a 23 Grady that came with a 2004 200 hpdi. The boat had been sitting for 2 years. So I had the old fuel removed and the tank was cleaned. I replaced the fuel/water separator, all the filters including the metal canister going to the high-pressure pump. VST cleaned, new filter, and seal. I installed 2 new low-pressure pumps. The engine started but would bog down as the RPMs increased. I removed the injectors and had them cleaned and calibrated with the new filters installed. I only took out one mystery filter from the high-pressure pump and replaced the spark plugs. The motor started and would idle, big difference than before. It now revs higher and much smoother. The boat hasn't seen water yet. I hooked up the Yamaha Diagnostics the other day just to make sure everything was in spec. It showed that my high pressure was 35.52 psi. I hooked up a fuel pressure gauge at the VST and I got 50 psi. I know there is no load, but will this motor run at that low fuel pressure. It appears that the motor is running off the electric fuel pump pressure. Also, I noticed my motor does not have a check valve before the two mechanical pumps, the tubing looks factory. Not the issue but want to make sure if it's correct. From what I understand is that the pump has 2 filters, but I just read a post that stated it has 4 filters. Thinking of removing the pump and sending it out to get rebuilt. Any advice would be appreciated.