Hey all, i know there are a million posts about the ever famous HPDI but i can’t find any that are exactly the same as my issue. Here’s my story:
i have an 06 200 Vmax HPDI with around 700 hours. I recently blew a few pistons so i got the entire block bored, and replaced all of the bearings, pistons, and gaskets. The motor ran great for about 10 hours and now i am back to an issue. When i go to plane out it feels like my motor is almost jumping. When i give it throttle it wants to go then feels as if the key is turned off, and continuously repeats this cycle. It is bad enough where it feels like it would throw you off of the boat if you weren’t holding on. Has anyone experienced this? If so, what was the solution? I recently cleaned the vst, replaced both low pressure fuel pumps, replaced the high pressure pump (with a working pump from on of my other motors). My high pressure fuel pressure seems to be reading in spec (i don’t remember off the top of my head, 750 something?). The only thing i haven’t replaced is my medium pressure fuel pump (inside the vst). Could that be it? Or something electrical i am missing? My friend recently had a similar problem with his Vmax (non hpdi) and his was an 02 sensor. I understand mine doesn’t have this sensor but is there anything similar to point towards? Thank you!
i have an 06 200 Vmax HPDI with around 700 hours. I recently blew a few pistons so i got the entire block bored, and replaced all of the bearings, pistons, and gaskets. The motor ran great for about 10 hours and now i am back to an issue. When i go to plane out it feels like my motor is almost jumping. When i give it throttle it wants to go then feels as if the key is turned off, and continuously repeats this cycle. It is bad enough where it feels like it would throw you off of the boat if you weren’t holding on. Has anyone experienced this? If so, what was the solution? I recently cleaned the vst, replaced both low pressure fuel pumps, replaced the high pressure pump (with a working pump from on of my other motors). My high pressure fuel pressure seems to be reading in spec (i don’t remember off the top of my head, 750 something?). The only thing i haven’t replaced is my medium pressure fuel pump (inside the vst). Could that be it? Or something electrical i am missing? My friend recently had a similar problem with his Vmax (non hpdi) and his was an 02 sensor. I understand mine doesn’t have this sensor but is there anything similar to point towards? Thank you!