06' 250 HPDI troubles still.

[Snapinjaws]

Guys I made a post a month ago about my engine only running 5400 RPMs and 64.9 MPH WOT. Well suggestions were changing the filters especially the Canister filter between the VST and the HP Pump. Yeah Well, they got changed today and still nothing. What I did notice at WOT was a slight jerking. Almost like something else is restricted or its not getting enough voltage. It's slight but it's strange. Almost like something it's a spark issue maybe. I changed the plugs as well. First run is always better than all the rest. First run was 5700 RPMS and 66.3MPH. Then it dropped down to the normal numbers in my last post. I'm seriously pissed. I've had issues with this engine since I got it. I need some help with this issue guys. Thank you.

[Chisco]

Ignition coils and injectors are next. A coil can be bad and it won't be picked up on computer.

[Snapinjaws]

Alright. Is the service something I can do or just take it in. If so is it really expensive?

[Chisco]

I had my injectors cleaned at the shop....I believe it ran $150-200 if I recall correctly. The ignition coils are relatively easy to replace. Just depends on whether you plan to troubleshoot using just one new coil. If so, could be a little time consuming running the motor after each change.

[Snapinjaws]

Ok thank you very much. I'm thinking it could be one of the other concerning the slight jerking at WOT.

[Charlie206]

Which filters did you change? There are 3 under the cowling, not including one in the boat and not including the baskets at the high pressure pump. Any of these could be the problem. The strainer is the most likely but not the only possibility.

[onewalker]

I have the same issue.. big service done including injector filters and 4 hidden filters in HP pump..worked for others, not me though. From what I have been told, been suggested and all the research I've been doing lately, I'm checking the coils next and hope I have a bad one... I plan on keeping folks posted here.. please continue to do the same.. maybe we can both get our issue resolved soon.. I'm tired of my 250 HPDI on a 20i only doing 59 MPH which it use to do 70... it's freaking crummy.. I feel your pain man.

Good luck

[Steve 187]

Compression?

[Snapinjaws]

I have 108 across the board on compression. I changed the Canister filter, the clear cased filter. That was it. I have the basket filters for the pump and Injectors but was told they rarely ever get clogged and not a big issue. Where is the filter in the boat?

[Snapinjaws]

I was asked about the stator. Onewalker, have you had that checked at all? And do these usually go on these engines.

[wbrown]

I have 108 across the board on compression. I changed the Canister filter, the clear cased filter. That was it. I have the basket filters for the pump and Injectors but was told they rarely ever get clogged and not a big issue. Where is the filter in the boat?

Not true for the high pressure pump. If that pump has never been opened and basket filters replaced, I would try those.

[Snapinjaws]

Ok, thank you very much. I appreciate that.

[Charlie206]

There is also a filter, actually a screen, inside the VST under the fuel pump. The pump itself will generate trash and that screen catches it. If it is dirty you will lose fuel pressure or volume to the high pressure pump. I would go there first, and check that screen. If it is OK, I would move on to the "secret" basket filters in the HP pump. Only after doing that would I look for an electrical problem considering you likely do not have a spark checker. If the filters in the HP pump are clogged, it would be prudent to change them in the injectors also unless you have already done that. Japanese electrical parts are highly dependable and the HPDI is known for REQUIRING fuel system maintenance. You don't know if there is a fuel filter in the boat? Open the battery compartment and look around. If there isn't one, once you get the outboard lined out you need to add a 10 micron water separating filter. It will save you a whole lot of problems with the filtration system under the cowling.

[Snapinjaws]

Ok. I just bought a fuel water separated that mounts inside the boat. I will do what is recommended. Thank you very much.

[Charlie206]

Also, next time you run it, as soon as you see it will not reach its known WOT rpm's and you feel that hesitation, shut it down and trailer it. Those are symptoms of fuel restriction, and that condition will kill a powerhead at high speed.

[Charlie206]

I have the same issue.. big service done including injector filters and 4 hidden filters in HP pump..worked for others, not me though. From what I have been told, been suggested and all the research I've been doing lately, I'm checking the coils next and hope I have a bad one... I plan on keeping folks posted here.. please continue to do the same.. maybe we can both get our issue resolved soon.. I'm tired of my 250 HPDI on a 20i only doing 59 MPH which it use to do 70... it's freaking crummy.. I feel your pain man.

Good luck

What are your WOT rpm's? Speed has little to do with diagnosis.

[Snapinjaws]

Thanks charlie. I appreciate it very much

[Charlie206]

I have 108 across the board on compression. I changed the Canister filter, the clear cased filter. That was it. I have the basket filters for the pump and Injectors but was told they rarely ever get clogged and not a big issue. Where is the filter in the boat?

I misread this earlier. I thought you said you changed the canister and clear cased filter. My bad. So, I assume you did not change the "strainer", the metal filter between the VST and high pressure pump. If not change it before doing anything further, in my experience it's the most likely culprit. You can do it yourself, read the stickys pinned up top here.

[Snapinjaws]

I changed the Metal filter between the VST and the pump. Still same outcome.

[coybock]

Have a 2009 250 HPDI on a Z21 Ranger. Powerhead rebuilt a year ago. Achieves 63mph Max. It's Gator Hulled. Changed prop to a Tempest. WTH is it not hitting 70?