HPDI engine problem

[msteimer]

Hey guys,

I have an engine problem that has been lurking for the past year that I was hoping someone else has (unfortunately) run into and could give me some advice on. The boat is an 01' 265 Express with 200 HPDI's.

Starting about mid-summer last year the port engine started to act up. I would be offshore trolling, pick up lines and be ready to come home, and the engine would not get over ~3500 rpm's. This was the first instance and we decided to just troll in, but after an hr or so, the engine decided it had full power again and cruised fine the rest of the way home. The problem didn't reappear until about three weeks later, only this time it was worse. It would not get up past 2500 or so and was fluctuating between 2000 and 2500 with a constant throttle setting. Problem disappeared again, and then reappeared another couple weeks later with symptoms once again getting worse. After this time it got so bad it would not even start after limping in on one engine.

Hoping that it was a bad filter, we replaced all filters in the engine and still had the same problem. It was hooked up to an aux tank and same problem so pretty sure it was not bad gas. After this point, it was beyond my knowledge so we took it to the marina at the end of the season and had them look at it. They diagnosed a bad high pressure fuel pump and replaced it and ran it twice and said it was fine. Well, I went to run it to our house for the season and after about 10 miles of running perfect, it would not get up over 3700. Again, it gradually got worse as I turned around to take it back to the marina, and by the time I returned, it would not make it over 2000.

Sorry for the long post, but I wanted to give as much info as possible. I'm stumped here and any info you guys could give would help A LOT.

Thanks,
Mark

 

[1st grady]

I don't know much as the HPDI is new to me as well but how about a pinched or colapsed fuel line? Good luck and keep us posted. I had the same issue last summer once for about 1 minute, was at anchor for a couple of hours started to come home and then it acted up, shut down the motors and pumped the bulb a couple of times. then no problem. I plan on replacing filters.

 

[fishingFINattic]

It sounds like they were on the right track.... I would check the other pumps....

 

[KingJ]

Have them check the Vapor Separator filter. It’s a very fine filter and apparently bad gas can clog it up over the course of a few years. I had mine cleaned just the day after yesterday because over the course of a year, it would bog down every once in awhile whenever the bow lifted high enough over a swell, or on take-off. It would immediately regain power, but it got worse and worse until I couldn’t get her above 3500 without her bogging down drastically. I imagine if I had left it for much longer, it may have gotten to what you’re describing…? This did the trick for me and I was almost surprised at how nice she ran on the way home.

If this filter is indeed checked, there is a thin gasket that has to be replaced every time it’s cracked as it swells and cannot be re-fit.

Good luck!

 

[BobP]

Try your question over at thehulltruth.com, vendor sites, Shipyard island marine.

 

[Grog]

You're sure you got to all the filters, isn't there around 5 or so? Did you check or change the low pressure pumps? Did you pull off the fuel housing and clean it out? Sometimes crud forms on the bottom.

 

[gradyfish22]

Fuel pump!!! that would be my bet, next time it does it try pumping the ball, if the engine gets its power back and runs while someone continues to pump it, then your two low pressure pumps are shot. I had that with my HPDI, it would run fine and then after a while would bog down a few rpm's, if I put the engine in idle and sat a few minutes shed run again a few minutes with no problems. If not, the VST filter can be a problem too, but I'd see what happens when you pump the ball, that may help you figure it out. We thought it was the VST, but wasn't, and they aren't the cheapest filter to replace, but it is not that hard to change out, you need the gaskets and all to replace if you replace the filter, I think it all comes as a kit. Also, there is a small mesh that is located at the tank suction, that can clog first and a small amount of crud can really clog the fuel hoses transfer rate from the tanks to engine, check that as well.

 

[msteimer]

Thank you all for the replies!

When pumping the ball it does not regain power at all. We replaced the fuel lines going to the engine thinking there could be air getting in but that didnt do the trick. If I remember correctly we changed out 3 or 4 filters in the engine so we may have missed one, but I'm pretty sure the mechanic replaced them as well. We have not changed the low pressure pumps out, but I'm sure the mechanic will be looking at them now.

King, where is the vapor separator filter? This was the first season we used ethanol so maybe that would have something to do with it being clogged??

We are supposed to check back with them on Wednesday to see if any progress was made so I will keep you guys posted. I'm sure they are more than capable of getting it fixed, but it wouldn't hurt to throw some new ideas their way.

Thanks again,
Mark

 

[KingJ]

Gradyfish22 can probably describe better than I. It’s located inside the metal Vapor Separator Tank (VST) that’s located on the front-right side of the block. Once accessed, this filter can be cleaned, or blown out, rather than replaced. You can Google " Yamaha HPDI Vapor Seperator " and find more info.

 

[catch22]

Did you check/clean your 02 sensor? I had one that caused some serius surging problems.

 

[fishingFINattic]

Since you squeezed the ball and it did not change, I would lead towards one of the three filters - I would focus on the VST....

Rereading this post reminded me a similiar problem when I first got my boat, and I had ruled out filters becaus of the 10 micron racor..... but removing the VST tank, and changing out the screen/mesh filter made all of the differance....

Tim

 

[gradyfish22]

I agree, it sounds like the VST filter from what you are saying and since the engine did not regain power. You can clean the filter, but if I am correct, once you loosen the VST tank to get to it, the gasket never sits correctly so that needs replacement for sure, that tank is under pressure you do not want a leak in it. Has any other work been donw recently? It almost seems like the computer is not allowing you to get up to power, if it is not the VST filter, it may be a sensor not reading correctly. Also, how long since the plugs have been changed? I changed mine alot, they saw about 50-100 hours tops and no longer then one season, I would notice a drop in fuel economy and power after the first trip or two of the new season as fogging fluid would burn through the engine.

 

[msteimer]

I just went back and looked at the work order and the VST filter was replaced. The spark plugs were also replaced at the beginning of the season. I am going to check with them tomorrow...Hopefully there has been some progress made in the past couple days.

-Mark

 

[catch22]

I just went back and looked at the work order and the VST filter was replaced. The spark plugs were also replaced at the beginning of the season. I am going to check with them tomorrow...Hopefully there has been some progress made in the past couple days.

-Mark

Was your O2 sensor checked?

 

[msteimer]

Catch22, the O2 sensor was not checked, so I am going to mention it tomorrow...hopefully that is the culprit.

I will post tomorrow with an update.

 

[JUST-IN-TIME]

a good shop would have plugged it into YDS
looked for codes
then asked when was the last tune-uo u did

then i would have check the 5 basics
fuel
compression
gear lube
spark
battery

than run a fuel pressure check
high side and low side

if they checked, o2, tps, vst strainer
then lp pumps
also the filter after the vst goes bad

i like how everybody here always says, o2 and vst

usally, what i have seen is the filters and lp pumps

 

[gradyfish22]

I agree, Just-In-Time, I did all those tests you mentioned on my HPDI when we had a fuel issue and had them all ran with my mechanic while I was on the boat, we did sea trials on the water too, never threw a code, ended up being lp pumps after they tested fine on his computer software. To check them you need to remove them, that is the only real check. they even ran them in a tank and they loaded fine, that does not work either since engines aren't really under a load and they run different. If they do not pump right, the engine is programed to drop cylinders and run at a set rpm so that you do not ruin the engine hopefully, also as a warning to idle and then shut off. I never had an alarm go off on mine, it just would drop cylinders after running a bit, but pumping the ball did help a little, not a fix though nor recommended to run that way. Still sounds to me like the fuel pumps.

 

[uncleboat]

I have experienced a similar situation on my HPDI 150s. I have never figured out what the issue is but the symptom is very similar. I would leave the dock, the engines run fine, shut the engines for some time, start them up and not be able to get more than 2400 rpms out of BOTH engines at full throttle??? I have tried pumping the fuel bulbs to no avail, what I have found that works for me is simply shutting the engines down and restarting them, they then run fine. Have you tried shutting them down and restarting? My issue does not appear to be fuel, I have checked everything. It is almost as if the engines do not want to fire on all cylinders. This has happened to me approximately 6-8 times last season and every time the stopping and starting of the engines has succeeded. If anyone has an idea about this it would be appreciated.

 

[SlimJim]

I bet its the 02 sensor, I have the same year engines and those need to be cleaned, to replace them they cost about $300ea (from what I have heard ) but they do need to be cleaned. I just had mine cleaned.

 

[JUST-IN-TIME]

I bet its the 02 sensor, I have the same year engines and those need to be cleaned, to replace them they cost about $300ea (from what I have heard ) but they do need to be cleaned. I just had mine cleaned.

JIM WHERES MY TEQUILA