Volvo Penta Engine Speed

[kam4182]

Engine power is reduced: Single Volvo Penta Freshwater 300hp marine diesel turbo engine model D4-300 I-F
Accidently hit the throttle forward running about 1400rpm while putting out the fender at the helm door heading into the channel. Immediately backed off the throttle. Now can not achieve greater then 1440 rpm. Used the key fob twice to reset the ignition, no luck. No fault codes on the glass or display. Any advice would be greatly appreciated. Can not locate a Volvo Technician in Michigan.

 

[Bruce Moore]

Bumping post delayed on moderation queue.

 

[BB marine]

In gear or neutral? I ask only because Neutral will not advance Rpm above 1500 rpm.

 

[kam4182]

In gear.

Correction updated information: was running 3000rpm/18mhp when throttle was bumped and then immediately backed down. Engine would not increase above 1850 rpm after that event. Since this incident the maximum boat rpm in gear averages 2250 rpm. No alarms or faults are displayed per page 87 of the operators manual. Repeated EVC resets with the fob have not resulted in any changes/improvements in performance.

 

[BB marine]

Check your boost pressure. This can be seen using the EVC. A D4 common rpm reduction is caused by a stuck Turbo. I’m not sure why a quick Rev and shut down would cause a Turbo to get stuck. The rpm range 1800 rpm in gear WOT seems like no Turbo. If the engine was running 3k then shut down. ( I’m not sure this is what happened) the lack of oil to the turbo bearings could damage bearings. I’m just speculating with limited information. It does sound like lack of boost. The vanes could also just be fouled.

 

[kam4182]

Thanks so much for the quick feedback. Any direction on how to check the boost pressure? Will check the owner's manual.

 

[kam4182]

We found the boost pressure gauge on the glass, did not know we had one. At the dock, throttle only 1500rpm we has 0 psi boost pressure. Tomorrow we will take the boat on the water to see what the boost pressure is under way. Thanks for the direction.
2nd year with a 2019 R31 S still learning.

 

[CaptT]

At 1500 rpm the boost pressure from the turbo will be zero. I generally get 1 pound of boost at approximately 2000 rpms. If your turbo isn't turning you will get no boost pressure and the engine will bog down and not speed up. You can take the clamp off, I mark the location of the clamp with a majic marker or type correction, between the exhaust manifold/riser and the head, the turbo will be visible looking towards the head. You should be able to spin the turbo with your finger, if not your turbo is frozen and will need to be cleared. Many times it's exhaust carbon, ( excess idling), that causes the turbo to stick in a given position and needs to be freed up. Once the turbo is spinning freely make sure you place the clamp in the original position, based on your earlier marking, and torque the clamp to the correct foot pounds, ( unfortunately I don't have my shop manual with me but it can be found in the manual or on line).
Hope this helps.
Terry
PS
If you are not comfortable doing this please contact a diesel engine mechanic.

 

[kam4182]

Your information has helped tremendously can't thank you enough for your timely feedback. Will update as we work this turbo situation out. Kathleen

 

[kam4182]

Update - verified the turbo freely spins, so we are guessing it is a software issue. Of note is the black soot gets every where!

 

[American Flyer]

We found the boost pressure gauge on the glass, did not know we had one. At the dock, throttle only 1500rpm we has 0 psi boost pressure. Tomorrow we will take the boat on the water to see what the boost pressure is under way. Thanks for the direction.
2nd year with a 2019 R31 S still learning.

Could you please expand on where you found the boost pressure gauge on the glass? We have a 2017 D4 300.
Thank you.

 

[kam4182]

How I got the “boost” to display on the Garmin GPS XSV display on the Ranger:
Turn on, at “HOME” select from the sidebar on the right “A/V,Gauges,Controls”
From here select “Engines”, then “Menu” then “Edit gauges Page”
At the top of the screen (above all the gauge displays) touch “Select Gauge to Edit”
I have 3 different displays – I used the one with “Trim” in the lower right and selected (touched) it
Then press “replace data” – select “Boost Pressure” from the menu on the right of the screen.
Then “back” out of the screens pressing the “back” to the Engine display – the gauge you selected should be replaced with the “boost” input.
I hope this helps, it took me a few iterations to figure it out...

 

[American Flyer]

Thank you. Hope you find the problem soon.

 

[Ralf H]

Hi there,

Just chiming in to add that the brief up and down of the RPM during the accidental push of the throttle (I've done that once or twice) while reaching out the window should not cause any issues with the runability of the engine. I also believe it to be turbo related and will be interested in what you find out.

Cheers,

Ralf