Ranger 31 Throttle Problem

[Maximus]

Hi there friends,

Has anyone had this happen.

Yesterday, I was taking my boat to the yard to get bottom painted. It is an R31 Volvo D4, I went to throttle up and with the throttle full forward at full throttle the engine will not go above 1700 RPM.

I tried cruise control and same thing, I then switched stations and the rear station acted exactly the same, so it is not a throttle mechanical issue. It seems I remember that the Volvo had some kind of “get home” feature that limited the throttle.

Could that be the issue? I have no fault alarms, etc.

Thanks for your help, and I hope everyone is well!

Rob

 

[Kevin Lamont]

Hi there friends,

Has anyone had this happen.

Yesterday, I was taking my boat to the yard to get bottom painted. It is an R31 Volvo D4, I went to throttle up and with the throttle full forward at full throttle the engine will not go above 1700 RPM.

I tried cruise control and same thing, I then switched stations and the rear station acted exactly the same, so it is not a throttle mechanical issue. It seems I remember that the Volvo had some kind of “get home” feature that limited the throttle.

Could that be the issue? I have no fault alarms, etc.

Thanks for your help, and I hope everyone is well!

Rob

Hey Rob,

I would check to see if you have any active warnings, you can see these via the Volvo gauge. From the home screen you want to scroll over to the right till you see "Warnings", select that and it will list out any warnings that are currently active. You can email me direct at kevinlamont@rangertugs.com and I would be happy to help as much as I can.

Thank you,
Kevin Lamont

 

[gwishon]

Also check the turbocharger boost pressure. If the turbocharger exhaust outlet is coked up, the turbocharger vanes/wheel cannot spin, and it will not achieve full boost pressure. Happened to me last fall.

Gordon

 

[BB marine]

Also check the turbocharger boost pressure. If the turbocharger exhaust outlet is coked up, the turbocharger vanes/wheel cannot spin, and it will not achieve full boost pressure. Happened to me last fall.

Gordon

Gordon I was thinking about the issue you had with your engine. Seems similar !

 

[ixlr8]

Also check the turbocharger boost pressure. If the turbocharger exhaust outlet is coked up, the turbocharger vanes/wheel cannot spin, and it will not achieve full boost pressure. Happened to me last fall.

Gordon

I am not familiar with this engine at all. But wouldn't/shouldn't you get an error for requested boost does not match actual boost?

 

[Dale777]

Maximus,

With the D4-300 in my R31, I had exactly the same symptoms as you describe. Fortunately, I was able to get a Volvo certified mechanic to look at it the same day. He found NO code for the problem. But, based simply on the symptoms, he remove the cover for the turbocharger vanes. What he found was corrosion that prevented the vanes from moving.

Since I was up the Caloosahatchee River in Florida at River Forest Yacht Center, I needed a quick fix. So, he scraped the corrosion away with a knife until he could spin the vane by hand. Then he put a drill on it to spin it to high speed to confirm it would work okay at speed. It continued to work for about 6 months, then became a problem again. At that point, I had the turbo removed and re-built. Since then I get a full 28 psi boost at WOT.

 

[knotflying]

I was told by a reliable source that once you free up the vanes you should get a small spray bottle, fill it 1/4 of the way with dawn soap and the rest with water. Start your engine and bring the RPM's up so the turbo vanes start to spin. Then gradually spray the solution into the vanes until there is no more solution. This should clean out any built up crud internally and you should be good to go. I believe it was Brian brown that told me about this.

 

[Cutwater28GG]

are these turbo issues caused by the usage profile?

i.e. not running the engine at hard load for a period of time to get the turbo temps up to max to burn off the crud?

cars with high end turbos used to have turbo timers that would run the car on low revs even after ignition key shut off to allow the turbos to cool down at the end of use.

 

[FWTMD]

If it is in fact the turbo, here is a link to an article that contains a lot of different ways things can go wrong. It's worth a read to see if any of your operating conditions or habits have contributed to it.

And a good primer for the rest of us about what to do and not do.

https://www.soundingsonline.com/boat-sh ... o-charging

 

[Cutwater28GG]

thanks!
From that article

....Chronically running your engine at low rpm for long periods can cause a variety of engine problems as well, including buildup of carbon on the turbine fins and inside the housing. Because the turbine blades must pass within thousandths of an inch of the housing so the compressed air cannot escape, the turbine and compressor wheels must be finely tuned and balanced when installed. Any buildup on the blades can throw the wheel off balance enough to cause vibration and bearing wear, and possibly breakage of the blades. If you are seeing accumulation of soot around your exhaust discharge, you probably have accumulation inside the turbo.

You can avoid this situation by periodically (as part of each day’s run) running your engine at loads close to 80% or even higher. A procedure referred to as “turbo washing” uses a water-based solvent to clean the fins and should be performed by a skilled mechanic. Some engine manufacturers specify a service interval based on engine hours for this procedure....

 

[gwishon]

I was told by a reliable source that once you free up the vanes you should get a small spray bottle, fill it 1/4 of the way with dawn soap and the rest with water. Start your engine and bring the RPM's up so the turbo vanes start to spin. Then gradually spray the solution into the vanes until there is no more solution. This should clean out any built up crud internally and you should be good to go. I believe it was Brian brown that told me about this.

Correct, no code is thrown. I removed the turbo exhaust elbow (not very difficult). Reaching in, one can grasp the turbo wheel and attempt to spin it by hand. If it is coked up, it will not turn or turn only a little and catch on the buildup of carbon (coke) on the walls of the elbow. In my case, it would turn only through about ten degrees of rotation and then catch on a high spot of carbon. I carefully scraped away the buildup with a wooden scraper (sacrificed a wooden kitchen spoon) so as to avoid damaging a vane. As mentioned above, damaging a vane would throw the assembly out of balance, necessitating a turbo rebuild. Once the carbon was removed, I sprayed the elbow and wheel liberally with penetrating oil and reassembled the elbow. The boat has run perfectly ever since, roughly 50 additional hours. I have since added turbo boost pressure to the first page of the Volvo engine display so I can keep an eye on it.

Extended running at low rpm is, I believe, the culprit. I have about 20 minutes of idle speed running to clear the canals on the way to/from Tampa Bay, and I frequently am trolling for grouper in the bay. I now make certain that I spend time with the engine at or near max rpm on each trip out. Shutting down a turbocharged engine without allowing it to cool properly also promotes coking, which is why many owners of turbocharged cars add a turbo timer, as mentioned above. Always allow at least five minutes of idling before shutting down if you’ve been running even normal rpm ranges.

I should mention that I have owned, raced, and maintained turbocharged cars (Toyota Supra twin turbo, among others) for more than 20 years and feel comfortable working with turbocharged systems. Gasoline and diesel turbocharger system specs and operating temperature and pressure regimes are different, though, and I would carefully follow Volvo recommendations on maintenance.

Gordon

 

[BB marine]

Gordon is spot on in my opinion. Idling and low speed operation is not the best way to operate a diesels. The new common rail diesels allow it to be less damaging to the internals but could cause wear along with wet stacking in the exhaust system. This doesn't mean you can't troll or operate at lower rpms. Just realize that after trolling or idling for extended time run the engine up to higher rpm's to get higher exhaust temperatures to help burn off the residues from the wet stacking. If this isn't done over time the exhaust system will have a build up of coke fouling the turbine side of the turbo. The other element of low speed operation, extended idling and trolling, is cylinder wash from unburned fuel. If a diesel is used for trolling or run at lower operating rpms 1000 rpm at minimal load or no load lowering operating engine temperatures for extended periods. The oil change frequency should be shortened or oil sampling to test for viscosity reduction and contaminates in the oil from the cylinder wash.

Actually the D4/D6 is less susceptible to turbo failure compared to the D3. Reason, the D3 has a Variable turbine geometry turbo VTG. The turbo is a great design, it gives good throttle response but it has movable components located in the turbine side of the turbo (exhaust side) the vanes are adjustable to give additional boost when needed. It is controlled from the ECM. If the VTG plate gets stuck it requires turbo removal and the turbo taken apart to clean. Believe me turbo removal is not easy in a Tug or Cut with a D3 R25 SC or R27 SC and C26. I did it for a different reason and the good news was at 400 + hours the plate and turbine wheel were free of coking. The Yanmar 4 and 6 cylinder diesel used in Tugs and Cuts also have controlled boost mechanism called a waste gate. It too can get fouled similar to the VTG. This is not an issue if you are aware of it. There are plenty of threads about this TugNuts and articles available to read on this subject if you do a search.

If you are not trolling or going in or out of an inlet, anchorage or harbor operating at or above 1200 rpm and occasionally running at high speed cruise is all that is needed. Along with making sure you are propped correctly. Prop your boat for the way you cruise. Make sure you are not over propping the engine. Best case 150 rpm above manufactures recommended WOT. Worst case 100 rpm below. FULLY LOADED, If you are running a D3 below 3900 rpm WOT you are over propping it at 1500rpm or any rpm range . If you are running a D4 below 3400 FULLY LOADED you are over propping it at 1500 rpm or at any rpm range you run the engine. If you are lugging the engine you could reduce the longevity of the engine internal components and the turbo. During the SWF rendezvous I gave a short seminar subject "Propping "

 

[Maximus]

Everyone -

Thanks so much!

I was not able to sign on for the last couple days. I'll check the turbocharger immediately. Seems like that may well be the issue.

Rob

 

[bill46]

Need to exercise engine.
Recall mechanic at a MTOA a few years ago telling us to run WOT for five minutes every trip.
WOT not only exercises, cleans turbo, but lets you know if there are any problems, from dirty bottom to engine problems.
We either cruise at 1800 for short trips, or 3100 for longer trips.
We have 2.6 miles of minimum wake canals before ICW. This requires 1000 which warms up and cools down the turbo.

 

[Maximus]

To all my Tugnuts Friends,

I cannot thank you enough for your advice.

I removed the turbo-charger elbow as suggested and looked in . . . Sure enough, the fan was clogged with mega carbon. My bad - low operating speeds.

I brought out lots of different wooden tools that I fabricated to scrape: however, the fan was stuck hard and didn’t move an inch and I sure was not going to force it, so I sprayed it with classic, thick, penetrating oil and waited, slowly it started to move. I “washed” the classic penetrating oil out with WD-40 penetrating oil which was much thinner. An hour and a half later, a million paper towels, and a regal meets, it spun freely. I soaked up all the oil, added Turbo Pressure to my engine view and took her out.

Got her up to full open with correct Turbo Pressure something I plan to do every trip out.

Thanks, thanks and thanks for all the advice, I do not know what I would do without this board!!!

Warm regards for a healthy season and see you on the Chesapeake or Mobjack Bay,

Rob