Volvo Penta D4 260 revs

[Stampede]

Hi All,

I have twin Volvo Penta D4 fitted to Volvo DPH outdrives. Both engines will not rev above 1800 and if I do try they become smoky. Its like they both are being restricted.

Any advise please on where should I start to troubleshoot.

Thanks in advance

 

[SC35]

Turbo Boost Pressure - check turbos are free to spin?
Do the superchargers engage or not?
Fouling on props or hull?
Air Filters all good?

When did it last all work properly?

 

[Stampede]

Thanks for the reply,

This boat is new to me last season, so I’m learning about the D4 s .

The boat is just back in the water , so the hull and props are all clean. All filters have been changed ,

Will check the superchargers and turbos when I get back to the boat.

one question I have is why are both engines stopping at 1800 revs. Is the EVC controls telling them to do and can that be re calibrated? On my last boat (KAD 300) I had an issue with the supercharger clutch on one of the engines, but the other used to work fine .

Also would a blocked exhaust elbow cause this ?

 

[SC35]

EVC controls everything on these engines.
Bad boost pressure sensors can cause issues.
But it's very strange that the same problem is on both engines, unless both turbos have rusted up.
Maybe "Volvo Paul" could comment.

Unlikely to be a blocked exhaust elbow.

 

[Stampede]

Went down today and took it out again. Superchargers seem to be engaging. Max revs are 1800 on both still. Turbo readings at 1800 revs are port 20 psi, starboard 30 psi.

 

[SC35]

Still thinking "stuck turbo", but apart from that, I'm out of ideas.

 

[volvopaul]

Went down today and took it out again. Superchargers seem to be engaging. Max revs are 1800 on both still. Turbo readings at 1800 revs are port 20 psi, starboard 30 psi.

You have an issue with boost pressure imbalance, I’d be checking the turbo on the port engine , has any work been done to the intercoolers like strip and clean tube stack ? It’s possible someone has just forgotten to tighten the hose clips between the intercooler housing to the turbo inlet which allows the compressed air to escape .

 

[Stampede]

No work has been done to the intercoolers this year , so it must be the turbo . I will get it checked and I will let you know .

Thanks again for all the advise.

 

[Stampede]

Hi Guys,

Just a follow up on the above issues. Both turbos were stuck and need to be freed . Boat now running great again.

Thanks again for the advise.

 

[volvopaul]

Hi Guys,

Just a follow up on the above issues. Both turbos were stuck and need to be freed . Boat now running great again.

Thanks again for the advise.

Keep your eye on oil consumption as stuck slip rings can snap causing high oil consumption.

 

[Stampede]

Ok. thanks for the advise

 

[nicho]

Ok. thanks for the advise

Am I right in thinking that with the drives disengaged, the engines are electronically prevented from revving
above 1800 rpm? Could there be a link here?

 

[Stampede]

When the drives were disengaged both engines reved to normal range, but turbos did not kick in.

 

[SC35]

Am I right in thinking that with the drives disengaged, the engines are electronically prevented from revving
above 1800 rpm? Could there be a link here?

There is a neutral rev limiter.
This prevents you from properly testing the turbos at the dockside, because if you spooled up the engines enough in-gear, you'd probably end up removing the pontoon.

 

[papparazzi]

Hi Guys,

Just a follow up on the above issues. Both turbos were stuck and need to be freed . Boat now running great again.

Thanks again for the advise.

Hi Stampede, All

I have a similar issue - 2 x D4 260 with DPH and both engines won't go above 1900 to 2000 rpm anymore. If if go from half throttle to WOT there is no change in RPM or engine sound (or smoke). It feels like software is limiting the engines but no errors on the 4inch displays (EVC D). The supercharger boost is shown under boost.

After your and other similar comments I also suspect the turbo to be stuck - question, how exactly did you free the turbo? Was there some deposit build up stucking the hot side turbine to the housing? Was cleaning from the hot side enough or did you need to clean the cold side as well. Did you take out the turbos or cleaned in place ? My boat has super limited space to work on the turbos, so I try to minimize any dismanteling work.

Any tips on the stuck turbo topic would be really appreciated, thanks,

 

[frenzy]

Hi Papparazzi,

Sorry to hear you are having trouble. I have attached 2 photos of mine. Like you the access to the engines is extremely difficult. I have a mechanic who is a lot smaller than me, crawl in the space. Otherwise I would do them myself. He sprayed them and gently moved them until they were free . I’m not sure what he sprayed them with but will find out if you need it .

 

[papparazzi]

Thanks Frenzy,

today I dismantled the exhaust riser from the turbo and inspected the hot side - sadly it's entirely stuck / seized. It could be due to some 6 months without usage in tropical climates with water vaporizing/condensing around the turbine. I can move the turbine for some 2-3 mm with the nut but then its stuck again. Anybody any recommendations/ideas on how to unstuck it? Which kind of cleaner (break cleaner / brick cleaner/oven cleaner / etc) may work here?

thank you very much

 

[papparazzi]

Links to some images

https://imgur.com/a/HnYSVAd