28 TE 05' Volvo burning 13gph at 3200rpm

[Vickers85]

So I just read that some guys with yanmars are getting around 7-8gph at cruising speeds (3200rpm)

I am getting a whopping 12-13gph at cruise. I have a 2005 28' flushdeck with volvo penta d-6 310.

Does anyone know if this is normal for the volvo or is something not tuned correctly or what? Any help, advice or sharing what gph you are getting along with your engine would be greatly appreciated!

[Tree]

For those RPM’s that’s about right. The sweet spot for the D6 if 2500/2600 rpm where the torque curve peaks. What is your transmission and propellor dimensions? You should be cruising around 17/18knots at 2500 rpm.

[Vickers85]

Not sure but I will find out. All I know its a reverse gear and do not know prop dimensions. Definelty not getting those #s. I am getting 16-18knots at 3200 rpm. I will need to take her out to check what 2500 rpm is getting but I think it's only around 10 knots if I remeber correctly.

[Tree]

I’d take it up with a prop shop - the D6 310 is a funny beast, especially in an albin since they rev so high but the torque curves peaks mid range. My buddy has just bought a catamaran after owning a couple of albins and that has the D6 310’s in it. 18 knots around 2500 and 28 knots around 3400rpm. MPG works best around that sweet spot 2500 rpm.

[Sisu22]

Is the engine making rated RPM at full throttle?

[Vickers85]

The engine is rated for 3500rpms but it will hit 3600

[Tree]

That will be the max rating the ECU will allow the engine to rev to so it’s making rpm no problem. I’m not so sure now that timing the prop to suit will work 100%. It may involve transmission change and new propellor to suit this engine. I would still speak to a prop shop, it may also be worthwhile getting a Volvo dealer involved to get the best from the engine.

[Albin28McKinney]

I am a new member that just joined this weekend. I just purchased about a month ago the exact same 2005 28 TE flush deck with same Volvo as you. I run at 3000 rpm burning 11-12 gph doing 16-17 knots. I do not know my prop dimensions yet. Will be pulling the boat within a month for new bottom job so my numbers may improve a little. Those numbers at 3200 rpms sound correct for that boat to me based on what I have experienced. Will never get 17-18 knots at 2500 rpm.

[Tree]

Just looked at the torque curves for both engines back to back and I would say 2800 rpm would be optimal for the Volvo. The torque curve peaks at 2500 rpm but rapidly drops off where gph goes up dramatically. With the yanmar, the torque peaks at 2200 rpm but stays quite steady through the Rev range with only a gradual fall.

Bear in mind that the D6 is a 5.2 litre engine against the yanmar 4.164 litre. This is why the D6’s are now available up to 435 bhp.

[Vickers85]

I have a 4 blade 19"x22" LH prop

Burning rates:
1200rpms - 5 knots @ 1.25 gph
1950 rpms - 8 knots @ 3.25 gph
2500 rpms - 10 knots @ 7 gph
3200 rpms - 17knots @ 12.25 gph
3500 rpms - 20 knots @ 16 gph

[Tree]

Transmission? My 19 x19” prop gives me ten knots at 2500 rpm with a near enough 2:1 ratio.

[Vickers85]

Transmission is volvo
Reduction gear: 2.04