|Number of Cylinders||5 Cylinders|
|Fuel Delivery||Fuel Injected|
|Weight (lbs/kg)||800.00 lbs / 362.87 kg|
Mission Statement of the Volvo Penta D3-220
This engine is designed to be a lightweight way to deliver 220-hp with high torque and performance at the low end of the rpm range. As such it is appropriate for both single and twin-engine installations in boats that need relatively quick power to get on plane because they are carrying a heavy load or need the range that a lightweight diesel can provide.
This makes it the right size for small offshore fishing boats of all types in inboard, sterndrive, and in both single and twin-engine configurations. It also can be used in smaller cruising boats such as pocket cruisers and express fishboats and cruisers in both single and twin installations.
The D3-220 started out in life and is still used in Volvo automobiles where the model designation is D5. It is a 2.4 liter displacement, 20 valve, DOHC engine with a 5-cylinder aluminum block and head. The basic engine is now in its third generation.
The D3 is a complete family of engines, including both inboard and sterndrive, and the 200 is the highest output.
The D3-220 is going head-to-head with a couple of other diesel engines and with the medium-sized gas engines and even outboard engines in some applications. Its performance, attributes and advantages will become clear in the report below.
Lightweight -- Because the engine block and head are made of aluminum alloy and there are 5 cylinders and not the conventional 6, the D3 has one of the best power-to-weight rations in class.
Common Rail Fuel Injection -- A high-pressure pump generates fuel in an accumulator – the rail -- and is then fed through rigid pipes to the injectors.
Piezo-Electric Injectors -- State-of-the-art fuel injectors that are electronically activated for a variable amount of fuel depending on need, thus insuring optimum fuel economy and clean burning. (See below.)
Variable Geometry Turbocharger -- State-of-the-art turbo design with adjustable vanes inside the house to direct and regulate exhaust gas pressure makes turbocharging effective at low rpms for nearly instant power and clean burning. (See below.)
Clean Burning -- There is nothing worse than a boat transom covered with a thin layer of diesel soot. With time it enters the porous gel coat and becomes nearly impossible to remove.
Volvo Penta uses state-of-the-art piezo-electric injectors in its D3 engines. These injectors are not activated mechanically with a solenoid like conventional injectors, but rather by a stack of 400 ceramic crystals in the injector that enlarge by the introduction of an electrical impulse.
The engine's ECM sends an electrical command to the crystal stack which enlarges and activates the injector needle allowing a metered amount of fuel under common rail pressure to enter the combustion chamber. The unit's injector needle can be opened and closed as many as 10 times per second to maximize control of the amount of fuel going into the cylinders at any given moment.
Max Injection Precision. It’s exactly this type of precision that allows for improved combustion, better fuel economy at all rpms, reduced emissions, and a longer lasting engine. These high-tech injectors were designed for automobiles in order for them to meet stringent emission requirements, and they are 5 times faster than conventional injectors used on gas engines.
The advantages are obvious for both fuel efficiency and more complete burning of fuel.
Variable Geometry Turbo (VGT).
This is a Big Deal. This variable geometry turbocharger automatically adjusts the pitch of vanes in the turbo to regulate the amount of exhaust gas pressure passing across the turbo's rotating blades. The vanes are closed down at low rpms to increase the gas pressure on the turbo blades which spools up the air-intake side of the turbo to cram more oxygen into the combustion chambers.
The VGT Difference. This is the key to the VGT advantage because it is able to quickly increase turbo rpms before a conventional turbo revs up to an effective speed. (In the drawing above, a conventional turbo is always "wide open", so to speak. These units do not have the ability to increase exhaust gas pressure at lower rpms as does the VGT unit, seen in the drawing below.)
In the VGT unit, at high rpms, the normal exhaust gas is under high pressure and the adjustable vanes need only be fully open, acting much like a conventional turbo.
The positions of the vanes in the turbine housing are varied by means of a vacuum generated by a vacuum pump which is driven by the exhaust camshaft.
Fail-Safe Protection. Recreational boats tend to spend a lot of time at the dock and then get worked hard for one or two days and then it’s back into shut down mode. To alleviate any concern, the vanes automatically get exercised at given intervals, while the boat is in its sedentary state.
And there’s one more benefit if the VGT. Because it changes pitch to match demand, we can now afford a smaller turbo on the engine, and it spools up even quicker.
Volvo Penta D3-220 Torque Curve
Note that at about 1750 rpms the D3-220's torque curve rises steeply and rapidly in this high-rpm diesel engine. Because Volvo Penta is a Swedish company it uses the metric "Nm" (Newton Meter) to measure torque instead of foot pounds. (1 NM = 0.737 ft. lbs./1 ft. lb. = 1.356 NM).
Torque rise is the effect that the torque curve displays when loads are increased. The engine is measured on a test bed, run up to full power, and then loads are gradually increased to reduce rpms.
A True Torque Test.
In this test, when rpms drop, it’s not because of the throttle being pulled back, it’s because of the steadily increasing loads put on the engine, all while the throttle is left at the stops. Torque is measured as a force of the engine pushing back against the ever-increasing loads. So with that said, how did this engine do?
Pretty Well as it Turns Out. Thanks to the combination of the piezo-electric injectors, the VGT, and the computer controlled mapping, this engine actually increases torque as the rpm drops. This is an important consideration when operating under the types of stresses that offshore waves create on an engine's performance. It also means, that as in our test, hard turns have little to no effect on bleeding off the engine speed. And this engine will likely perform just the same whether the boat is fully loaded or practically empty.
After Cooler. Virtually all turbo diesels have an aftercooler because compressed air warms up, and the D3-220 is no exception. Coolant runs through a special radiator which further cools and condenses the compressed air before it is sucked into the combustion chamber.
Volvo Penta EVC.
The D3-220 is equipped with the latest generation of Electronic Vessel Control (EVC). This is what allows for digital control stations at the helm, and it’s also easy to add controls elsewhere around the boat, such as for a flying bridge or a docking station at the cockpit. It’s simply another wire run.
Being digital it’s also easy, well relatively anyway, to manipulate the signal between the engine and the control station. Now we can have a host of additional features like trim adjust (PTA) (automatically adjusts the outdrive trim to the boat speed), cruise mode (allows for adjusting the cruise speed up or down in 50 rpm increments), single lever (optional) (one method of synchronization by controlling multiple engines with one lever), engine sync (standard) (another method of synchronization that simple keeps multiple engines operating at the same speeds) and of course our newest friend… the joystick.
And once again, the communication isn’t just one way. EVC allows the engine to talk back to the operator in the form of an in-dash display that is as user friendly as we’ve seen. With a minimal amount of buttons and a scroll wheel, the information on the screen can be added to, subtracted from, and otherwise dialed in so that each operator is left perfectly happy with the informational scan at his or her helm. There is also a 2.5'', 4'' and Glass Cockpit displays.See our EVC video by clicking here...
With an engine producing this level of torque, only the strongest outdrive will do, and in Volvo Penta’s case, that means the Duoprop outdrive. With its twin counter-rotating propellers, this drive makes the best choice for planing boats operating with high-torque engines. On our test boat, we were powering the OceanX outdrive, the highly corrosion resistant version of the Duoprop that incorporates different alloys, paints and other devices.See our OceanX video by clicking here...
Best Power-to-Weight Ratio
The D3-220 packs a lot into its footprint. She measures in at just 33.7” (85.6 cm) long x 32.9” (83.6 cm) wide x 29.6” (75.1 cm) high which makes her well situated for both new builds and repowers.
The D3-220 with DP drive weighs in at 800 lbs. (363 kg) with the outdrive, which makes it lighter than virtually all of the competition in both gas and diesel inboards, giving it a superior power-to-weight ratio. This is made possible for a number of reasons, the fact that the D3's block and head are aluminum is a primary reason.
Why Choose Volvo Penta D3-220 Diesel Power?
We tested this engine in a center console installation. Without even getting to the engine, the benefits are already appealing over outboard power because we now have the whole transom to fish from -- completely free of outboard clutter. But that would also be true of a gas sterndrive system. So that begs the question, why this D3-220 diesel sterndrive?
The Center Console Solution
In the center console test boat, the manufacturer chose to install the D3-220 just behind the helm, right under the leaning post. Because of this location, the sterndrive was driven by a 3' (7.6 cm) jackshaft. This moved the center of gravity well forward giving a lower bow rise upon acceleration, as well as an overall more stable boat. However we’ve seen plenty of applications where this engine was mounted in the more conventional method, directly to the sterndrive.
We tested the D3-220 on an Edgewater 230D center console with an empty weight of 4,400 lbs. (1,996 kg). With 65-gallons (246 L) of fuel, 3 people and the 800 lb. (363 kg) test engine, we had an estimated test weight of 6,195 lbs. (2,810 kg).
We reached a top speed at 3860 rpm of 39 mph. At that speed we had a fuel burn of only 12 gph giving us an unprecedented WOT range of 203 miles. But it gets even better.
Best cruise came in at 3000 rpm and 26.5 mph. At that speed the fuel burn was a mere 6.7 gph making the range 258 miles while still holding back a 10% reserve. That’s 3.5 mpg in a planing center console hull.
At trolling speed, she’s only burning .2 gph where a typical big block gas engine would be burning .7 gph. Even in our head we can do that math and see that it’s nearly ¼ of a gas engine. Clearly this is a money saving engine.
So we have the economy nailed. Let’s talk about the handling characteristics of this engine. We reached planing speed in 5 seconds, accelerated to 20 mph in 9 seconds and continued through 30 mph in 13.9 seconds.
No Bleed off of Power. Where this engine really shines, after the economy of course, is in it’s power and low-end torque. While this may not manifest itself in straight and level runs, it can easily be seen in hard over performance turns where there was absolutely no bleeding off of rpms.
This engine maintained its set speed regardless of the loads placed on it. But as diesels go, this one seemed to handle it better than expected and that’s got a lot to do with the combination of the piezo-electric injectors, the computer mapping, and the VGT (Variable Geometry Turbo). Let’s go through a typical scenario of why and how this all comes together.
A Typical Day Offshore
Thanks to common rail engines we no longer have to worry about a dirty transom -- but we are still concerned about boat control. Inlet waves can be short and steep and we need the power to climb the backs of the sea rolling in or to stay in the trough, but in any case avoid stuffing the bow. Here, precise speed control and the engine instantly answering the throttle is of prime importance. We have no time for a turbo to spool up for the power we need right away.
The D3-220 Solution
As we head up the first wave and the engine responds to maintain rpm. However, this time, the ECM increases the fuel to the piezo-electric injectors and they fire faster in tandem with the variable pitch vanes adjusting the path of the exhaust gases to spin the turbo blades faster, spooling up the unit instantly, thus compressing and pumping more air to the cylinders. Combustion is complete and powerful. The built-in torque rise maintains the engine's rpm and power.
Clearly the benefits of diesel over gas have long been evident. But the benefits of the D3-220 and the advances in technology have taken this power choice to new levels of consideration. The D3 diesel has been used in automobiles for nearly a decade and the current D3 engine is in its third iteration.
What is the Downside to the D3-220? The same thing that is true of all other diesel engines in class -- initial cost. This is largely due to the fact that the number of diesel engines marinized compared to gas engines is quite small as well as the cost of components like turbos, aftercoolers, injectors and fuel pumps. All of this means that the buyer of a diesel engine -- no matter what brand -- has to pay the overhead for not only the block but also to have it marinized, which is considerable.
Nor will the savings in fuel, make up the difference in the cost of the engines. This only pays off in commercial operations, not in recreational boating because far too few hours are put on the engines.
What is the Upside to the D3-220? It has all of the advantages of most diesel engines, some of which are enumerated above. And, diesel powered boats are typically cheaper to insure than gas power.
Scarcity Sells. Consumers should remember that while diesel boats cost more, they also sell for more on the used boat market and usually sell much faster than similar gas-powered boats in class (which are in over abundance). They depreciate less because they generally last longer, so in this respect a diesel powered boat is almost always a better investment than a gas powered boat because they are considered more desirable on the used boat market.