12th April 2009
Time for a change of heart. Author Billy Billson
Time for a change of heart!
It is hard to keep up with the pace at which the electronic world is changing our lives. It seems that as soon as you have made the decision and purchased a new electronic devise for you boat, it has been replaced by another model, with more features, and abilities than what you have just installed.
The advancement of the electronic world has also instigated the many changes that we are seeing in marine engines. Through the seventies being trained as a marine mechanic, I saw the introduction of electronics into the outboard motor industry, with Mercury marine introducing electronics into their ignition systems, of cause it had to come with a catchy name, and many of us would remember the thunderbolt ignition logo on the front of the black outboard, and the literature marketing this new fandangle system, bragging about 40,000 volts at the new permacap spark plugs and the end to plug fouling. Before long Petrol inboard engines started switching to electronic ignition, and the start of electronics being an integral part of a marine engine had begun.
Diesel engines though, which rely on no spark to ignite the fuel air mixture, and there already renowned reliability, remained stagnant in there basic configuration. Only the enhancement of turbo charging after cooling, and indirect injection, made the common diesel engine something more than it originally was.
The slow introduction of electronics prior the now well known common rail system had its share of problems. There were stories going around of motors just stopping for no apparent reason at all and could not be restarted, boat captains who had tickets covering all types of marine engineering had no idea of were to start to look. The computer system or black box as they were commonly called was having a hick up, The easy fix was to just reboot it, you know turn the power off and back on again. But a little scary if you were trolling the edge of the drop off on the Great Barrier Reef, within meters of the breakers, and 25 knots of trade wind on your beam. Confidence was lost due to this fact, as a boat Captain worth his salt could normally keep a motor running, even if he did have to use a bent hook, liquid steel and a bit of 040 wire.
Just before the introduction of common rail diesel engines and electronic fuel controlled and computer controlled engines, engine manufactures were having trouble dealing with the strict emission control regulations especially in the European Market. Fuel pump dampening to restrict the fuel rack movement, until the engine received sufficient air from the turbo boost, made engines very non responsive. And driving these engines on hot fish was nothing more than frustrating. Great responsive engines such as 555 big cam Cummins, 3208 Cats, and the 92 series Detroit’s were becoming a thing of the past, and so was the smoke signals we received when these engines were given the power sometimes needed for maneuvering.
Computers are now common on all marine diesels, whether it be a common rail system engine, or one of the other combined electronic and mechanical systems.
So what is common rail, as the name suggests there is a common rail that acts as an accumulator to feed fuel to all of the injectors. Fuel is supplied to the rail by means of a high pressure pump, which can obtain fuel pressures up to 2000 bar (over 29000 psi). This pressure is regulated and monitored by the electronic diesel control (computer or Black Box) Electronic injectors are also controlled by the electronic diesel control as to the timing and amount of fuel supplied to the injector. Some injectors such as the Piezo type allow for very short and rapid fuel delivery, with up to 7 injection cycles per engine combustion cycle. All of these components are interconnected by the electronic Diesel engine control unit, and gather a seemingly endless source of information by means of input sensors such as, engine speed, oil pressure, engine temperature, fuel temperature, throttle position, top dead centre reference, rail pressure, start of injection, charge air pressure, charge air temperature, and fuel temperature. Well what does all this mean and what does it give me compared to my old faithful clunker? Well here it is in a nut shell, much greater fuel economy, largely reduced exhaust emissions, greater power to weight ratio, cleaner starting, less noise, and a much more responsive engine, than the dinosaurs of yesteryear.
The electronic world has also introduced variables to some existing fuel systems, not all new technology engines utilize the common rail system, but have opted to design a system, which best suits the engines requirements. The Celect fuel system by Cummins is one of these systems, and is used in there popular QSM11 range of engines. CELECT is a full-authority electronic fuel system. That utilizes unit injectors with high injection pressures and infinitely variable timing to improve the fuel combustion process for lower emissions while providing improved performance. Engine timing can be advanced during starting conditions to reduce smoke and improve transient response, as well as, retarded at rated conditions for overall maximum emission performance, fuel economy, and durability. The Celect unit injector design utilizes electronics as well as an optimized camshaft to increase midrange fuel pressures to high injection pressures.
My boat Viking 11 reached her 10th birthday last August and it was time that I made a very big and of cause expensive decision. To rebuild or repower! Being a charter boat operator it is imperative that I have reliability and with the sort of hours that were starting to build on my original 183TE92 MTU’S, and my projection on how long I plan to operate the boat, a choice had to be made. At first I was going to rebuild as I held many parts from another motor that were in good shape to assist in this, and I would do the work myself in the off season, definitely the cheaper way to go. But I was being bombarded on information on how great these new technology engines were, and as we all would remember the rising price of fuel last year, had us all wondering what the future would bring.
Unfortunately for whatever reason some new design engines turn out to be lemons and spend more time with the hatches up than down, spending the amount of time I do on the water I get to here the worst of these, and it often takes more hours than the average private boat does a year to bring out the inherent problem issues in some new engines. Of cause the engine companies are very reluctant to wave the flag, and you really have to have your ear to the ground to become aware of lemon models.
One motor company which I have heard very little complaints with there engines is Cummins and over the last 5 years the QSM11 Range of motors has being used in many of the Charter boats up on the reef. O’Brian Boats of Townsville has being using them exclusively in there 47ft sport fishers which are primarily built for the Cairns Marlin fishery
These boats do the miles in various conditions to truly test an engine. And if you speak to any of the Captains who run boats with these engines, they cannot praise them enough. The big thing that kept me envious, was what I was hearing about there fuel efficiency, to me it sounded nothing more than unbelievable.
So after a couple of meetings with the sales staff at Cummins Mercruiser Diesel at the Gold Coast that big decision was made. Two QSM11 were ordered, and plans were made to pull Viking 11 out of the water for a major engine room Refit. With the help of mate Brett Alty and Crewmen Peter McRae, I would take on the project of removing the old MTU’S, retrofitting the whole engine room, and installation of the new Cummins, so that Viking 11’s engine room would again become a glamour to behold.
It was a exciting feeling, knowing I was giving this Frank Woodnutt classic custom 46ft sport fisher a new lease of life, with another 100hp a side and all the new technology that was coming with the package. One thing about a epoxy built custom boat is that they can become ageless as long as engineering, electrical, and electronics are kept to current technology, and of cause the same can be said about some of the classic production boats of the past, that in many cases are better built stronger and have better sea attributes then some of the current lightly built models of today
We had the old motors and generator out in the first day, and started the process of removing all old engine harnesses, instrumentation, fuel lines, and virtually everything that was not going to be part of the vessel anymore. As I was involved in the building of Viking 11 in 1996 and 1997, and now having a second go at the engine room, the old adage if I had the time again I would do it different came into play, and there were things that I did want to do differently. But first the fared two packed engine room had to be bought back to its original condition, over the years through necessity I have picked up the spray gun, and although I wouldn’t advertise myself as being a spray painter I manage to keep my own boat tidy. The gleaming snow white awl gripe finish set the platform for all of what was next.
The old copper fuel lines were replaced with stainless tubing and blue stainless braided flexible lines. The Racor primary fuel filters were re-sprayed and repositioned forward of the engine room as all the service filters on the QSMII Cummins are mounted forward. The configuration of the fuel system was changed so as the rear tanks only had suction and return lines through the fuel manifolds, and a transfer pump bought fuel from the forward tank to the aft tank via the return fuel manifold, a much simpler system.
Copper bilge piping was repainted, and a new engine driven pump installed and new piping fabricated to match new engines and existing bilge manifold. The Two way 240volt oil change pump was also mounted forward close to servicing areas of engines, and a simple manifold installed to allow quick oil changes of engines, gearbox, and generator. Flexible red Ortec hosing was used from this manifold suitable for oil and suction, contrasting the colors of the other piping in the engine room.
The Cummins electrical harnesses are have all push in male and female connections and a well marked to make it quite simple to connect. It is a tidy brilliant system that is easy to follow, our biggest hurdle was accessing the archways and getting the wiring to the bridge, overhead consul, and tower, an extra pipe to the overhead consul from the bridge consul had to be installed but this added an extra handrail as well and does not look out of place.
To keep costs down I revamped the old ZF gearboxes which were rated to 600hp which was the rating of my QSMII, It also made the fabrication of the new engine footings a simple process. All of the newly fabricated footings were also sprayed with two pack, and the Barry mounts used by Cummins were installed ready for the new engines.
My Mather’s electronic controls were still used, with no changes needed for the gearbox cables, to the boxes. Cummins supplied the adaptor components which the throttle control cables connected to, changing the mechanical movement to a electronic signal to the engines computer, as well as engine synchronization.
The generator was moved from forward in the engine room to the aft, which made all the service areas on the Cummins much more accessible, and moved weight aft, another benefit to the boat, and made the service areas of the Cummins more accessible as for the generator.
The original fiberglass exhaust system and pong box meet Cummins specifications, so as all that had to be changed there was the inlet tail repositioned to meet up with the new exhaust outlets, and the old holes blanked off.
As we were running the same boxes and the Cummins top end was 230O rpm compared to the MTU’S 2100 rpm it was calculated that only half an inch of pitch would be added to the four blade Teignbridge propellers.
We had the QSM11 Cummins being lowered onto the mountings 3 weeks after the old motors had been removed, and after some other paintwork on the boat and general yearly maintenance, had Viking 11 being lowered back into the water one month after it was lifted out. Final engine alignment was carried out and the Cummins technicians were notified that we were ready for a fire up.
It’s a great feeling after running a boat for ten years with a certain power plant, to than have that boat repowered with more horse power, a different torque curve, and a whole new feel about the boat. Of cause it was a exciting moment when the QSM11,S first came to life, the note out of the Two 8 inch exhausts sounded totally different than the previous engines, They almost sound like a Ford big block V8, a very crisp note, and like a petrol engine their was no smoke. The Cummins tech connected his laptop to the engine sensors, and we prepared the boat for its first sea trial.
The motors are set to idle at 600rpm and are always in sync, they also have a low idle setting at 550 rpm, 2 cruise settings, and a on off switch for the synchronization. We idled out of the marina and the boat and motors felt smooth and the boat had no low speed vibration, which was the first plus as a comparison, the distance between Gold Coast City marina and the Broadwater is a long hall at the best of times at the maximum speed of 6 knots, but my keenness to test these new engines made it seem that little bit longer. The last no wake sign passed the port side, and I pushed the hammers down, The QSM11,S leapt to life and Viking 11 jumped out of the hole quicker than it had ever done before, no smoke no turbo lag just clean response, another big positive comparison. I was starting to see what all the talk was about.
Cummins diesels, have formed a alliance with Mercruiser and use their Smart Craft technology for engine monitoring, a daylight color screen monitors everything you could ever want to know about your engine, from the basic temperature and oil pressure, to fuel usage, engine load condition, and engine room ambient temperature, to name just a few. Viking 11 got two 28.5 Knots into 20knots of southerly and the RPM reached 2350 at 95% load there was possibly room for a little more pitch, but as the boat is used for live aboard charters on the reef, and has to carry a fair bit of gear I thought we were on the money.
After all the testing that was required for the engines to be signed over, I was starting to realise just how different the boat felt and responded to how it was previous. My trip to the Barrier reef for the Marlin season, showed a comparison in fuel burn that was remarkable. Here are some of the statistics.
Viking 11 before refit fuel burn. Viking 11 after refit fuel burn.
8.5 knots. 900 RPM 24 LPH 8.5 Knots 875 RPM 16 LPH
20 Knots 1875 RPM 145 LPH 20 Knots 1850 RPM 128 LPH
21.5 Knots 1900 RPM 154 LPH 23 Knots 2000 RPM 146 LPH
Cruise for previous engines Cruise for Cummins engines
25 Knots 2150 RPM 200 LPH 25 Knots 2100 RPM 168 LPH
Full throttle previous engines Top end cruise Cummins
28.5 Knots 2350 RPM
Full throttle Cummins
Viking 11 has now clocked up over 1200 hrs since August last year, and the decision to repower was the right one. For a sport fishing charter boat operation it means I am able to do extra days on the same amount of fuel I would burn previously. Other major advantages include, Less engine Vibration at low speed, No smoke, No soot over boat or in cabin, Paint work lasts longer, minimal pollution to water and atmosphere, Happier clients.