A nice project for the Hot Bulb enthusiast?

Tim,

And how are you getting on with that Sabb hot bulb you bought on Ebay last year?

David Mack

From the description it seems that the existing engine is seen as something of an embarrassment, rather than a selling point.

I'm sure it is an embarassment, unless all the missing bits are in a safe place somewhere.

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

Slowly

I've had it running, sorted out issues with the governor and lubricator, but I really want to strip it down completely before doing anything else.

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

Is there not something in the maritime act the states that over a certain length vessel you need a master certificate and I sure that length is 59'

11"

Not, AFAIR, if the vessel is used as a private 'yacht'. Whether or not it comes under that definition is a matter of how it is used, rather than what it looks like.

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

Any idea of what engine it is, Tim?

Regards, Arthur G

Not really, there were a number of Scandinavian producers of that sort of thing, some still going into the 1980s.

Cheers Tim

Dutton Dry-Dock Traditional & Modern canal craft repairs Vintage diesel engine service

Looks like a Hundested.

See this page for a lovely boat which had the last one installed new in 1986.

The only problem with the site is the incredibly annoying flashing text.

Regards,

Chris

Danish fishing boats commonly had Bolinders fitted - which, with their silencers, were often described as 'daleks, with a dustbin under their arm'. This engine would seem to fit that description....

Somebody on UKRW might be interested so cross posting....

Chris D

What a beautiful hull! I've sailed on Viking ship replicas with just that below line shape.

regards

Kim Siddorn

Back in 1974 my parents bought a Norwegian ex fishing boat that had been used for carrying cargo around the Fjords, no nasty fish smell thank god.

Anyway it was 54' long and had a 30 HP Union semi-diesel engine.

Here is a story about the engine my father and I co-wrote and was published recently in a sailing newspaper (The Compass) based out of Bequia in the St. Vincent Grenadines. Its quite long so I am giving you advanced warning. Anyhow I hope those that wade through it enjoy.

First off here is a link worth looking at, unfortunately it is only in Norwegian:

AND IT ONLY TOOK SEVEN MINUTES TO START

About twenty years ago my family and I went to Norway to see if we could pick up one of the old wooden fishing boats which the Norwegian government was pressuring fishermen to sell to modernize their fleet. We found a nice 54 footer with the usual single cylinder semi-diesel engine. The old single cylinder diesel Scandinavian engine was reputedly designed to enable anyone, farmers sons etc, to operate, so they were pretty simple. To start them was another matter. In fact it wasn't unusual to see boats sitting at the dock all weekend just breathing away to themselves while waiting for the next week's fishing to start, particularly in winter as once they got cold they took some time to get warmed up and running.

Ours had a bore of 9" and a stroke of 12". It was said to produce all of 30hp at about 360 rpm. All those tons of metal for just thirty horse, we said?

It stood in the middle of the engine room looking, now that I think of it, a little like RD-D2. It was gray, stood about shoulder height, and had pipes running about it. At the front end was a huge flywheel, about four feet in diameter with a massive rim. In front of that was a big hydraulic pump to work fishing gear and the anchor windlass. Because of the low speed they couldn't use small, high pressure pumps and piping. This monster pump had pipes of at least 2"ID running to and from it.

A true diesel of course works on compression ignition, where the compression inside the cylinder space is high enough to ignite the fuel charge. A semi-diesel needs a source of heat to set the fires going and in fact my own Mitsubishi diesel pick up has heater plugs, the tips of which presumably run red hot when the engine is going.

The cylinder was topped by a combustion chamber, the bulb, which had a thin ring of metal at its base, partly constricting the opening to the cylinder and the edge of which ran red hot while the engine was turning. Combustion took place in the bulb and the expanding gases escaped downwards and pushed down the piston. As the piston finished its stroke it uncovered a port in the cylinder wall which allowed the burnt gases to pass into the expansion chamber?a huge silencer bolted straight on to the side of the engine, almost as large, and water cooled. The nine inch exhaust pipe ran straight from that vertically through the wheel house, providing good heat in winter. These engines needed a large supply of air passing through them, thus the huge exhaust pipe and their almost soft explosions, resulting at times in spectacular smoke rings from the exhaust. To keep rain from blowing in to the open pipe a bucket was usually roped to the top and placed over it at night. This blew off the first the engine fired in the morning. A fresh charge of air for combustion was drawn in through multi tongued steel flap valves in each side of the crankcase.

To start you first undid a screw vent or decompression valve on the side of the cylinder which permitted air to flow in and out of the cylinder. This allowed you to turn the massive flywheel over by putting a large bar into holes drilled in the rim until a mark arrived showing top dead center. You naturally pushed the wheel a little past that point in the direction of normal rotation. On the side of the block was a brass lubricator with ten small copper pipes running to various parts such as cylinder walls, main, big and small end bearings. A small handle sticking out the end was given a few twirls. Other parts like eccentrics to run the water, fuel and bilge pumps etc were given a squirt of oil or grease.

In the meantime you had of course made sure that your air start reservoir was topped up to about 165psi. Anything much under that and you had to be pretty good to get a start! How this was filled will be told later. There were two modern sources of initial heating, the more ancient was a "cigarette" a small Roman candle type firework about as big as your index finger. An internally tapered plug which screwed into a threaded hole in the bulb at the top had a hole into which you jammed the "cigarette". The other source of heat was almost sacrilegious in that it was an open coil of resistance wire which was connected to a

12vdc supply and switched on to glow red hot when needed. The even older engines had a bracket on which sat a huge old Primus type blowlamp. This was fired up and played into a vent in the side of the bulb which heated an area inside to red heat to start the beast. Ours was past that, thank the Lord.

You now had to think about fuel. The single injection pump was eccentric driven and had a manual handle on the top. By undoing a retainer you could give the handle a pump and with luck a charge of fuel blew into the cylinder. The injector was mounted at the very top of the bulb and squirted a charge of fuel which looked like an old Flit gun! .Going back a bit you will recall the small vent which allowed you to turn the flywheel. This now came into its true calling. You gave the fuel pump one good stroke and either lit the Roman candle and hurriedly screwed it into its hole in the bulb while it was spitting out fire and smoke, or you turned on the 12vdc supply to the coil.

In the MEANTIME you had opened the air line which led to the air start inlet valve which was fitted to the top of the cylinder just beneath the head gasket. This was a spring loaded poppet valve and as long as the seal was good prevented the air from leaking into the cylinder until needed. You waited until the charge of diesel you had injected earlier set it self off and blew a small puff of smoke from the bulb vent. With one hand you screwed that shut tight, looked around to see if all was clear and that no wiping rags were sitting on top of the flywheel, then smartly pulled the handle towards you both against the return spring and the starting air to inject a goodly charge of air into the bulb. This had to be judiciously gauged as if you blew too much in you would shoot the piston down and then catch it on the way up again and stop it. On the other hand if you blew in too little you wouldn't give the piston enough oomph to come back and fire on the next stroke.

With any luck at all she would fire the next time the piston came up and off she went. Now it happened at times, due to low pressure or whatever, that the piston would come up, hit the compression, the piston would go down, BEFORE reaching TDC, and she would fire and start running backwards. This was no real problem as it would run equally happily in either direction. All it meant was that the 48" variable pitch prop would be handled "backwards" which is obviously somewhat confusing. So in order to get it to run the right way, you had to slow the engine down to its lowest idle, hold in the fuel injection lever until the piston bounced against compression spinning back the other direction. A well timed squirt of fuel would help send it on its way and she would be running smoothly in the opposite direction. So if all went to plan, there you were, you had screwed the air valve handle shut tight and she was ticking over nicely, and what a tick over it was. Although there was no tachometer, you could count the number of firings and with a second hand equipped wrist watch figure out that the engine was turning over at only 90 rpm!

Now to charge the air receiver tanks.

This was the Prime Directive! If you ever ran out of air you were dead. There were tales of fishing boats at sea having to cut holes in the deck, set up blocks and wrap many turns of rope around the rim of the flywheel. The crew would then run up and down the deck like mad with the rope over their shoulders trying to get up enough speed to get a start, and hoping that there wasn't a backfire which would literally pull arms clean from shoulders! The other more drastic way was to heat the entire tank with the Primus carefully watching the pressure gauge and all the wood around to ensure that you a) Didn't blow up the tank or b) catch the boat on fire.

In the fishing harbours of Denmark the small fueling boats all had air compressors and long air lines to top up boats which had lost their air after repairs or any other reason. This was a free service. We needed it once after the engine ingested a small amount of water which sat on the top of the piston preventing ignition and we used up all the air. So the first thing you did after a start was to reduce engine speed to an idle, hold the air start valve down with one hand and unscrew the retainer above it. Then every time the engine fired you allowed a small part of the combustion charge to re-enter the tanks by letting the air start valve to rise against the return spring limited by the retainer. It became in effect a one-way valve. Care was needed so that you didn't allow too much to bleed past and so stall the engine. Watching the pressure gauge you re-filled the tanks, shut all the knobs and then climbed the ladder from the engine room for a well earned drink.

You had to be careful to keep an eye on that drink, as these high torque -low speed engines induced a formidable vibration in the wooden hulls which were almost entirely trunnel fastened, so that anything placed on a horizontal surface would walk off the edge in a very short time. It was said that the piston was only there to keep the flywheel spinning, and the torque was really wrapped up in the flywheel. When the boat was punching into a head sea, and the revs fell off, the power faded of course and all one had to do was to fine the prop pitch a little, the revs would come back, the torque would kick in again and off she went with a fresh spirit.

In the wheel house, one was surrounded by large bronze polished hand wheels, the two larger ones which controlled the variable pitch propeller and the clutch which thankfully was hardly used as neutral was just zero pitch on the blades. There was also a small wheel for the throttle and even more confusing was a handle which led down to the top of the injector. This varied the spray pattern and was only used when the engine was running near full throttle, the piston would run very hot and a jet of fuel was used to cool it. At lower speeds this same jet would quickly choke the engine causing it to stall. This happened to us once as we were approaching a dock in Denmark, I had forgotten to bring the injector control lever back to the fine spray setting. As soon as I took some pitch off the engine in preparation for going astern, the engine coughed and quit. The solid concrete dock loomed up ahead and all I could do was shout to the rest of the family to brace for impact. The straight wooden stem took the entire force of impact and the sudden stop threw everyone to the deck. Fortunately these Norwegian fishing boats were built for this type of abuse and was none the worse for wear with the exception of a slightly dislodged stem plate. I always wondered why most of these vessels had straight stems!

If you were in any way mechanically inclined, these engines stirred your soul-the rhythmic beat and heavy breathing from the intakes coupled with the soft explosions every time the cylinder fired were like nothing ever experienced from an engine before. These engines also demanded personal care and attention, one had to routinely fill the lubricator, screw down the grease cups and refill them when necessary. The air tank had to be monitored as any small leak in the piping or valves would lead to the dreaded empty tank.

One also tended to caress the engine as the main bearing shells needed to be felt for proper running temperature which was indicative of correct lubrication. Even the shut down routine required more than just the turning off of a key or closing of a valve. After checking the air tank one last time, the lubricator was given an extra turn to provide additional oil to the bearings and then the injection lever was held down until the engine came to a gradual halt. It felt like pulling the plug from the life support system keeping a loved one alive.

Finally the compression release was unscrewed and the engine was barred over to top dead center to prepare the engine for the next start.

The end of an era soon came to an end for these engines and their lovely boats as the fishing industries in Scandinavia were over fished and the governments started paying the owners to get rid of them. Hundreds were broken up or scuttled and by the end of the 70's the days of the Semi-diesel were effectively over. A number of Baltic traders and fishing boats ended up in the West Indies which prolonged their lives but this was but a brief interlude. Now it is a rare occasion to see some of the survivors thumping their way into and out of the harbors but the clear sound of their engines usually precedes them and the smoke rings issuing from their stacks harkens back to an earlier time that unfortunately is all but gone.

The passing of these vessels and their wonderful engines will become just a memory but we are the poorer for it as the modern mind set doesn't allow us to afford the time that these engines required of us. Anything that takes longer than 30 seconds to start and only requires checking once a month is alien to us and not worthy of our impatience.

John and Christopher Kessell

(Massive Snip of a lovely tale)

Thanks for that post Chris, It made for a lovely start to the day. The Norwegian semidiesel site is very useful & leads to a Danish Engine Museum site. Dave Croft Warrington England

Dave Croft Warrington

And also at the risk of the anti ebay posting contingent, do you need one of these to go with it?

David Mack

Hi Dave,

Thanks for the complement.

I was looking back over that site and wow there are a lot of links to Norwegian fishing boat and engine pages. Here is one that has some nice engine pics:

Unfortunately some of the links are broken but click on the svenske motrer link for some nice pics.

Chris