Diesel dies on startup

[Arthur Garfield]

Ok- quite alot to focus in on !
Take a jerry can of diesel and run directly to motor/pump/.
This will tell you if prob in motor.From what you have written-sure seems not engine related.
Forget who said it(HT) external pump from tank to engine best way to go through your filterring sys.
You must realize though,without keel tank MAKEOVER you're fighting losing battle.
I suspect additionally,you'll be well served by an injector cleaner additive which sticks but is effective to run through engine.


All the Best

[yttrill]

I do have a gravity feed tank. I just tried it, and the problem appears ameliorated but it hasn't gone away. Hard to judge. So then it occurred to me: I am starting without glow plugs. So I tried with 5 seconds of glow, and no problem at all. To me this indicates the problem isn't air, but compression or injectors. When the engine is warm, it starts without a problem. When it is cold, sometimes the fuel isn't igniting: the temperature or pressure isn't high enough or the spray pattern in the cylinder isn't right.

My generator never starts without glow, it needs about 15 seconds of glow to start reliably. I'm just used to the main engine starting without glow.

I have a fuel cleaning (polishing) circuit with a fuel pump, and also a generator. I can switch the polisher and main engine to either tank for input and the return line to either tank for output, so I can actually fill the upper tank with the polisher from the keel tank and polish fuel in either tank (but not while the engine is running).

The fuel filters are about 2 feet above the injector pump.

It's useful to have this tank in emergency if there's an air leak, and the polished fuel in it is good because it will go through an extra filter: the tank was originally for the generator, not the main engine, but I have added extra switches. However using it whilst cruising to avoid air leaks begs the question: where is the leak?

Ultimately I have to fix the keel tank, or abandon it, however as a social security recipient I don't have a lot of money for such things: new sails are a higher priority since they're my primary source of motive force, not the engine. I can sail, with difficulty and an autopilot, against a 30 knot wind and 3 metre sea: there's no way I can motor against such conditions. The motor is just too small (80 hp, 30 ton 50 foot boat: underpowered).

There's a lot of good advice in this thread, perhaps it should be saved/made sticky or something?

[Cheechako]

So you are saying it runs and doesn't die now? If it starts at all I doubt it has anything to do with a glow plug. In 35 years of sailboats I've had to use the glow plug to start an engine... even up here in the PNW on one that I can remember. I think the Volvo and maybe one of my Perkin's had glo plugs... but was never used... If a diesel starts it should run.

[yttrill]

It's hard to test: to do a cold start test I have to leave the engine to cool down for an hour. Once its been running for 60 seconds, it starts instantly if I retry.

In all these tests, the engine always fires immediately, while the starter motor is engaged. When it fails it fails within 1-15 seconds, and when it does keep going there's a lot of revving up and almost dying before it settles down. This doesn't happen on a warm start.

So now I have to think about the difference between a warm engine, and hot glow plugs: clearly the warm engine is better lubricated, and the oil is thinner and easier to pump.

I know from prior messing about that the engine barely runs at all if even one of the four cylinders is not firing. When it's not starting right, whilst running it really sound like it's running on 2, then suddenly 3 or 4 cylinders. And there's a lot of vibration.

It's an old engine, there are several gaskets leaking oil (the sump gasket can't be replaced easily, it's too close to the bottom of the boat). The boat was launched in 1998 and the engine was marinised by a company in Brisbane: they use reconditioned engines for that, so the engine is at least 20 years old, probably more.

[h the boat]

Hi Yittrill, at long last it seem we are getting to the bottom of the problem. It would appear that you have two problems compounding each other. The first one, the illusive air leak can be dealt with by the very many suggestions within this thread. The second problem, which with respect has only just been revealed, is that it is rather an elderly engine which may have seen many years or miles in a previous application. I know this series very well and they are basically a very reliable unit, but nothing lasts forever. You will have to bite the bullet, and remove the unit from the vessel for basic overhaul. That means, Head off, Pistons out and new rings. You will probably find that the assumed oil leak from the sump, is not the gasket, but the front or more likely rear crankshaft seal. These normally only wear when the crankshaft bearings become worn and allow a certain degree of lateral or vertical movement... Dont take fright, from your previous posts you sound like a capable person used to the tools. It is not half as difficult as it may sound, and neither is it very costly for parts, they are all available as standard items from most auto spares shops. The same size pistons, bearings,and of course seals are used in many different applications and vehicle models. take the old parts to the shop and let them identify them by size, not brand name... Before fitting new rings, check the cylinder wear near the top of the stroke, if there is a ridge which you can get your fingernail on to, you will have to get a cylinder "HONE" to remove it, then check the top ring, by carefully fitting it into the cylinder, just below the removed ridge. With the ring correctly positioned, there should be a minimal gap between the ends of the ring, about 2 or 3 Thousandsth of an inch, no more. Rings intended for replacement, (Not new production) are usually made slightly oversize, and you may find that you will have to grind off a fraction to fit the bore correctly. if their is a much more pronounced ridge, the cylinder may be worn beyond practical re use and should be re bored, in which case, find another engine from a demolition yard, it will be much cheaper... Have a good look at both the main bearings and the big end bearings, if there is a substantial visable loss of surface, get the crankshaft measured acurately, otherwise just replace the bearings. .. Piston ring wear is very common particularly in marine applications, because of cold starts and relatively short running time. The ring wear will be at least 2000 times more than the cylinder bore wear. Bearing wear is due in the main to inadequate oil maintenance, (old and dirty oil, no filter changes) but as I said previously nothing which is mechanical lasts forever. If you decide to seek a replacement unit, all the ancillaries from your installation can be refitted to the replacement. Avoid so called reconditioned units unless you personally have seen them stripped down. There must be a engine reconditioning firm within reachable distance, ask them for a quotation for a " short engine block" this is the basic unit without the head or any ancillaries... or a demolition yard, see it running in the wreck before you buy.. h the boat.

[h the boat]

A little further explanation, when the engine is cold in a worn unit, the rings are loose and do not give a good seal consequently bad starting and poor running. As it warms up, the rings expand a little and work better... You mentioned that you believe your vessel is under powered. I dont think so, if your engine can give anywhere near its rated output and has a correctly matched propeller, it should be more than adequate for a sail boat configuration. My own vessel, has a displacement weight of more than 280 tons on 30 meters length, at slow ahead, about 4.5 knots my engine is only pushing about 70 HP down the shaft. At 9 knots, it takes about 300 hp. It is all relative to natural hull speed and sea conditions. In poor sea conditions, a vessel under sail will always appear more stable and therefor easily overcoming the conditions than the same vessel under power alone... h the boat.

[JPA Cate]

h the boat,

Wow, that was an impressive post, and you may be way more on top of this than me.


All I was going to suggest is an electric fuel pump for the keel tank to the day tank. To me, if the engine runs okay once it has been started (and perhaps I missed something along the way, if so, I apologize), then the basis of the OP's problem may be nothing more than the fuel drained back to the low down keel. So, if you lift it up by the cheap electric fuel pump to where the day tank is, maybe the problem would go away, for few $$. And he could wait and plan before an overhaul.

Ann

[Jim Cate]

Hey Yttrill,
We were anchored just inshore of you several times last week at GKI. Sorry that we didn't have a chance to say G'Day. Hope that you can solve your engine problem... lots of useful advice so far, and I have nothing to add to the collective knowledge.

BTW, Ann and I were wondering if your boat was previously owned or built by a Dutch chap named Ini or something like that? He now has a proa named "Gaia's Dream" or some such, painted the same red as your boat. Interesting chap and boat!

Cheers,

Jim

[yttrill]

Originally Posted by Jim Cate

Hey Yttrill,
We were anchored just inshore of you several times last week at GKI. Sorry that we didn't have a chance to say G'Day. Hope that you can solve your engine problem... lots of useful advice so far, and I have nothing to add to the collective knowledge.

BTW, Ann and I were wondering if your boat was previously owned or built by a Dutch chap named Ini or something like that? He now has a proa named "Gaia's Dream" or some such, painted the same red as your boat. Interesting chap and boat!

Cheers,

Jim

Yes, Love of Gaia was previously owned by Inigo Winjen. His current boat, Dream of Gaia is in Pittwater, it's a 71 foot Pacific Island Proa capable of carrying 5 tons of cargo at 25 knots under sail with less than 1 metre draft.

As it happens I was in Coffs Harbour when he set out on the first sail.
Glass over plywood with a swinging propeller shaft. Photos on his own website.

Be happy you're not at GKI at the moment, its blowing 25-30 knots, the swell has moved around a bit more it is now partially blocked by the island.

The engine will have to do as is, I cant afford to do anything much about it. I have to get to Sydney (650 nm I think). More concerned about my autopilot: hard to sail this boat without one, especially solo against a SE gale I have a replacement second hand one waiting at the marina, but the weather is to bad to go and get it at the moment.

[yttrill]

Originally Posted by Ann T. Cate

h the boat,

Wow, that was an impressive post, and you may be way more on top of this than me.

Yeah, it was, but it's beyond me at the moment: I would like to get out of the path of coming cyclones back to where I can find some work to buy new sails

If fuel is running back into the tank it has to be replaced by air. However the starting problem also occurs with the tank at deck level which would apply mild pressure to the whole system and prevent any ingress of air unless there were a visible fuel leak (which there isn't). Yes, there's fuel under the engine but I think it's the tank itself which was leaking where it's welded onto the hull: always happens if overfilled and the sea is rough.

An overhaul probably won't happen: I'm already in debt from my last anti-foul. I doubt I'll sail again after I get back to Sydney, can't afford it. But you never know, the long sought after rich Mermaid may yet turn up

[FlyingCloud1937]

You have a seriously bad design.

First the injector pump is not designed as a suction/lift pump, it won't work. It will destroy the IP pump.

Your system was originally designed to use a transfer pump and filter to move fuel from the ballast tank into the day tank, then gravity feed to the engine with a separate filter, if it has no lift pump.

This design accomplishes 2 things, it leaves the weight of the fuel bunker low in the keel, and the day tank provides clean fuel to the engine. The pitfalls are that you have to pay careful attention to the amount of fuel in the day tank. The day tank should be fitted with an overflow into the bunker tank, so that it can't be over filled.

My guess is someone lacking proper knowledge rearranged the plumbing.

Lloyd

Originally Posted by yttrill

Hi, I'm in Australia, it's a Japanese engine.

The fuel filtration and management system has been rebuilt by me recently, and includes a fuel cleaning circuit. The main problem is that the keel tank is crap. It's a steel boat, fuel in the keel, but the top part of the tank is plywood fibreglassed onto the steel. This is a seriously bad idea! There has been enough crap in the tank to completely block the fuel uptake line so at the moment I just have a fuel hose thrown into the tank through the dip-stick hole (no fuel gauge, just a dip stick that doesn't reach the bottom of the tank and can't be lengthened: the tank is 6 feet deep).

There is no lift pump: the injector pump sucks the fuel out of the keel if that tank is selected. The second deck level tank gravity feeds the fuel system but it is only 30 litres and has to be refilled with jerry cans from the deck, so it is useful only for emergencies.

The injector pump recently got refurbished, but bad seals are possible. There was a lot of fuel on the engine room floor, however I have an ongoing problem with the in-keel tank leaking and I assume that is the source of the spillage. Just checked, no sign of a leak near the injector pump or injectors.

[yttrill]

Originally Posted by FlyingCloud1937

You have a seriously bad design.

First the injector pump is not designed as a suction/lift pump, it won't work. It will destroy the IP pump.

Your system was originally designed to use a transfer pump and filter to move fuel from the ballast tank into the day tank, then gravity feed to the engine with a separate filter, if it has no lift pump.
Lloyd

The design may be bad but your guess is wrong, and some of your assumptions are also partly wrong. There is no actual day tank, there is a completely independent small tank at deck level which was installed to run the generator. It is way too small (30 litres) for a day tank.

Secondly there are two reasons NOT to install a lift pump: the first, obviously, is that it is another failure point. The second is that lift pumps are ALSO not designed to suck fuel, they're designed to push it, so they have to be installed at the bottom of the tank, which is not possible if the tank is actually the keel.

Fuel transfer pumps have the same problem: another failure point. The one I have is also not really self priming: it's a gear pump, and it will only lift fuel if manually filled with some fuel first, or is close to the fuel level.

The fact is the injector pump does suck fuel from the keel tank. It may not be good for it but it actually does work.

I don't know who designed the system, the builder certainly made a mess of the tank itself, however the people who marinised the engine are experts and they probably had a say in the design. Everything on a boat is a compromise. It is obviously better to put water in the keel, and fuel higher up (since water is heavier) but fuel generally won't cause the keel to rust away, water will

[Cadence]

Originally Posted by FlyingCloud1937

You have a seriously bad design.

First the injector pump is not designed as a suction/lift pump, it won't work. It will destroy the IP pump.

Your system was originally designed to use a transfer pump and filter to move fuel from the ballast tank into the day tank, then gravity feed to the engine with a separate filter, if it has no lift pump.

This design accomplishes 2 things, it leaves the weight of the fuel bunker low in the keel, and the day tank provides clean fuel to the engine. The pitfalls are that you have to pay careful attention to the amount of fuel in the day tank. The day tank should be fitted with an overflow into the bunker tank, so that it can't be over filled.

My guess is someone lacking proper knowledge rearranged the plumbing.

Lloyd

[Cheechako]

Originally Posted by yttrill

The design may be bad but your guess is wrong, and some of your assumptions are also partly wrong. There is no actual day tank, there is a completely independent small tank at deck level which was installed to run the generator. It is way too small (30 litres) for a day tank.

Secondly there are two reasons NOT to install a lift pump: the first, obviously, is that it is another failure point. The second is that lift pumps are ALSO not designed to suck fuel, they're designed to push it, so they have to be installed at the bottom of the tank, which is not possible if the tank is actually the keel........

I'm sorry but this is just patently wrong. Probably 95% or more of diesel cruising boats out there have a lift pump on the engine.... not in the tank. Most often this is above the tank as well. Your premise that pumps push better than suck is true... but that doesn't mean they don't suck for many years without issues....

[yttrill]

Originally Posted by yttrill

Everything on a boat is a compromise.

Just to emphasise: the engine is too small for the boat, 80hp isn't enough for a 50 foot 30 ton boat in blue water conditions.

And the keel tank is only 300 litres, which isn't enough to go anywhere motoring.

The prop was also undersized.

The exhaust pipe came out right in your face in the cockpit (the system is keel cooled so it has a dry exhaust).

It's a compromise, probably motivated by cost: if you're good sailor cruising in blue water the engine is only used anchoring, in close quarters berthing in a harbour, or in an emergency. The saved money is better spent on backup sails, and the wear on the injector pump isn't a concern if you're not planning on using the motor much.

I've fixed several of these issues (replaced the prop, rerouted the exhaust, added an extra 300 litre fuel tank, added a fuel polishing circuit, and allowed the generator tank to feed the main engine as a backup).

I will probably discard or rebuild the keel tank, but right now my problem is simply to get out of the tropics back to my home base 600 miles away solo before cyclone season. I have no money to rebuild the engine, if I did have I'd spend it on sails or a second autopilot.

It's a compromise. The main fuel line in the tank blocked completely so I just threw a fuel hose into the tank. It's not ideal, but it works.

If I were rich .. I'd buy a helicopter instead