When is Diesels sell by date!

Zagato

Zagato

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I thought I had drained all the diesel out of my tank to put fresh in but it seems I only syphoned out half the tank (bigger than I thought at 112 litres). My engine takes a long time to start, 3-4 goes turning it over (don't know if a 2GM20 Yanmar has glow plugs!?) but the original diesel is two years old and if the guy didn't use it much (very possible) the fuel could be even older. Hopefully the 50% mix of new will help it.

The starter battery is new and turns over fine, after the engine is warm it starts instantly, perhaps I'm not giving it enough throttle, the mechanic and yard guy were surprised it wouldn't start sooner though :confused: Engine is OK, no head damage etc. I wonder if they should change the injectors at a service! Done 700 hours...
 
Traditionally diesel didn't really have a use-by date - there are standby generators at industrial sites etc whose tanks were filled decades ago and are still standing by for the power cut that never came. I don't know whether newer formulations, biodiesel, etc have changed this.

I wouldn't worry about it unless you see problems, and even then it wouldn't be my first thought.

No glow plugs on a 2GM20. I have had it take a while to get started when we moved the boat to the hoist in winter, usually just after New Year's Day. Had to spin it up with the decompressors open then drop one cylinder at a time to get going. It always started on the button during the season, so I think it just didn't like the cold.

Pete
 
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Zagato said:
I thought I had drained all the diesel out of my tank to put fresh in but it seems I only syphoned out half the tank (bigger than I thought at 112 litres). My engine takes a long time to start, 3-4 goes turning it over (don't know if a 2GM20 Yanmar has glow plugs!?) but the original diesel is two years old and if the guy didn't use it much (very possible) the fuel could be even older. Hopefully the 50% mix of new will help it.

The starter battery is new and turns over fine, after the engine is warm it starts instantly, perhaps I'm not giving it enough throttle, the mechanic and yard guy were surprised it wouldn't start sooner though :confused: Engine is OK, no head damage etc. I wonder if they should change the injectors at a service! Done 700 hours...
Click to expand...

From this post & the diesel leak one, i think you need to get to know your engine a little more intimately.
 
My 2GM user's manual recommends starting with the throttle fully open and revving the engine before switch off. I find that standing on my left leg while scratching my right ear and mumbling incantations to Susanoo-no-Mikoto (a Japanese god of storms and the sea) usually gets it to start. Once it has started then subsequent starts are one turn of the engine.
 
I have posted this several times when the 'age of diesel' question comes up. I left my VW van at home when living in Holland, after seven years it started and ran perfectly on the same tank of diesel it had in it when I left it.
 
Although the subject of age of diesel is interesting (the first time) more interesting is the fact the it seems the majority of boat owners don't RTFM when it comes to operating the engine - and then piss and moan about their "problems". Even without a book - no switch=no pre-heat. The Yanmars should be opened to full throttle before starting which allows the fuel rack to exceed the normal max and effectively give a richer mixture until the engine fires and the governor kick in.

I'm looking forward to the day when keypad starting reaches the boat market! My mates car has one and I can be in the pub before he's managed to punch in the right number.

Rob.
 
Zagato said:
I thought I had drained all the diesel out of my tank to put fresh in but it seems I only syphoned out half the tank (bigger than I thought at 112 litres). My engine takes a long time to start, 3-4 goes turning it over (don't know if a 2GM20 Yanmar has glow plugs!?) but the original diesel is two years old and if the guy didn't use it much (very possible) the fuel could be even older. Hopefully the 50% mix of new will help it.

The starter battery is new and turns over fine, after the engine is warm it starts instantly, perhaps I'm not giving it enough throttle, the mechanic and yard guy were surprised it wouldn't start sooner though :confused: Engine is OK, no head damage etc. I wonder if they should change the injectors at a service! Done 700 hours...
Click to expand...

The GMs didn't have glow-plugs, though the replacement YMs, do. I never used to have starting problems with my 2GM, except for the first start of the season, which used to need about 25-30" of cranking. I found increasing the starting revs (a diesel has no throttle) to be counter-productive.
I'd be very surprised if the injectors needed resetting after only 700 hours, though lack of use is probably a diesel engines' worst situation.
Usually poor starting is indicative of poor compression, before doing anything else I'd suggest a compression test, otherwise you're trying to diagnose a problem by treating it.
Conventional red diesel at normal UK temperatures is pretty stable - some of the bio additives to road diesel to tend to polymerise and warm temperatures with water present will lead to any number of different anaerobic bacteria - under tropical conditions I've seen a 10l can, left in the sun, become jelly after 2 weeks.
 
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rob2 said:
Although the subject of age of diesel is interesting (the first time) more interesting is the fact the it seems the majority of boat owners don't RTFM when it comes to operating the engine .
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Of course we dont. We're men. We dont do manuals unless everything else fails. After all, your wife didnt arrive with a manual did she, and you still know which is the air intake and which is the exhaust. You even think you know where the throttle controls are.
 
Bosun Higgs said:
You even think you know where the throttle controls are.
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But empirical evidence suggest we don't...

It's not that people hope to run equipment without reading the manual - a well designed interface should make this possible as a large, but when obvious questions are asked about pre-heat and starting which show that no effort has been made to find out for themselves - or even think it through. If there is no pre-heat switch, surely there are no heaters, so look in the manual for cold starting instructions.

Rob.

P.S. I don't even have a Yanmar! ...or a wife, come to think of it.
 
My engine has less than 50hrs and starts easily. Last time out, however, it started fine, but as I left it to warm up while sorting my lines, it cut out and was reluctant to restart. Increasing the throttle got it going but shortly thereafter, it sputtered badly and coughed up a cloud of smoke. From then on it ran flawlessly for an hour or so - some sort of gunk in the diesel? The fuel can be no older than a year or so - the life of the engine.....
 
rob2 said:
Although the subject of age of diesel is interesting (the first time) more interesting is the fact the it seems the majority of boat owners don't RTFM when it comes to operating the engine - and then piss and moan about their "problems".
Click to expand...

Lighten up Rob. The OP has started a few threads and my GOM (grumpy old man) initial response has been to wonder at the apparent naivety but I have repressed it and tried to answer his questions, though the "standing on one leg" was not meant to be serious. I reckon it is better he gets answers to his questions, sometimes conflicting, and eventually he will learn enough to know how little he knows. Yes, the manual asks for full throttle but I think you are wrong about the fuel rack exceeding max, I thought that was Volvo and stop button; if he gets a vhf he might (should) sit the exam for a licence and then he would know about CG forecasts; etc.
 
Well we all start somewhere. I did read the manual about 8 months ago when I first got the boat but have forgotten most if not all of it. I had arranged to be on the boat when the engineer serviced the engine so he could go through the operation etc of the engine with me, unfortunately I had to put the sails on during the same time with the yard manager so we never had a chance to go through it properly. He did of course show me how to start and stop it and I know how to change the filter and impeller from my short Yanmar 10HP days (never needed full power that one to start) BUT when starting this 20HP twin cylinder one it, it took a while and HE said to keep on increasing the lever to more power (so he didn't know to put it on full power straight away either!). When we launched soon after, again we had problems starting her (yard manager & myself this time, probably not enough power again) The yard manager asked if it had glow plugs so that's where that came from but I said I didn't think so I was wondering if it was old diesel hence the question!

Yes your right! I know I don't have to justify my questions ;)

Thanks for all the replies, it's much appreciated. I spend many hours helping people on another forum with questions which to me sound obvious and basic but thank fully no question is deemed as being to dumb by me and other forum members. That's largely what forums are for of course and as has been shown from some of the replies, experience of something can give great tips that go beyond a manual.

Manual here http://j30.us/files/yanmar-manual.pdf I can see why the yard manager asked if it had glow plugs, as said earlier some did/do! A quick google brings up quite a few questions on starting the engine, especially in cold weather - will try the decompressino trick next time. Also came across a dedicated independant Yanmar site just to help people.
 
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