Starting an old diesel.

jamie N

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My single cylinder, 10hp diesel engine starts OK, which is good. It doesn't have glow plugs, but does have a decompression lever.
My starting procedure is to use the 'fuel bulb' to pump fuel into all areas of the system, then pull the decompressor, set throttle to max and press the engine start button. Let the engine turn 10-15 revolutions, then release the decompression lever. The engine has started 'pretty much' immediately each time, before I then close the revs down to a stable tickover,
Given that the temperature has been hovering close(ish) to zero for much of the time, I'm quite happy with this.
I give the engine the initial decompressed revolutions to get the fuel flowing, and to get the oil circulated, as well as allowing the starter motor to get up to speed.
The engine's 30-40 years old, and in most ways as traditional an item as can be had, with nothing that'd surprise any of us.
Is my starting procedure fairly standard stuff for other similar engines, and are glow plugs an advantage, or a complication?
 
If it starts easily in this cold weather then I would say the engine is fine without glow plugs and leave well alone.
 
What!!!!! You have a starter motor!!!!!!

You lucky bugger!

I used to hand wind several much larger marine diesels - Lister twin and triple air cooled jobs. On full size canal narrowboats.

A bloke called 'John the Welder' who could repair magnesium alloy JAP Speedway engine crankcases using a generator powered by an air cooled Lister painted in Navy Grey. He said it came from a battleship!

To get that going on a cold day we had to take off the air cleaner gauze and suck flames from a diesel soaked rag tied to a stick into the engine while winding the starting handle flat out with the decompressors lifted. They were dropped one at a time, the handle being turned flat out all the time. As each cylinder started firing it got easier to wind.................................
 
Sounds fine (but then it's only 30-40 years old! :)).

With experimentation you may well find it doesn't need full 'throttle' to start. (It would probably prefer not to be revved too much on initial start up.) I think about third 'throttle' would be typical, but some require the lever to be pushed to max first (to operate primer for cold start) and then pulled back to the relevant starting position before operating the starter motor. Check the manufacturers recommended starting procedure in the owners handbook (most available online somewhere or other), or tell us what it is and someone here will probably be able to advise.

You may well also find it doesn't usually need the decompressor operated to start, unless the battery's a bit feeble or you are trying to hand start it.

You shouldn't need to pump the fuel bulb (unless it has stood for a very long time, you have leaks, or have changed the filter or fuel lines). The entire fuel line should remain full of diesel.

All IMHO.
 
That sounds just like the way to start a Yanmar 1GM when it is cold. However its should not be necessary to drop the decompressor, but just to turn the engine over with the lever up to circulate oil which has the effect of increasing compression by oil getting behind the rings. Then lower it before pressing the starter again. as frequent dropping the lever for starting can lead to wear on the valve stem Should not be necessary to use the pump as the fuel system should be primed already - the only reason for having a bulb is that it helps with bleeding, but once the system is bled it does not do anything. pushing the control lever to full over fuels the engine to give you that first big bang to get it going, although when warmer you should not need to do this so much
 
Spray 1/2 a can of Start ya Bastard into the air-cleaner. (I think it was Paul Rainbow who gave us that tip on another thread: correct me if I am wrong) ?
 
Spray 1/2 a can of Start ya Bastard into the air-cleaner. (I think it was Paul Rainbow who gave us that tip on another thread: correct me if I am wrong) ?
Not a good idea, washes oil off the cylinder and loads up the cold engine by 'knocking' i.e. pre-ignition. If it starts easily doing what you do, then don't worry, apart from Tranona's comment on the valve wear. Lister start-o-matic gensets used valve lifters to get going and didn't have a problem, but they were heftily built for the horse power. I lived with one for several years off grid and it had been there for 30yrs in daily use.

Apart from that, how would you fit a glow plug? The old Perkins one that vaporized some fuel in the inlet , just under the air cleaner is a possibility, if a bit crude.
. Can't see you drilling holes in the head to fit one in the combustion chamber......
 
Apart from that, how would you fit a glow plug? The old Perkins one that vaporized some fuel in the inlet , just under the air cleaner is a possibility, if a bit crude.
. Can't see you drilling holes in the head to fit one in the combustion chamber......
Oh no!!o_O
No the 'plan' isn't to fit a glow plug, but was merely a muse and a comparison to my starting procedure, where the idea of turning the key and allowing the 'engine' to sort out how it wants to start crossed my mind.
The full throttle thing is from the manufacturer though, but I should've mentioned that the throttle is closed immediately it fires.
Tranona's comment was interesting, as I'd not thought for a second about the oiling of the rings to increase compression.
Pumping the fuel bulb is a personal thing where I simply feel it's better, without any proof or justification at all, as well as allowing me to think about what I've forgotten; a habit that's all.
Allowing it to turn over that many times is again personal, just to get the oil around the engine.
I've used "Start yer Bastard" before, who hasn't, but not on this engine which was rebuilt and fitted 23 running hours ago!
Thanks for all of the comments which really are a help!
 
I used to do much the same on my old engine without glowplugs, except that I never used the decompressor. It always took a bit of churning in cold weather, but that got the oil pressure up before it started. I'd say that if your technique works, try it without the decompressor. If it starts, you don't need it, if it doesn't, or feels unhappy, go back to decompressing.
 
Spray 1/2 a can of Start ya Bastard into the air-cleaner. (I think it was Paul Rainbow who gave us that tip on another thread: correct me if I am wrong) ?

My mistake! ☹ It wasn't Paul at all: maybe PVB?

My Perkins starts immediately but then in Australia we wouldn't get the extreme cold that you guys get.

 
My Albin petrol engine (previous boat) had a very variable response to efforts to start it.

I recall once, when the battery was flat and the hand crank dogs had worn off, tying a rope round the flywheel, attaching a bucket to the rope end and chucking it over the side when underway. It started!

it doesn't bear thinking about the danger.
 
My Albin petrol engine (previous boat) had a very variable response to efforts to start it.

I recall once, when the battery was flat and the hand crank dogs had worn off, tying a rope round the flywheel, attaching a bucket to the rope end and chucking it over the side when underway. It started!

it doesn't bear thinking about the danger.
Bit like one of the long distance racers, who led the mainsheet below, wrapped it round the flywheel and did a sudden jibe. Engine started.
 
Tranona's comment was interesting, as I'd not thought for a second about the oiling of the rings to increase compression.

Comes from my Seagull days when we started new engines. If they were slow to get away a quick squirt of oil into the carb intake usually worked. If your engine has been rebuilt with new pistons/rings then it may take some time for them to bed in. I lived with a 1GM for 20 years and it always started instantly in normal use with just wide open throttle, but if left for a time unused or in very cold weather a few turns with the decompressor lifted to get oil circulating.
 
My previous engine had the "rope start" option, as can be seen on the lower wheel, at the 7 o'CLock mark, where the indentation for jamming the rope was. It possibly would've worked had there been a decompress lever and some of the magic SYB spray.
Another bit of poor design here is that the wheel turns CCW, so trying to fabricate a starting handle onto the retaining bolt was going to be a failure, as it unwinds the bolt.
Don't bother asking me whether I found it out, or worked it out through reasoning....... :rolleyes:
Screenshot 2021-12-19 10.28.03.png
 
My mistake! ☹ It wasn't Paul at all: maybe PVB?

My Perkins starts immediately but then in Australia we wouldn't get the extreme cold that you guys get.

Certainly wasn't me Clive. I do remember the thread, where i suggested that over use of any sort of SYB/Easy Start was a recipe for a bent conrod.
 
My old RCA Dolphin was a string job. Since it only had a Dynastart this was often necessary. The string had to be wound round the centrifugal clutch which was at the rear of the engine. I think it was a couple of turns or so, and the tail was led over a groove on top of the engine and pulled in a forward direction, which mostly worked.
 
Not wishing to do a Monty Python ( four Yorkshiremen ), but the worst engine I had was an inboard seagull with a pull start .
But when it failed to start … at least it was quiet ?

Like the OP, I’ve always been a tad reluctant to just fire up a diesel without winding it over a bit to get the oil around, but not so long as to overfill the exhaust riser with seawater . ?( has to be mentioned I guess).
 
Like the OP, I’ve always been a tad reluctant to just fire up a diesel without winding it over a bit to get the oil around, but not so long as to overfill the exhaust riser with seawater . ?( has to be mentioned I guess).
Very good point, however my water pump to the exhaust is an electric item, which I activate after the engine is running, it's the same switch which activates the alternator.
 
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