Yanmar 3GM30F cold start procedure
- Thread starter Andreas T
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Wow
It must be still pretty cold up by you I guess,I don't do much cold starting much any more but when up in NY I would put the throttle half way and than start.
If it's really cold some sort of heat like maybe a heat lamp in the engine compartment would be a good idea.
Nick
It must be still pretty cold up by you I guess,I don't do much cold starting much any more but when up in NY I would put the throttle half way and than start.
If it's really cold some sort of heat like maybe a heat lamp in the engine compartment would be a good idea.
Nick
I have the 3JH3E. When it gets cold here, rare although it does happen, I have a glow plug position on the ignition key switch. It is spring loaded, so I just turn the key to the full on position and hold it there about 15 to 20 seconds, release and hit the starter button. It always fires and I roll the throttle up to about 1400 in neutral until engine comes up to operating temp. Never had a problem with it, and have used this technique in the mid 20's.
Throttle positon when starting...
on my 3GM30F I usually set my throttle to about 1/4 to 1/3 and flip two of the three decompression levers to lessen the load on the starter. Once the engine turns over and one cylinder fires, the levers reset themselves and the engine spins up.
In cold environments I've read that some use a hand-held hair dryer aimed at the air intake horn as these engines don't have glow plugs to heat things up to make cold weather starting easier.
on my 3GM30F I usually set my throttle to about 1/4 to 1/3 and flip two of the three decompression levers to lessen the load on the starter. Once the engine turns over and one cylinder fires, the levers reset themselves and the engine spins up.
In cold environments I've read that some use a hand-held hair dryer aimed at the air intake horn as these engines don't have glow plugs to heat things up to make cold weather starting easier.
A gentler method...
On my 18 2GMF I use a hairdryer with a PVC elbow to warm up through the air horn for ten minutes. Then I start with the throttle slightly open, not fully. Works wonderfuly.
By the way, if you haven't operated the engine within 48 hours and it's cold, Yanmar suggests holding the kill throttle out and "start" for ten seconds, twice. This coats the cylinders with oil more favorably.
On my 18 2GMF I use a hairdryer with a PVC elbow to warm up through the air horn for ten minutes. Then I start with the throttle slightly open, not fully. Works wonderfuly.
By the way, if you haven't operated the engine within 48 hours and it's cold, Yanmar suggests holding the kill throttle out and "start" for ten seconds, twice. This coats the cylinders with oil more favorably.
As we know diesel engines need heat in the cylinders to ignite/start. Turning the engine over for about 10-15 seconds puts heat into the engine. Let the engine soak in the heat by waiting some seconds before turning it over again. Heat is what a cold engine needs to start. By setting the throttle to a faster position the engine's compression is set higher creating more pressure and heat. As engines get older compression is lowered, which means getting heat into the cylinder for ignition may take longer. Try different throttle positions for your engine. Engines are all different due to their age and condition.
Paul: Someone explained that increasing the throttle advances the timing. I doubt that it increases the compression.
According to the service manual's cold start procedure "When the control lever is set to the HIGH SPEED position, injection timing is automatically delayed to facilitate starting." This allows the air/fuel mixture to become more compressed and create more heat before ignition. Not an engineer here, just thinking it through.
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Throttle position
I have a 3GM, and when it is warm in the summer it cranks right up, with the throttle at idle position. As temps cool off, takes more throttle. When the temp is around 50 or so, it starts best with full throttle for a few revolutions, then pull back towards idle. Usually fires right off, when the throttle is about 1/4. If the temp gets into the 30's, or lower, it can be a bear, and requires lots of full throttle. Fortunately,don't get much 30 degree weather here.
I have a 3GM, and when it is warm in the summer it cranks right up, with the throttle at idle position. As temps cool off, takes more throttle. When the temp is around 50 or so, it starts best with full throttle for a few revolutions, then pull back towards idle. Usually fires right off, when the throttle is about 1/4. If the temp gets into the 30's, or lower, it can be a bear, and requires lots of full throttle. Fortunately,don't get much 30 degree weather here.
Hmmm.... First of all, "air-fuel mixture" is a gas-engine term: in a diesel, the AIR is compressed, then diesel is injected, supposedly almost instantaneously vapourized, and burns. Now, in a starting engine I'm guessing the problem is the fuel isn't vapourizing before burning, creating the blue or black smoke. (Anyone who's started a Dickenson diesel stove would know what I mean!). Now, assuming the injection normally starts before TDC, delaying it would mean it would be injected closer to TDC so the air would be more compressed before the fuel enters, which I guess would mean it's more likely to be vapourized before it starts burning.
But unlike a gas engine, the throttle setting on a diesel does not vary the amount of air in the cylinder, so therefore does not affect how much compression there is.
druid - amused that we still call it a "throttle"
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