cold start warm up time to full load (and cool down?)

[mike90045]

  So, the clouds have moved in again, and we're getting some rain and snow.   I've got some 10-40wt in the crankcase
and wonder what the warm up idle, and load ramp up times should be for an engine (metro 6/1)  starting at 30F.

 I'm currently letting the 90 sec inverter qualification time do initial warm, then it engages about 500w of load. I've been letting that run for about 3 more minutes, and ramp up the load to 1,000 watts, for another couple minutes, and so on, till I hit 2,500 watts load at about 10 minutes.   And every now and then, I cycle the load back down to 500w, and back up to 2500w.

  Cool down, with an st5 head, I've just been cutting load back to 500w for about a minute to cool the windings down, and then shutting off.  I don't hear any gurgles from the coolant in the head after shutdown.

Should I be doing anything different ?

[Tom]

I guess I'm a 3rd world neanderthal. I just hit it with a full 3kw load after a 2 min warmup. The Outback inverters slowly ramp up the load and it blows some grey smoke for a bit until it's fully warm. My startups are usually in the 40F range, but I've done it at 30 with no issue.

I don't know if this correct or not, but I go by the color of the exhaust to know if I'm over doing it. In fact when first commissioned and before the max generator current was dialed into the inverters it ran at double plus full load for a bit. Huge black smoke clouds were billowing out of the exhaust.

Glad to hear your getting some run time on her. Are the leak issues on the head resolved?

[mike90045]

The XW inverter, after the 90 sec inverter qualify cycle, loads the engine up in about 5 seconds.  At least it's not hitting it in 1 second......

So far, the head gasket is holding, and the head temps are up there, the thermostat seems to be doing it's job, it's about 10 minutes before it starts to flow.  And I got the used radiator from the wife's car, and will plumb that in, instead of 15 gallons of antifreeze in the tank.  Then it should hit full temp in 15 minutes instead of ice water into the lower jacket for 90 minutes.

[Hugh Conway]

Our machine sits in an outside covered area. If it's really cold, that usually means the sun is shining here in North Pacific coast, solar panels kick in so no need for the 6/1. However, mostly is is overcast, and frequently hovering just below of above 0 Celsius. We need to charge batteries then.
Immediately after coming up to speed on starting, I add about 1200W load for 10 minutes, that's when the 'stat opens up. by that time, we have ensured no strange sounds, oiled things, filled in the log book, etc. After that, go to full load of about 2800W on the inverter/charger. Been doing that for quite some time, the engine seems happy to oblige. By the time we shut down after about 2 hours, the charger has reduced the load considerably, usually only 600W, so the gen head has slowly cooled. Probably a very forgiving engine in any case........it is not exactly a highly stressed piece of machinery.
Cheers,
Hugh

[ronmar]

I give mine a little more warmup time than that when it is that cold.  Till I feel warmth on the side of the head above the handcrank/start flywheel...  Then I bring on the load...  Diesels are happiest when warm.  If you are starting this manually(not automated), have you contemplated a small preheater of some form to put some heat into the coolant?  I have been brainstorming such a heater/heat exchanger that would thermosiphon backwards thru the head and cylinder with a small alcohol or propane flame to warm the coolant in the head/cylinder so it basically starts at the temp I usually place a load on...  It would require the addition of a valve in the system to keep the heat from thermosiphoning up away from the engine instead of circulating thru it...

[mike90045]

......If you are starting this manually(not automated), have you contemplated a small preheater of some form to put some heat into the coolant?  I have been brainstorming such a heater/heat exchanger that would thermosiphon backwards thru the head and cylinder with a small alcohol or propane flame to warm the coolant.......

Manual starting, and being off-grid, preheat overnight, is not an option. When the wife wants the blow dryer and doesn't want to wait for a sunny day, it's listeroid hour.  Or if I ran the heat tape on the waterlines at night, it's lister time when I get up.

  Mike

[ronmar]

I am not talking about maintaining temp in the engine, just something you go out and pour a measured quantity of alcohol into and light.  Come back 5-10 minutes later and it has burnt out, but the head and cylinder is warm to the touch.  You close a valve and crank the engine over ready to apply load almost immediately...

[millman56]

Mine just gets started up then as much load put on it as it will stand without slowing it down too much,     I just want to get it up to a temp with enough power to boil a 2 KW kettle as quickly as possible and make a brew, while drinking it I pause to consider the long term effects cold loading may have upon my engine .

Mark.           


     

[LowGear]

Hi Mark,

Who would have guessed you were so sensitive?

Casey

I set on my mower for nearly a minute before launch.  I too consider the long term consequences of this moment of calm and peace.  I've come to realize I'm a good person and love my mower.  Therapy is good!

[millman56]

Casey,     its dangerous to make assumptions about ones sensitivities, often when I`m having an hour off from my  hillbilly life,  I sit by an engine and strum Duelling banjos on my ukelele whilst  reading  Wordsworths prose.

Mark.

[Hugh Conway]

I love it here!
W.B. Yeats
“God guard me from those thoughts men think
In the mind alone.”
Cheers,
Hugh

[LowGear]

I sit by an engine and strum Duelling banjos on my ukelele whilst  reading  Wordsworths prose.

'MERICA,  It just don't get better than this!  Nowhere!

Two of my favorite parents were hill folk.

Aloha

[millman56]

Casey,   I must confess to being only a semi hillbilly,  living at only 300`elevation and working at 950`, have only 5 non webbed toes on each foot,  can only play the first 2 bars from the Hawaii 5-0 theme tune on a 3 string banjo and when I tried to use a goat as a lawnmower it ran off 

Mark.

[listerdiesel]

Not quite the same situation:

We start the Ruston under load sometimes, it doesn't hurt it as we go round oiling it up before starting, it has ring oilers for the main bearings and positive lubrication for the big end and cylinder.

I try to get it up to temperature as quickly as possible, diesels don't like running cold.







In winter it takes about 5 minutes to get up to 80 Dec C, that's with 1kW of lighting load, adding another kilowatt decreases the time by about 25%, that block takes a lot of heat.

Peter
 

[mike90045]

Decompressor & exhaust valve overheating ?

I've noticed the cap on the end of the valve stem (where the rocker arm meets it) has all the quality Indian paint burned off.

What I don't know, if this happened while running, or afterwards, with the valve off it's seat from the decompressor.  Does the valve need to sit on it's seat to cool, or does anyone else observe the same toasting of the paint ?