Running Out of Fuel on overnight cook

[MadMedik]

Okay, you may have read the rather long post about my 8 pork butt cook. Long and short of that story is that while lighting my fire at 9pm, getting it to 250 degrees and starting my cook at 10pm my coals were completely burned out by 0800 the next morning.... I know, this is nearly sacreligious to say such a thing...the KK can burn for days at 250. I don't dispute that, but here are the before and after pictures: Before: ( i guess i should quit turning my camera...sorry for sideways pic) After cook: The coals were full up to the top ring of the fire basket. The problem as i see it was that my Royal Oak charcoal bags had very few large pieces, a small amount of medium, and tons of smalls. I would say i had about 15% large (or less), 30% mediums, and 55% smalls... LOTS of smalls. If you read my post on the cook, I used the Stoker system...had difficult time re-establishing desired Temp after putting meat on, then the fluctuation of TEMPS throughout the night was terrible....+/- 10 degrees over several hours...then the Blower blew for nearly the last 2 hours without stopping....and the heat of the KK was declining. When done with the cook, and look down inside the coal basket, I had 1 little piece of charcoal in the basket. Good thing the meat was done. I know Dennis says this should not be possible. I can tell you the temps did not get too high and burn too fast. I did not have the lid cracked open (not closed fully). the blower blew alot during this cook. Perhaps this causes the fuel to burn faster? Lots of small pieces....i think they generally burn faster than large pieces of coals?? I don't know. Any thoughts on my empty basket of coals with less than 12 hours of trying to maintain 250??? Thanks

[Tucker]

Re: Running Out of Fuel on overnight cook

I have used Cowboy, BGE, Dennis's extruded and Royal Oak.

Of the four I find the Royal Oak burns the fastest.

I experienced the same thing when using royal oak overnight, but since i had used the others for the same cooks, i convicted the Royal Oak.

Once i finish the batch i have of Royal Oak (for non-overnighters) i won't go back to it.

[bryan]

Re: Running Out of Fuel on overnight cook

Lots of small pieces....i think they generally burn faster than large pieces of coals?? I don't know.

Any thoughts on my empty basket of coals with less than 12 hours of trying to maintain 250???

Thanks

Looks like you had an outstanding cook even with a bad bag of charcoal. Congratulations on the cook.

I think you have ascertained the answer.

Small pieces equal very little heat. Blower working to get more heat burned excess coal.

By the last 2 hours volume of fuel was just not there to maintain desired heat.

[Firemonkey]

Re: Running Out of Fuel on overnight cook

I use royal oak as my everyday charcoal- even on overnight cooks. I have never run out. I don't have a stoker or guru, so I can't comment there, but I can tell you that your basket was underfilled for an overnight cook. I fill my basket up to the top of the handles for an overnight cook. Not outside of the fire ring, but I heap the charcoal on the basket until it's up to the top of the basket handles. Sometimes I even have to nestle the deflector to get it to sit level, and sometimes the deflector is actually resting on charcoal, and settles down onto the handles as the fuel burns away.

The extra lump is good insurance against what you experienced and there is no harm in having more lump than you need, as you can use it again next cook.

With extruded, I try not to load too much extra beyond what I think I will use, but with lump I load as much as I can fit for any long cook.

[mguerra]

Re: Running Out of Fuel on overnight cook

I use Royal Oak exclusively and have never had this occurrence. Maybe you had an aberrant batch. Do fill the basket all the way. It looks like you had WAY too much airflow, but you are pretty sure that's not the case. So I think just an odd batch of charcoal.

[fcnich]

Re: Running Out of Fuel on overnight cook

Ditto on that, i used Royal Oak also for an overnight cook, filled the basket to the top. I had about 25% of the lump left at the end. About a 13 hr cook.

[Tucker]

Re: Running Out of Fuel on overnight cook

I guess maybe i did get a batch or RO that was substandard, but it was a 120# batch. Not pretty.

No worries, i have what i need to get through the overnighters consistently.

[DennisLinkletter]

A charcoal's density determines burn time..

The amount of available BTUs in charcoal is directly related to weight not volume.

It's the charcoal's density that determines how long it will burn..

Just like a pine log does not burn as long as an oak log.

I assure you that you would only get an hour or two out of balsa wood charcoal..

Iron wood charcoal would burn for a week or more.

If you recall the 82 hour burn used 16 lbs of charcoal.

Carbon is carbon.. it just comes in different density and volatiles.

This is why people prefer hardwood charcoal.

It's of course more dense, has more BTUs per bag and burns longer with the same volume.

Your KK will be happy to burn it all.. All densities of carbon require the same volume of oxygen to burn at any given temp, so your results will be the same both densities.

You did notice there was very little ash.. You did not burn much carbon..

This is also why hardwood charcoal usually comes in smaller bags but has the same weight as some larger bags. I remember buying a huge bag of BGE charcoal once that weighed nothing, carried it with one hand.