How to improve airflow on Jumbuck kettle BBQ?

[Sarah_b94]

Today was my first grill on the Jumbuck Black Phoenix Charcoal BBQ. I struggled to crack 125-150 degrees with lid on or off, which made for a very slow cook. All the vents were open and the charcoal was red hot and ashed when it went in the baskets. Any tips for improving the airflow in this BBQ to crank up the temp for a sear/direct grill? 

[JacobZ]

Hi @Sarah_b94,

A warm welcome to the Bunnings Workshop community, it's brilliant to have you with us.

Generally speaking, you've done everything right. Keeping the vents open to allow airflow and ensuring the charcoal is well-lit before placing it in the baskets are the main things. 

Did you use a charcoal chimney such as this Jumbuck 3.7L BBQ Charcoal Starter when lighting your charcoal? 

On the Jumbuck 57cm Black Phoenix Charcoal Kettle BBQ there are two vents on the ashtray at the bottom, were these open? 

At the base of the kettle directly above the ashtray there is a charcoal filter to prevent larger materials from falling into the ashtray. Is it possible this was covered or blocked?
 

If closed or blocked you won't get an updraft through the coals, so they wouldn't be able to get as hot as possible. This could be the reason you struggled to get the heat up.

Allow me to tag @MoonshineBen, @MartyH and @Kermit to see if they have any ideas why you may have struggled or know any techniques to help maximise temperatures in your kettle BBQ.

You might also like to check out How To Use A Kettle Smoker for some further guidance.

Let me know if you have any further questions.

Jacob

[MoonshineBen]

Hi @Sarah_b94 - how much charcoal were you using?

[Sarah_b94]

I did about 3/4 of a chimney (briquettes) for my first grill and about the same with lump coal the second time. Way better/hotter using lump.

[Sarah_b94]

Yes, i used this brand of chimney with 2 natural fire starters (so coals were ready to go). All vents were fully open the whole first cook and i couldn’t crack above 150.

[Rolando]

I have/had what I call “performance issues” 😜. Never able to get enough airflow with all vents open, charcoal or briquettes same story: lid on and they just starve of air and go out.

I think I found some workaround, I replaced the flat grid that sits at the bottom (clogging with debris and ash all the time), with a big colander where, after removing handles, I’ve drilled lots of holes on the vertical side. Also I remove the ash collector so there’s a full 10 cm diameter ingress hole for air. 
Yesterday I cooked 2 butterfly chickens and sausages, far better performance than before, but still had to leave the lid air flow control fully open.

 

[JacobZ]

Hi @Rolando,

I am similarly not a master with a kettle BBQ and have honestly had more partial failures than roaring successes, but I love cooking, and I find the process of cooking with charcoal very satisfying. I am much better with a camp oven and open fire, but things like stews and damper are pretty hard to stuff up.

The colander is an interesting idea. Did you find the ash naturally fell away from it or did you still need to do some minor cleanup during the cook to keep the ash from blocking the airflow?

I'm glad to hear your sausages and chickens turned out better than past attempts. I am sure you'll get more use out of this over the Christmas and New Year period to really refine your technique.

Thank you for sharing.

Jacob

[Rolando]

Hi JacobZ.

The ash & embers do fall but they either sit on top of the colander and block some of the tiny passages (quite irrelevant to air flow), or roll on the bottom bell of the BBQ and come to rest against the quasi-vertical side of the colander. I have now 2 rows of 5 mm diameter holes, about 1” from bottom, plenty of room for ash to accumulate without blockages.

I’m a clean fanatic I suppose, I clean the BBQ every time after a cooking session.

Tonight we have another go, but I’ll use briquettes i just bought … in Bunnings of course. I won’t use the 2 provided half trays with holes, I’ll just pour the beads from the fire starter cylinder to the side on top of the lower grid/shelf.

Ciao