Genesis 2000 side burner orifice thread size


 
K

Ken Ba

TVWBB Member
i want to reduce the size of the orifice on a genesis 2000 side burner, LP. the orfice now in the side burner is drilled for #58 drill, equating to about 12,000 BTU. i would like to de-rate it to about 6-7000 btu. i have a data sheet that gives the proper drill size for different BTU outputs.

is the orifice thread size 1/4-32 unef or M6?

thanks
 
I would guess it is 1/4-32 as the M6 denotes a metric fitting I am pretty sure. I think it unlikely that Weber would have been using metric fittings back in the 90's.
 
Bruce said:
I would guess it is 1/4-32 as the M6 denotes a metric fitting I am pretty sure. I think it unlikely that Weber would have been using metric fittings back in the 90's.
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i'm embarrassed to say that i never considered removing the orifice from my side burner and measuring the threads!!

anyway, it appears to have 3/8" threads, not 1/4" or M6. i did some further digging here and folks say the older grills had orifices with larger diameters.

now i need to find one somewhere!! the orifice diameter i'm looking for is a #68 or 69 drill hole. an undrilled one would be fine, too.
 
Not
Ken Ba said:
i want to reduce the size of the orifice on a genesis 2000 side burner, LP. the orfice now in the side burner is drilled for #58 drill, equating to about 12,000 BTU. i would like to de-rate it to about 6-7000 btu.
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Here is a sticker from a 1990 or 91 Genesis 3 showing the side burner rating is 10k BTU.

I'm not sure if later years genesis 3000s went to 12K or if they were also 10K.

20250802_105203.jpg
 
DanHoo said:
Another thread that might be useful.

https://tvwbb.com/threads/genesis-3000-side-burner-orifice.97812/
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thanks for the link to that thread. one person gives the thread size as 11/32-32. i am at our summer house, where the grill in question is, and to my eye the current orifice threads look just smaller than 3/8" so i think the 11/32" is right. i will wait till i get home and put my calipers on the threads before i buy a new orifice.

i'm now a happy camper!!
 
i ordered a spud orifice (11/32-32 threads, #70 drill hole) from the source in the thread that was referenced. ordered this morning and already shipped! i ordered 2. one i will drill with progressively larger number drills and if i overshoot i will have the second one to drill out.

the issue i'm having is i believe the orifice in the side burner i have is too large for propane, and the burner tube diameter isn't large enough to carry enough air for proper combustion. i have cleaned the burner tube best i can. the symptom is the ends of the flames are excessively yellow and lots of soot is produced. the side burner was salvaged from my old genesis II, NG, and the flame was fine--no yellow. i can't lower the flame enough to get the yellow to disappear without the burner almost flaming out. for about $11 for 2 orifices including shipping i thought it was worth a try to reduce the gas flow. i will only use this burner to saute onions and other things my wife doesn't want cooked inside our summer house!
 
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Ken, the principle behind the fuel-air mixing is that, as the gas is discharged from the orifice, it is spewed into a venturi or mixing area of the burner tube, which creates a low pressure area that draws outside air in to mix with the fuel.

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There is a shutter there that can be rotated to adjust the air inlet. The venturi area is more easily seen in the main burners, shown below.

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For some reason, adequate air is not being drawn in with the fuel that is discharged from the orifice. Assuming it was working at one time, what did you do to cause it to stop working?
 
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all i did was to relocate the side burner from my old Genesis II (NG) (which i thought was a 2000 but found the manual which said Genesis II) and installed it on my genesis 1000 (LP).

the shutter is fully open.

i feel that the orifice is for NG. i can't swear to it, but i'm fairly sure i would have bought the side burner for NG since i had converted the Gen to NG by the time i bought the side burner.

we'll see if this theory is correct when i get the new orifices which should arrive by Monday. the orifices have a #70 hole. i have a diameter to BTU conversion chart. i will start with a #67 hole which correlates to about 6700 BTU on LP, and go up from there.
 
From what I have read on this forum, people generally don't have issues with the side burner when converting from NG to LPG. Most if not all of the issues with the conversion is that the orifices and passages in the valve are not calibrated for the gas and the low- and mid-range can't be dialed down correctly, and for most users throttling the side burner doesn't appear to be a priority. The only other thing that could be checked is to ensure the orifice is aimed down the center of the mixing area in the burner tube and not cocked to one side, and that the burner is clear of any obstructions that would impede the gas-air flow. Best of luck to you, Ken!
 
thanks. i will check the alignment of the orifice to the burner tube. i have cleaned out the burner tube the best i can. it has a sharp 90 degree bend at the burner head and no tool that i have, or improvised piece of wire, can make that bend and still be effective looking for obstructions.

if my very foggy memory is correct (from 25 years ago) i very likely bought this side burner set up for NG. the #58 hole in the orifice corresponds to 6300 BTU for NG. it is not impossible that the diameter of the burner tube and the design of the venturi won't allow for twice the airflow, which would be required for the #58 hole and LP. that's why i will drill a new orifice for about 7000BTU and see what the result is.

the venturi section on this tube is not as narrow as that on the main burner tubes, which would result in less-effective venturi effect but would have been sufficient for the BTU rating that the burner was designed for.

i'll update when i have the new orfices and have drilled one to my satisfaction.
 
Is there any way that you could blow some compressed air in either or both directions down the burner tube?
 
the burner head is permanently fastened to the tube. a couple of inches from the bottom of the burner head the tube makes a sharp 90 degree bend, whcih is what is the obstacle in fully inserting any kind of cleaning tool/brush.

if i stil have a yellowish flame after i de-rate with a new orifice to 6000 btu, then i i will need to get creative in cleaning. but since the flame was fine when the burner was on NG (6700btu with the orifice that is in it) i'm expecting it will be fine on LP with a smaller orifice.
 
Ken Ba said:
thanks. i will check the alignment of the orifice to the burner tube. i have cleaned out the burner tube the best i can. it has a sharp 90 degree bend at the burner head and no tool that i have, or improvised piece of wire, can make that bend and still be effective looking for obstructions.

if my very foggy memory is correct (from 25 years ago) i very likely bought this side burner set up for NG. the #58 hole in the orifice corresponds to 6300 BTU for NG. it is not impossible that the diameter of the burner tube and the design of the venturi won't allow for twice the airflow, which would be required for the #58 hole and LP. that's why i will drill a new orifice for about 7000BTU and see what the result is.

the venturi section on this tube is not as narrow as that on the main burner tubes, which would result in less-effective venturi effect but would have been sufficient for the BTU rating that the burner was designed for.

i'll update when i have the new orfices and have drilled one to my satisfaction.
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The burner tube whether NG or LP are all the same tube and venturi. The only difference is the orifice and the gas fittings to attach. I've hooked up LP to NG side burners and vice' verse' and other than higher or lower output have never seen your issue. You have something else going on but it's not the orifice causing your problem and certainly not a "difference" in the tube or actual burner
 
You need to get yourself to Hazard Fraught or some similar store and find some long but flexible nylon bristle brushes and get that venturi tube cleaned out properly. A piece of wire ain't gonna do it
 
Take it to the car wash and blast it with the DIY hose. Then finish off with your car/truck. Any tubes that I intend to re-use get hit outside and inside with my pressure washer.
 
I agree 100% with what's been said and I'm inclined to think there could be something here that could be a teaching moment...I'm here for it! The gas flow and mixing principle is easy enough to understand, but what or where is the hitch in the git-along? My thought is that something is impeding the free-flow of the fuel-air mix and that is causing an upset in the amount of air that is being drawn in...or there is an outside chance that possibly the gas pressure isn't high enough to create enough velocity to draw in an adequate amount of air to create the proper air-fuel ratio...but it's much easier for me to see this as a flow problem.

If you were to put that burner back where it came from and it works properly, that would narrow it down to being a problem with the grill and likely a pressure problem. Personally, i would get it working as is before adding another variable to the mix by messing around with orifices. You might just end up chasing your tail with a self-created problem otherwise.

On a side note, I found my manometer that I bought about 30 years ago when I was troubleshooting the 4-burner range in the motorhome. YAY! But that's what you need to do a quick pressure test. I should take a picture before I lose it again. :)
 
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Have you tried swapping burners around? Maybe swap orifices between the affected burner and a good one?
 
Bruce said:
Take it to the car wash and blast it with the DIY hose. Then finish off with your car/truck. Any tubes that I intend to re-use get hit outside and inside with my pressure washer.
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After using a wire wheel to clean the holes, I’ve recently started to just use my garden hose with a regular spray nozzle to flush out all my used burner tubes (spray nozzle staring at the tube hole end). I couldn’t believe that they all put out perfect blue flames afterwards with just the hose flush alone.
 
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