Kenmore Elite Gas Cooktop Orifices

[redgreen]

I purchased the gas cooktop that was very slightly used and converted to LP gas.  I want to replace the 4 orifice spuds and convert back to natural gas.  Three of the spuds are readily available and affordable but the largest burner spud (16K) is now only available as a ignitor/orifice assembly that is a lot more expensive.  Is there a good reason why the manufacturer made this change?  Is there an NG spud of approximately the same BTU rating that I could safely use?  As a last resort, who is skilled in drilling out an orifice to the proper dimension?  Thanks!

Model 790.33223400

[jumptrout51]

You can save money and drill them all out.
The brass is very soft and can be hand drilled.

[redgreen]

Drilling the spuds is an option but I'd perfer to leave it to  someone with more skill and tools. 
Also, I don't know the proper drill size for each of the spuds either.  Does someone know what drill sizes to use - especially for the largest spud (16K)?

Thanks for responding.

[JWWebster]

You want to make the hole larger for nat gas. You measure the hole using a set of standard orifice drill bits. You go 10 orifice drill bit physical sizes larger for natural gas.

[redgreen]

Is an orifice drill bit the same as a numbered bit?

Are most orifice spuds similar in physical size and threads with the main difference being the actual size of the hole? 

I'm thinking it would be easier to find an orifice with a similar BTU rating (hole size) and install it.  But, that assumes the threads are the same. 

I still wonder why I have to buy an assembly instead of just the spud.  Its only for the biggest burner and not all of them.  It seems odd, like there was a design flaw that they're trying to fix.

[JWWebster]

An orifice drill bit set is a stand alone set that is used to accurately set BTU rates per size. It cost $150 or more for a set of bits. Most peeps cannot afford it so they go to the gas supply parts warehouse and have them sized there. I used to charge $5 per orifice to resize them. Take you old one off and carry it down to the gas supplier's part room. They usually have some.

[redgreen]

Good advice.  The hard part was figuring out who to talk to.  Drilling out the orifices was very easy.  He just looked on a table of BTU values and picked the right size bit to match that BTU.  Then he picked a larger bit to chamfer the opening so that it would not whistle.  It worked great.  Its a shame that appliance technician aren't willing to perform a simple drilling job.

[JWWebster]

Glad you could get it done! The ave Tech ain't gonna have a set of those bits unless he is a gas appliance specialist and that is a rare breed.