Mixer Pin Question

[Todd W. White]

You need the Service Manual. If your pin point has a hole in it, it is the Universal Mixer Pin, and you don't need to drill any holes in the Orifice Cap.

The [b][i]C-series Service Manual, Revised Edition, [/b][/i] has a whole new section in it of previously not-published-by-Chambers information on mixer pins and orifice caps.

Let me know if you need one - they're in stock.

[jsrose]

OK, here're a couple of pictures of one of my mixer pins from my 1951 61/90C (the tag says 61C, but it has a 90C high back).

[img]http://static.flickr.com/92/227861719_a9529b97f0.jpg?v=0[/img] [img]http://static.flickr.com/90/227861716_9f1b9942e6.jpg?v=0[/img]

It has the longer orifice cap (I think) like it would if if were set up for propane, but it's not screwed down tight against the shoulder like the manual says it should be for propane. And all of caps are about 5 threads out on all the mixer pins on the stove.

It has no point, it's just hollow, when you remove the orifice cap.

And the stove came from a 40s vintage house that's in a neighborhood that's had natural gas for probably that long.

So what gives? Was it set up for gas or propane or what?

And can I just screw the cap down tight to properly set it up for propane?

Also, has anyone come up with any handy household items that might be used to judge the size of the hole in the orifice?

The shank end of my smallest drill bit, 1/16", is just slightly larger than the hole if that helps. If this is the wrong orifice cap, can some of the commercial vintage stove folks supply the proper one?

Sorry for all the questions but thanks for all your answers,

Jack

[Todd W. White]

Sam is right - is is confusing (he was a GREAT help on the manual) - and if you drill the WRONG sized hole (it will ALWAYS be too big - I've never in my life drilled the wrong sized whole and it be too SMALL [img]wink.gif[/img] ), you're stuck looking for replacement orifice caps. Expensive!

[jsrose]

Hey guys, thanks, but I've got the C-series Service Manual, Revised Edition unless it's been re-revised since I bought it from Todd about a month ago (sorry Sam, but to be fair, I did buy my B manual from you about 2 months ago, and I'll probably be sending my t-stat to you, too).

So, I figure that according to the manual, I don't have a universal mixer pin, since when I remove the orifice cap, it's just hollow on the inside, no point.

But my understanding from the manual was that if there's no point under the cap, the stove must have been set up for propane. Was that a mis-understanding?

And since my mixer pin orifice is just slightly smaller than 1/16", which Sam says is between 52 & 53, and the natural gas size is 54, I must have the natural gas sized orifice. Right? Because the propane size would be considerably smaller than 1/16"?

So, are propane orifice caps available from the commercial vintage stove guys? Or from regular old, every day stove guys? Or from you guys?

Thanks,

Jack

[stoveman]

Hi Jack,
The Service manual is telling the truth about ranges as they left the factory. No one can guess what has been changed or modified by a service person in the last 50-60 years. It seems that your range has had the pins removed and natural gas orifice caps installed by a previous service person.
Now, for your stove to work on propane, you will need orifice caps that are drilled for propane. The caps that are available at appliance parts dealers are available in only 2 sizes. #56 and #72. So, new caps in your sizes are not available.
Now, there are several work arounds.
1. Buy a set of new caps in #72 size and drill them out to the size you need.
2. Find an old stove man that has some old stock or used caps.
3. Contact your propane supplier for help. They convert a lot of appliances and may have some caps. Also, they usually have a set of Number Drills and can drill different size holes. They can not drill a smaller hole.
4. Here is what I have done on strange sizes. Remove the caps and solder the too big hole shut. Get the correct size Number Drill and drill out the solder to the correct size for propane.

[jsrose]

Hey Sam, thanks, that's just what I was looking for.

Solder, huh? I had wondered about trying that with plumber's epoxy, hadn't considered solder, though.

I'll check out your leads around Knoxville. If I can't find exactly what I need, maybe I can at least find the #72 size orifice and drill it out. I do have a drill press, but I'll have to find some of those tiny number bits.

Thanks again,

Jack

[stoveman]

Hello Jack, The Universal mixer pin on the Model C will have 3 parts. The Body, the Point and the Cap. If you do not have the 3 parts, you do not have a Universal Mixer Pin. The Point is pressed tightly into the Body and is hard to remove. From your discription, you have the "plain" Mixer Pin that does not have a Point inside of it. In your case, you will need to select the correct sized Cap for your type of Gas. From the chart in the service manual, you need a Cap with a #68 drill hole in it for Propane on the Top Burners and Well. This cap should be "long", but a short one will work in your case. A #68 drill hole is slightly smaller than 1/32".

A 1/16" drill size is between #53 and #52. The higher the drill size number, the smaller the hole.

This Mixer Pin topic is probably the hardest to understand and the hardest to explain. Todd and I worked on this part of his new service manual and it is better than the original service manual. It is a tough subject to understand without a strong understanding of gas BTU's and pressures.