Calibrating late 70's Magic Chef oven

[blickcd]

Just changed the gas regulator and have proper pressure, now the oven runs a little hot. Set at 350 the temp is 375.

I've tried to adjust the calibration screw in the center of the stem for the oven thermostat knob but it seems to be stuck.

Directions say hold the stem while turning the screw in the center. What is the best tool to hold it with? I am afraid of crushing it with pliers if I squeeze any tighter. Do I push in on the stem when turning the screw or not? Maybe soak it with a little solvent like PB Blaster? I want to make sure the screw turns easily before proceeding since it is small, brass, and probably easily damaged.

Christopher

[TG Twinkie]

I wouldn't mess with trying to calibrate the thing. It's off by less than 10%. If you want 350; set it a 325. I think if you use an oven thermostat you can get it to the temp you want. If you do manage to adjust it, I think you will find it will be difficult to calibrate it to where it will be accurate at a range of temps.

[blickcd]

Good point TG, but I am too stuborn to give up, and I managed to get it calibrated.

With the oven and pilots off I sprayed a tiny bit of PB Blaster on the adjustment screw and let it soak in for about five minutes. Then, with the control knob still in the Pilots Off position so that it is locked in place and making a mental note of the starting point, I used a small screw driver to get the adjustment screw freed up. It does not turn easily and that is probably a good thing.

From the original starting point I backed the adjustment screw down just a bit, then fired up the oven at 350 with a thermometer in the center of the rack. 20 minutes later it was at only 300 so I had over done it.

Trying to hold the control knob stem and turn the adjustment screw at the same time is still next to impossible. With the oven off (knob locked in place) I tweaked the adjustment up just a hair and turned the oven on again. After a short time it was at 350 and stayed there.

Later I tried the thermostat at 400 and it held at that temperature as well, so the dial is probably pretty acurate in that range now.

Christopher