Microwave Magnetron

Unpluged power cord!! Removed front control panel to expose electronics (need to remove top horizontal vent cover to expose mounting hardware). Unplugged leads to control panel board. Removed magnetron with Tstat (3- phillip heads, need stubby). Installed new parts and control panel, plugged it in tested. Done.

1) Removed 4 screws securing the microwave to the cabinet.2) Slid microwave out, unplugged and placed on a work surface that allowed lower trim to hang over. 3a) Removed two screws and removed the cover on top of the oven. 3b) Unplugged high voltage plug from Magnatron. 4) Removed wires from overtemp fuse mounted to Magnatron. 5) Removed the four screws securing the Magnatron to the oven. 6) Removed Manatron. It's a tight fit, but can be done without removing anything else. 7) Replaced Magnatron. This is where I needed the magnetic part retrieval tool. The nature of a Magnatron is the use of strong magnets surrounding the tube. Getting the four screws back into place wasn't possible with just a normal magnetic screwdriver tip. I used the retrieval tool to position the screws back in place. Be sure to not initially tighten any screw completely, until they can be evenly tightened. This ensures correct compression/seating of the shielding material near the neck of the tube. 8) Reverse removal steps. Plugged in and tested microwave function on a cup of tap water. 9) Reinstated in cabinet and got a big thank you kiss from the wife!

Symptom: Terrible sparking coming from the right side of the microwave even with nothing in the microwave. The part that was behind the cover was the business end of what I learned was the magnetron,

Repair process: Without appliance repair experience I went onto Google and searched for parts for my model PEB1590DM2WW. I was able to find a great parts schematic on partselect.com. At first I ordered a magnetron and while waiting for the parts to arrive I also learned that the capacitor can also fail easily as described in the other install feedback on the partsselect website. So I ordered a capacitor just in case. These convection microwaves are around $600 new so a $80 in parts is not out of line for 8 years of service.
I installed the magnetron first and turned it on. sparking immediately continued so I quickly shut the unit off. After replacing the capacitor and letting it charge for several minutes before trying to start the microwave cycle was the issue. I choose to leave the replaced magnetron as the original unit was discolored and felt the replacement was inexpensive insurance. I also learned that if the wave guide (which is a plastic/metallic composite material) that covers the opening to the magnetron is burnt or has metal melted to it as mine did it will act similar to the microwave having metal inside the enclosure and will continue to spark and basically melt the wave guide further. Replacing the wave guide was very easy as well.

I am very thankful for the knowledge base and support available from Partselect.com as they made this repair possible on my own. Thank you partselect.com

Microwave with no heat. Removed casing and checked low voltage side from the fuse through all the microswitches to the primary side of the transformer, all good. Checked HV diode good. Checked secondary side of transformer, good. Checked capacitor, good. Even though the Magnatron electrically checked out good, it had a cracked magnet. Replaced the magnatron and we have heat again!

I removed the main cover ( torx security bit required) and tested the magnetron, capacitor, diode and door interlock switches according to instructions found on the internet. The capacitor and diode tested good but the magnetron looked burnt and corroded on the tip. The magnetron I received was an exact replacement for the original. It was easy to replace the magnetron which arrived in 2 days standard shipping. I also cleaned the fan while I had access to the inside area. Hoping to get another 18 years use from the microwave!

Removed cover
Disconnected capacitor from old magnetron
Removed old magnetron
Installed new part
Connected capacitor
Reinstalled cover