My Tappan overstove microwave will run approx 4 min. and then shutdown completely, display even goes blank, after approx. 15 - 20 min. it will reset it self and work again but only for about 4 or 5 min.

Bad control board.

Hello, Sarkis -

I found 4 descriptions of what may be causing the noise when you operate your microwave oven. See the information on all 4 possible causes here:
https://www.repairclinic.com/RepairHelp/How-To-Fix-A-Microwave/78-88--/Tappan-Microwave-is-loud-or-noisy

Note: Safety advice I have read regarding microwave oven repair is to have a microwave oven repaired only by an authorized repair technician. It is not do-it-yourself work.

Any repair might not be worth the cost compared to purchasing a new replacement. A microwave repair technician authorized to work on Tappan microwave ovens will be able to evaluate what is causing the loud noise and give you an estimate of the repair costs.

Note: If you find you need to replace your microwave oven, please be sure the old microwave oven is sent to electronics recycling.

Best wishes.

You didn't mention your brand or model number, but it sounds like it may be a noisy magnetron.

See this FixYa solution. even if your model number is different.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Time to replace it, the control board is going bad and that will lead to many different problems.

See this FixYa solution. even if your model number is different.

If this does not describe your problem, reply with your full model; number from the tag on or in the unit and a detailed explanation of the trouble you're having.

You have a faulty display module due to one or more components leaking. Some models have a seperate display module that can replaced without the complete board having to be replaced. If not, the board needs to be replaced. You need to ask your spares suppliers that have info. on that model.

Return it for warranty repair or replacement. Does the blower motor operate?

I think the membrane/button for the number 4 is stuck or broken. Due to the nature of a microwave my advice would be to entrust the work to a competant technician. Hope this helps.

I bought a display model from lowes tappan over the range microwave oven, and do not have the mounting plate, How can I get one?

May be a little late, but... 1. Press Power Level button for approx 5 seconds - you get the 12 hour clock 2. Press again for 24 hour clock 3. Set hours using the 10 min and 1 min buttons 4. Press Power level button 5. Set minutes using the 10 min and 1 min buttons 6. Press Power level button And you are done
Gert