Help w/ MM360 inconsistency

We recently opened a 2nd location and have a very old MM360 oven in there. Same one that was in there (used) when I worked at this location (different pizza shop) 20 years ago. So this oven is at least 25 years old. We have been getting a lot of inconsistencies with baking ever since we opened. First it was the timers. Both timers are between 0:45-1:00 different from the displayed time to the bake time. The prior pizza shop was cooking pizzas in like 5:00! Not possible (pan pizzas) with this oven.
Then it was the temperature. The top oven was set at 505 deg, actually read 570+ w/ a digital thermometer. The bottom was set at 515, observed 555 deg.
So we adjusted both ovens down to appx 500 deg observed temperatures and have tuned the time to that. Both ovens are cooking somewhere over 6:00 now. However it is still not right. I will get occasional burned pizzas. Sheet pizzas will cook darker on the outsides and lighter in the middle - noticeably.
And then we get to the fingers. I have not made any adjustments to the fingers yet, but the setup is nothing like our other store (same oven). Some of the top fingers in the bottom oven are even upside down and pointing up at the top oven instead of at the top of the pizzas. And the openings in the fingers do not match up to what we have in our other store.
Does anyone have any suggestions? Would replacing the thermocouples help get better temperature readings? I know that the top oven has had a lot of service in the past few years due to overheating (obviously, it was running at 575 degrees!). Will someone from Middleby come out and bring different finger covers to help us get this thing tuned in?

Reading it, my first thought was thermocouples. Certainly sounds like there are multiple issues though.

Can you post pictures of your timers and thermostats?

Here you are. Not sure how this is helpful though. The time and temp (actual) is not what these are set at.


Edit: the top picture is 435 for the set point. It wasn’t changed after baking cookies

Agreed you should check the thermocouples.

I have the same rotary timer. If I don’t have the dial “clicked” just right on every number, the conveyor speed can vary widely. Fiddle with the dials and see if your track becomes more accurate.

Also, when you time it, time it both conveyor edge to edge and oven entry to exit. You might think your timer is set to one when it is set to the other.

Since this is a new place, there could be other factors that were never a problem at your prior place. In my own case, we had a problem with the make up air blowing too close to the oven. When the temperature fluctuated outside, it wreaked all kind of havoc. It took us forever to figure out. I diverted the make up air vent and it solved a lot of problems.

Last but not least, check the tension on your conveyor. Your conveyor may be getting stuck (too tight) or skipping teeth (too loose) leading to perceived problem with the timer, but its really just the belt.

I think it’s time for new ovens

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You should also get a manual that shows the correct finger confuguration.