Can we run the fiesta 1.6 engine without a thermostat?

The serpentine belt has no bearing on the camshaft timing, so my guess is that you mistimed the camshaft timing for no reason.

The serpentine belt is external and is driven by the crankshaft and runs the alternator, the A/C, Steering Pump and water pump.

If your CAMSHAFT belt broke, the Ford Fiesta has an interference engine, so you have bent valves and damaged pistons.

Does A Ford Fiesta Have A Timing Belt Or Timing Chain?

https://www.autopadre.com > belt-or-chain > ford-fiesta

Ford Fiesta - Timing Belt Or Chain - All 2011 Ford Fiesta engines have a timing belt and are interference. Engine Type, Timing Belt Or Chain ..

Yes, you can. You can run any vehicle without a thermostat as a short-term measure only.

Removal of the thermostat means that the engine coolant circulates through the radiator and cylinders nearest to the radiator ... those cylinders furthest away from the radiator will consequently run hotter..

Running a car without a thermostat is a short term, get you home measure. Manufacturers fit a thermostat for a good reason. Running a car without one for a prolonged period is going to cause problems

It is not the best but can be done.
Don't remove the whole thermostat only the center part and fit the frame back in the housing.
If you remove the whole thermostat you can end up with cavitation problems and this can cause hot spots in the engine.

Fuse box is located in the glove compartment. Empty the glove compartment, then the side will pop out for access to the fuses.

Running an engine without a thermostat will allow it to run too cold. This will cause oil problems and fuel efficiency problems. The computer will make adjustments for a cold engine which will affect idle speed, timing, and pollution controls. You may have a plugged radiator or a water pump not moving enough water or a bad thermostat. The cost of a thermostat is much less than the damage you will cause running without one. If the radiator is plugged. running without a thermostat will not solve the over heating condition.

Seems that when going thru puddles the engine sucked water causing engine damage

You most likely have a defective engine temperatur3e control thermostat.

Sounds like the thermostat is failing.

Thermostats fail in 2 ways: (a) sticking open (b) stick closed

Your seems to be sticking open - and so the engine warms up VERY slowly,
but still throws a little heat out the vents - less heat over time so that
your daughter didn't even notice the gradual decrease over time.

If you can replace the thermostat on your own, your cost may be less than $5.
To get a new thermostat (always buy parts on your own - the garage will charge a
50% surcharge on any parts they have to locate for your car), try Wal-mart first
(they sell a few thermostats for a few cars), then any auto parts place.

Replacing a thermostat in a 1998 Fiesta ZTEC engine should be the first thing
a DIY mechanic learns after figuring out how to do regular maintenance items - since
stuff like distributor cap/ distributor rotor/ thermostat are actually regular maintanance
items - destined to have a limited life span, like any moving part.

yes, as long as the car is not running, it will be fine to take the thermostat out. just remember which way the thermostat came out so you will put the new one in properly, otherwise it can make your engine overheat.

Purchase new thermostat. Follow the top radiator hose to the engine and remove the bolts that secure the housing at the engine end of that hose, to the engine. Pay careful attention to the way that the old thermostat fits, pop it out and put the new one in the same way.