coolant issues

[Stkid93]

im new to the fist and wondering, what causes the coolant issues and are there any ways to help preven this? does this issue mainly affect fists that are tracking and overheated, or does it happen to all fists?

 

[gtx3076]

Some people have this issue under normal driving conditions. I never have, but being a 2014 I have a hunch that the original owner had it fixed with a cooler thermostat because my idle temps will sit at 150-170* on a cool day. My cruising temps in the middle of summer are usually around 190*. I have never had an overheating issue even sitting in traffic in summer.

 

[SteveS]

The coolant issues was mainly the early cars (2014-2015). Ford recalled them and applied a fix, and later cars had revisions which took care of that problem.

There are a lot of enthusiasts here and elsewhere who believe the cooling system is bad, and you'll always see them posting that the radiator HAS to be replaced and thermostats messed with, etc. It is certainly true that Ford did not design a lot of excess cooling capacity into the system. And that it doesn't get as hot in the UK where the car was designed and has its greatest popularity. But it's equally true that I and others like gtx3076 have never had overheating problems despite daily driving in hot conditions. I believe where the overheating comes in is when you modify the car to make more power. Accessports are very popular and therefore tuning to make power. And it's easy to do. But when you make more power, you make more heat. Along with that there is also constant chatter about needing colder heat range spark plugs. If you need those it means you are experiencing greater heat in the cylinder than normal. So if you are making more heat because of what you are doing to the engine, you may need more cooling to get rid of that heat. A radiator with better cooling capacity seems to be just the ticket for that. Another cause can also be driving the car in a lower gear than you need. This leads to running higher revs, and more heat at lower speeds, which results in less ariflow and cooling. The Fiesta ST's engine doesn't need to be revved to the moon to go quickly. Ford designed the engine the way they always have done engines for the Fiesta (going back to 1978). Lots of torque early, not a particularly high redline, and reaching peak power early. So driving it the way it was designed also produces less heat.

 

[M-Sport fan]

^^^Besides the way they set up the factory turbo sizing/boost parameters, it is also an under-square bore and stroke engine, meaning; it should NOT be screamed to high unholy hell in order to make power, as the piston speeds then become self-destructive, no matter how strong the; block, closed deck or not.

 

[Stkid93]

So a different thermostat and radiator will help though correct? What thermostat is suggested to put on?

i have an aftermarket intercooler and I run the car on e30 to help keep cylinder temps down.

 

[M-Sport fan]

In the Nutmeg State/anywhere in New England (or upper Midwest, etc.), I personally would NOT go lower than the Motorcraft 180*F opening temp 'stat, if it is a year 'round, driven right through the winter car.

Summer/track only ride I might chance the Mishimoto 160* piece.

 

[gtx3076]

So a different thermostat and radiator will help though correct? What thermostat is suggested to put on?

i have an aftermarket intercooler and I run the car on e30 to help keep cylinder temps down.

Ford makes a cooler thermostat.