What is the normal Operating Temp of a 1999 Cherokee 4.0 6 cyl engine. I cannot find this anywhere, does anyone know?

I replaced the Head gasket, water pump (remember all the 99 are reverse, thermostat and we were running at between 210 and 225.

I changed the fan clutch and did a complete flush and we are now at between 200 and 210 (with the ac on 88 degrees outside).

Is this normal? Is it OK to be riding on the hwy at 75mph, ac on and the temp at 210?

 

210 is normal on these. My 2000 Classic runs at a consistant 210, and our then new '99 Sport ran the same.

 

At what point should I be concerned?

 

when it gets close to the red.

 

sounds like normal to me both of mine run at 210 highway 220 city I think your fine.

 

Modern engines run hotter for better emissions.

If your 1999 engine never reaches operating temp, the PCM will never complete it's readiness tests or self-adaptation. People install 180-degree thermostats because they think that's better, and the fuel mileage suffers and the Jeep will never pass emissions.

 

Thanks for the info, I really appreciate it. I needed a sanity check, 210 seems a little high to me.

 

Mine runs 210 city or highway....

 

my '99 runs 210 all the time. summer winter doesn't matter. always has. your fine.

 

210 across the board for my 2000 also. except low range wheeling it likes to get warm. but not bad at all.

 

When it starts blowing steam from under the hood.

 

Im glad im not the only one freaking out about the high operating temperature, haha. Both of my mustangs never even see 200F

 

The target coolant temp for the 4.0 is 200-210 farenheit.

Varies a bit between vehicles.

And there can also be a bit of inaccuracy between the sending unit and the gauge. When in doubt, verify it with an infrared point and shoot thermometer pointed directly at the thermostat housing.

 

Ok, Jeep noobie here. I guess I can to learn to live with that high
temp, but is it normal to jump to 210 just after a few minutes of
running?

I got a 2000 Cherokee last Saturday. Worried about the high
temp.

Thanks...

 

Not only is getting to 210 normal, it actually is desired and the way the engine is designed to operate. The faster you get up to temp, the faster your engine becomes more efficient, both from a fuel and an emissions standpoint.

If you are 200-210, you are fine. But be darn sure that all of your cooling system components are up to snuff. You have a 2000, which from the factory, came with the "infamous" 0331 cylinder head. This head has a casting defect between cylinders 3-4, which make it susceptible to cracking in that area. An overheat virtually guarantees a cracked 0331 head.

Fresh 50-50 coolant, radiator, radiator cap, water pump, serpentine belt, hoses, fan clutch. There is no better money spent than on cooling system maintenance.