still having coolling problems

[stuntman]

When I am driving the temp is fine,when I come to a stop light the temp goes way up. I replaced the fan clutch, the radiator and the thermostat. Not sure what it could be now. HELP! Its a 96 ranger 3.0 auto.2wd. It runs fine other than that.

 

[RonD]

If you replaced fan clutch then it will be a water pump issue.

Radiator issue or any clogged passages cause overheating at speed, but cools down when stopped.

Water pump impeller/fins can get eaten away if coolant is not changed every 2 years, at higher speeds/RPMs there is enough circulation but as you slow down and stop the smaller fins can't keep circulation going fast enough.
If you raise RPMs when stopped does temp start to drop a bit?

 

[adsm08]

I'm with Ron. The 3.0 had a particular issue with eating the water pump fins.

Also, when looking into an over-heating issue first you make sure the coolant isn't low. Then you replace the water pump and thermostat. Only then you do look at issues with the fan and radiator.

 

[stuntman]

Yes when I am stopped and raise the rpm,s the temp goes down.

 

[adsm08]

Do the front cover gasket while you are doing the water pump. It will be worth it to not have to worry about that later.

 

[cbxer55]

My 98 still has the original pump and radiator. Never had a problem with it overheating. Had it 17 years and put 151,000 miles on it so far. Only changed the coolant twice in those 17 years. I did put a 180 thermostat in it way back in like 2002. That really made the temp gauge needle move downwards. Despite what Ron D. may say, my temperature gauge never even gets close to the halfway point. Typically rides around the quarter mark, which it didn't do with the stupid 195 stat. Ron also says a lower temp. stat. makes your mileage worse. Mine never was that great to begin with. Yesterday filled it up and checked mileage, 18.6. That's about par-for-the-course for mine. I don't recall ever getting much higher than that, even when it only had 10,000 miles on it and was two years old.

 

[RonD]

Yes when I am stopped and raise the rpm,s the temp goes down.

Unless the new fan clutch is bad then water pump is the problem.
Fan clutch is heated by the Radiator, not the engine.
Before Cold Start open hood and try to spin the fan, should not spin, should barely move.
Start engine, hood still open, you should hear louder whooshing noise as fan clutch fluid is cold and fan is locked, after 5 to 10 seconds noise should go away as fluid warms up and fan clutch is fully unlocked
Shut off engine, try to spin fan now, should spin easily
Close hood go to work or for a drive longer than 15 minutes
Shut off engine, pop hood and try to spin fan, should be harder to spin, as rad warms up fan clutch engages more, the hotter the rad the more it engages

 

[adsm08]

My 98 still has the original pump and radiator. Never had a problem with it overheating. Had it 17 years and put 151,000 miles on it so far. Only changed the coolant twice in those 17 years. I did put a 180 thermostat in it way back in like 2002. That really made the temp gauge needle move downwards. Despite what Ron D. may say, my temperature gauge never even gets close to the halfway point. Typically rides around the quarter mark, which it didn't do with the stupid 195 stat. Ron also says a lower temp. stat. makes your mileage worse. Mine never was that great to begin with. Yesterday filled it up and checked mileage, 18.6. That's about par-for-the-course for mine. I don't recall ever getting much higher than that, even when it only had 10,000 miles on it and was two years old.

You do know that your factory temp gauge is an idiot light, right?

 

[RonD]

adsm08 ???? temp gauge is analog, oil gauge is digital, on/off like a light

MPG will improve with 195degF thermostat, just repeating what the guys at SAE(society of automotive engineers) discovered with their testing of engine temps and the best coolant temp for efficient engine operation.

Doesn't mean it is true, but probably likely that it is.

From what I have read there will likely be variable temp cooling systems, computer controlled electric pump vs fan belt driven water pump, to set cylinder temps on the fly for better MPG and lower emissions at any given load

 

[cbxer55]

Forgot to mention that the 18.6 mpg that I recently got is on 15% ethanol and driving 90% of the time with the overdrive off. I turn the od off as soon as I start the truck, same with my Lightning. I only turn the od on when on the highway at speeds over 50 mph. Otherwise it stays off all the time.

And no, I do not consider the temperature gauge to be an idiot light. Unlike the oil pressure gauge, the temperature gauge changes due to various things, including a lower temperature thermostat. It shows when the engine is cold, and slowly rises as the temperature rises. I know the oil pressure gauge is nothing more than a glorified idiot light. Not so the temperature gauge. One time, the belt broke on me, and MAN did the temperature gauge take off for the moon. Almost hit the max mark before I got it to the road side and shut it off. And that was with the heater going full bore. When the belt broke, I turned the heater on full so I could get off the road before it overheated.