This is my problem: whenever i put my truck in 4x4 and start drivin her in 1st gear through mud pits and up hill climbs she starts overheating; Or in the only other case i have of her overheating is, if i let her idle for about 15-20 mins it will start overheating. Also, my heater will only ever blow out luke warm air and then if my baby starts overheating and i let her cool down the heater just blows out cold air - not AC air but like outside air (which in my case is not warm)

Note: i just changed the thermostat last night and so i took her up to this wheelin spot to test here out. Well it seemed like it didnt overheat as fast when i put in that new thermostat but it still overheated.

If anyone has any ideas to what my problem could be please drop me a line.
So far im considering a clogged radiator hose or perhaps a busted heater core.

 

Could be a clogged radiator.... air bubble in the coolant system.... Clogged / pinched radiator hose... i would say thermostat, but you said you changed it...

Rocky

 

I also dont think its just because its in 4wd, i think its just when a harder strain is on the motor... same with letting it idle... if it only does it every once in awhile i would check on doing a full coolant flush and make sure there are no air pockets...

 

^^ i also dont think its teh 4wd,i would say look at the radiator

 

well i changed the radiator fluid and hosed it out with water. is that what you mean by doing a coolant flush? i dont know if this has anything to do with it but its worth mentioning. i noticed that my radiator fluid always turns brown like theres a lot of rust in there. Also, when you say check for air bubbles...how would i do something like that? is it just a visible thing?

 

What do you mean it always turns brown? In what amount of time? You might consider taking it somewhere and having it flushed.

 

i think it turns brown almost immediatly. in my radiator overflow its always brown and when i drained my radiator fluid to change my thermostat all of it was a dark poopy brown. i just changed my radiator fluid about a month before i just recently drained the fluid. i noticed that the cover of my thermostat - the part thats bolted on was all rusted inside. i tried scrapin the bigger chunks out. anywho could that be a sign of a problem?

 

ur fluid shouldnt be brown..lol..id take it in to aamco or something to have it looked at,or atleast somwhere where they will look at it for free.U may need a new radiator because it seems like something is getting your fluids all dirty..have it checked out

 

sounds exactly like a astro van that came in the other day... for a "coolant flush" **** was brown, and caked in the block, hoses, overflow, etc... we replaced the radiator, thermostat and hoses... and flushed it about 3 times.... and it was still coming out alittle dark...

Take it somewhere so they can hook up the machine to it, and flush it... dont put water in it at all this time of year... any water left over will freeze and possibly crack something...

Air bubbles are not visable... think of like... drinking pop and having to burp... it just wont come up... most cars come with a tiny 8mm bolt that unscrews to relieve pressure.. until coolant starts coming out... but on other cars i just leave the radiator cap off, and keep topping it off... it can get messy, seeing as when it "burps" some of it comes out...

But all in all, if i were you, i would take it to a shop that flushes.. NOT midas, lol... just ttell them you want it flushed until its the right color...

Rocky

 

i like that, "have em flush it til its the right color", hell yea. ill do that. But do you think that will fix my truck from overheating, or how about not getting any hot air in the cab? i really want to fix those things.

 

Get soem coolant flush and do it yoruself..!

its as simple as draining all the coolant (sucks and somewhat expensive to refill sadly), put in a 30 minute coolant chemical flush that will dislodge any rust buildups.. let your truck idle for 30 minutes, come back out, flush the radiator out with clean water and keep it flowing for a couple minutes to clear out all the flush chemical. Then fill her back up with your choice radiator fluid =)

 

From the color, is it oil in the coolant? Feel it between you fingers. Does it feel oily? If it does thats bad news. How many miles? Does it hold coolant constant (not leak any or get low). Oil change regularly and not get low and look normal?

 

Anytime you have poor heater performance (and no leaks) it's because of debris build up. (there is a possible valve in the hoses.. but I don't think rangers have them?)

Heater core flush:
Turn the heater setting to hot.
Disconnect the heater hoses from the engine end.
Flush them as good as possible w/a water hose until you see nothing but clear water.

Radiator flush:
Remove the lower & upper radiator hoses.
Remove the rads drain plug
Flush with a hose / sprayer until you have nothing but clear water running out. **you may have quite a bit of junk in the bottom of the rad. If so spray the nozzle up into the lower hose connection tube to blast it loose**

Engine flush:
Remove the t-stat
Flush from the top down at the stat opening & the heater hose connections.

Put everything back and fill with only water.
Drive the truck for a good 20 minutes and then re-drain the system.
Now fill with a 50/50 mix and you should be good to go.

Also, while your doing all this make sure you spray out the fins of the rad. You might have some mud/debris buildup that's not helping this situation out.

Rich (OEM cooling engineer for 6 years )

 

sounds like air, did you properly bleed the coolant system?

 

I'd buy a chemical flush, dump it in, and drive it to a shop for a machine flush. You can effectively flush a well maintained system at home, but this one sounds pretty bad!

 

my truck is about to turn over to 100k miles today a matter of fact. My truck has no leaks whatsoever. No oil in the radiator fluid. When i bought the trucka bout 7k miles ago the truck was extremly dirty from being driven on gravel roads. I farmer owned it and im thinken that it may be clogged with dirt from driven on dry gravel roads.


I have never bleeded my coolant system to my knowledge, where is the bleeder located? i have bleeded the clutch slave cylinder before and my breaks. so im a lil familiar with this.

 

There is no "bleeder" on the cooling system. The only way to "burp" the system is to have elevated rpms when the stat opens.

Rich

 

Rangers have a heater control valve. It located right next to the heater core on the hoses.

BigDank, get the coolant back to the correct color. As far as bleeding the system, just let the truck run 15-20 minutes with the rad cap off And heater on high. Maybe longer if its cold out.


While the truck runs it will puke air into the radiator. Just top it off before you put the cap back on.


Also check the reservoir tank and flush it.

 

+1 He's right. And someone said dont put any water in your coolant...DONT DO THAT! Antifreeze alone will cause your motor to overheat. Water conducts heat far better than antifreeze. The only purpose of antifreeze is to lower freezing point and raise boiling point.

 

Thanks for the catch Blhde.

And straight antifreeze is not good. It's boiling point is lower than a mix of antifreeze / water. It's just a waste unless your at the north pole.... in the middle of winter.

Most people in north america (including Canada) will be fine with a 50/50 -to- 30/70 mix. (50%-70% antifreeze) Also, antifreeze has anti corrosion ingrediants in it. So a fella ought to run at least a 30% mix of it just for that alone.

What is more effective and often gets overlooked is the rad cap or the degas bottle cap. They do go bad over time!

Rich

 

Any kind of "thumping noises" in the cab? Some 4.0Ls had issues with the water pump.

 

Only because it hasn't been suggested, I'm wondering if part of the problem could be the cooling fan. That would explain the overheating after 15-20 mins of idling, as well as the overheating while under load.

 

Maybe, but i drove in the middle of summer with no fan on 90+ degree days. I even used the AC. Never overheated at the light, or in the drive threw idling
for about 10 minutes. However the AC didn't work unless your were moving 10 mph +. Its a pretty stout cooling system.



The brown coolant is hard to overlook as a problem. Even if it means new radiator and heater core to get rid of.

 

its not the fan ur fluid is brown lessen to these guys they are right flush your system and get the crap out of it. its not a water pump or u would be loosing fluid. go get ur system flushed b4 you really damage ur motor

 

Great point!