Hi,
As I run my 96 ranger for more than 5 Mins, The release valve on the radiator cap lets out fluid and the Collant resevoir fills up, and the temperate guage shows very hot. I also noticed that the top radiator hose that goes to the thermostat Effectively collapases like a vacume is being created (No water running through the hose). Seems Like the thermostat is stuck closed. Does this sound like the problem?
Thanks

 

theremostats are designed to stick open, not closed.....

i think it is a bad water pump......

first thing i would do is replace the t-stat, and if that doesn't fix the problem (which i don't think it will) then it is your water pump.....

 

I've had a few thermostats get stuck closed with similar results. Check that first.

 

Sounds like a bad Thermo to me....My porsche did the almost the same thing.

 

I have a 96 ranger extended cab 3.0 while I drive the temperature continues to climb until it runs hot I have installed a new water pump twice and new thermostat twice new hoses and radiator the factory clutch fan was removed and a electric fan was installed with a fan shroud. It only started doing this after sitting for about 6 or 8 months any suggestions the truck has almost 425,000 miles on it could it be the head gaskets are finally giving up

 

Did you "Burp" the cooling system to remove air? The way to check for bad head gaskets is to remove rad cap and let the engine run.Watch for constant bubbles,which means compression gases are getting into the cooling system

 

I've tried to burp the cooling system at first I thought the heater core was stopped up and was causing the problems but after bypassing it the problem continues so I'm back at square one I will probably just retire the truck and use it for the farm now it's not reliable enough for.me to drive a hour and a half back and forth to town

 

I have a 1998 ranger 3.0 that I recently flushed the coolant. I have filled the radiator up 2 times after driving it 2 times and the fluid level is about 2" down from the neck of the radiator even after topping off both times. Is the coolant suppose to be right at the bottom of the neck of radiator or is it normal for it to be down that much.

 

Your Ranger uses an Overflow system, so coolant level should be at very top of rad, 0 air in rad
When you heat any liquid it expands in volume
Coolant is no different, this is where the cooling system pressure comes from, expanding coolant as it heats up.

Radiator cap has TWO valves, larger valve(big spring) is set for 14-16psi pressure.
When coolant expands pressure in radiator goes up, when it gets to 17psi, big spring is pushed open and hot coolant flows OUT to overflow tank, though the Overflow hose, until pressure is under 16psi, then big valve closes again.

After engine is shut off coolant cools down and pressure goes down as coolant shrinks.
If coolant was pushed out to overflow tank then pressure in radiator will drop to -1psi and SECOND smaller valve in radiator cap will be pulled open and suck coolant from overflow tank back into radiator.
This keeps radiator "topped up" to the very top, 0 air

On the overflow tank there are HOT and COLD lines, so it is normal for hot coolant to be sent out of radiator to overflow tank, and then pulled back in as engine cools down.

So daily back and forth coolant flow

Overflow hose goes into the BOTTOM of the overflow tank, there is a reason for this.
If there was air in the radiator then when coolant warms up and big valve opens the AIR is the first to be pushed OUT to overflow tank and it will bubble up to the top of the overflow tank and is out of the radiator and out of the system, so self purging system.

But the overflow tank needs to be kept clean of debris because the overflow hose is at the bottom of the tank.
If it gets blocked by debris then coolant can flow IN from Rad(17psi) but can't be sucked back in TO Rad(-1psi)
If tank is blocked then air will be sucked back in from hoses or any smaller leaks in the system.


So check rad cap, small valve could be bad
Check overflow hose, needs to be air tight, any small crack will allow air to be sucked back in instead of coolant, air is easier to move than coolant.
Clean overflow tank

 

Thanks for your kind reply. I do understand the expansion and back and forth coolant from radiator to overflow. However, isn't the coolant level suppose to be right at the bottom of the neck of radiator when engine is completely cooled down. When I take the radiator cap off after sitting all night I should be able to stick my finger into the hole and touch coolant right. In other words just under the neck of radiator. Please correct me if I am wrong just inherited this truck from my Dad.

 

Ron, I have completely flushed out my coolant on my 98 ranger 3.0L Ford said that my whole cooling system holds 16 qts. so after draining the radiator only several times with distilled water I was able to determine I could put 2 gallons of water into the radiator after it was completely drained. So I thought if I could put 2 gallons of coolant Preston II into it that would be a 50/50 mix right. However, I just sucked up some coolant from the overflow tank to test it and it only tested to +10 degrees and looked very clear more like water then yellow/green Preston. This setup has a full 2 gallons of Preston in it so what should I do.

 

Coolant level in radiator after heat up and cool down should be at the very very top of radiator, NO AIR at all
Cap off and bottom of cap should be wet with coolant, no air at all

Overflow tank should be filled to COLD line when engine is cold of course.

Then after driving for 15 minutes or so the temp gauge on dash should show just below 1/2 way, 190degF, 1/2 way is 210degF
If it is lower then thermostat is not correct or stuck open
Stock thermostat is 192 or 195degF, either is fine, NOT 180degF

If coolant temp gets to 190degF then there should be some flow to overflow tank, won't be much but it should warm up a bit and level should now be above COLD line.

If possible drive up a long hill, that will heat up engine to 210degF, about 1/2 on the gauge, that will cause more flow to overflow tank.

Then shut off engine and wait for it to cool down
Pull off cap and it should be full to the top, no air at all

 

Ron, Can you tell me how many quarts of coolant is in the Ranger 3.0L Total coolant including the block, heater core, and radiator. The reason is because after I flushed out the whole system with water only 5 times with draining the radiator each time and filling it up with water, I was able to determine that I could put 2 gallons i.e. 8 qts. of water into the radiator to fill it up to the neck of radiator. So what I did was on the last flush, I drained the radiator completely and put 2 full gallons of Preston II coolant into the radiator. After Ford told me that the whole system holds 16 qts I thought I was perfect with the 50/50 mix since I was able to put 2 full gallons of concentrate into radiator. However, after doing all this I tested the antifreeze and it only test to +10 degrees and the coolant I sucked out of the overflow to test it looked more like water then yellow/green Preston. How can this be if I put a full 8 qts of concentrated Preston II into the radiator. What this is telling me is the whole system is way more then 16 qts. because if I put 8 qts. in it should be very close to a 50/50 mix and test at least down to -30 degrees.

 

Ranger fluid capacities seen here: Ford Ranger Fluids & Capacities

Radiator coolant does not circulate to the engine until thermostat opens at 190degF and only after a few minutes at 190degF the overflow tank will start to get some coolant flow.
If the overflow tank just had water in it then it will take several drive cycles for it to get to 50/50 mix as it does not have "circulation" just some coolant in from rad and then back to rad on cool down.
You generally want to use 50/50 premix in overflow tank because of this, i.e. don't top up overflow with water only, you can but it just takes time for it to balance out to 50/50

 

So basically you are saying take it for a long ride right. I just thought if you drove it 10 miles that would be enough to mix it up. I did look it up and the total capacity is 15.2 qts. So if I put a full 2 gallons of concentrated preston in I should be good. That's very close to a 50/50 mix. The only problem I had before getting this info was when I tested it it was only testing to +10 degrees and the February Temps were still getting down below freezing so I went to the store and bought another gallon and only drained about a half gallon out of the radiator and filled it up with half gallon of Preston. I guess this will put it closer to a 70% preston and 30% water. What I was told is that is ok just don't go more then that. I am confident after reading your last response that I did not drive it enough.

 

It is drive cycles that mix the over flow tank
1 drive cycle is cold engine, fully warmed up engine, cold engine
I would expect 3 to 5 drive cycles to mix overflow tank

Long drive mixes the coolant and water in the engine, radiator and heater core.

It is best to add pre-mix to overflow tank

Drive cycles are also important for several systems tests the computer runs

 

Ron, You seem to be very knowledgeable about Rangers. I am installing new upper control arm with new ball joint. I noticed when I removed the bolts with the camber washers, the ones that have the angles on the plates that the drivers side is facing up and the passengers side is facing down. Correct me if I am wrong but aren't they both suppose to be facing up. The truck drove fine before I started this and the alignment seemed fine. Just ready to put it back together and don't know what to do.

 

I have a 1998 ranger 3.0l 2wd that I am installing new upper control arms with new ball joints. However, when I took the camber washers and bolts out of the arm the plates that have the angled tops to them were facing up on the drivers side and facing down on the passengers side. Correct me if I am wrong but aren't they both suppose to be facing up. I am at the point of putting them back together but don't know what to do. It drove fine before starting this job and the alignment seemed fine also. So not sure if this is normal or should I put both sides facing up.