Couple of running/cooling questions

[jaycal]

1994 4.0 Explorer 150+k miles

My wife found she had a coolant loss problem about 2 weeks ago. Truck did get hot to lead her to checking the coolant. She started maintaining the coolant level in the bottle and continued to drive it with no issues for a couple weeks. The other night she ran to the store and when she came out found coolant leaked under the truck. I went and checked it out and found the plastic radiator had split above the lower hose. Topped of the coolant and she drove it home the 2 miles without it getting hot. It was late and she needed the truck in the morning so I replaced the radiator that night with a 2 core vice the 1 core that came stock. Other than the shroud fittment a little off (1 1/2" gap down the vertical edge on drivers side) figured 2 core would be better and it was all that was available at 10 pm.

Since then the truck
Runs rough almost like a miss
Still consumes coolant
Temp gauge "bounces" around between Cold line and middle of range
Temp does not get hot at all
Check engine light is on (not sure when that happened)

With some visual trouble shooting I found
Oil looks good on dip stick (not milky or creamy)
Coolant looks good (no signs of oil or bubbling when running or cold)
At start up it appears to have a little more than normal moisture from the exhaust pipe, and very light sign of white smoke.
No other signs of visual coolant leaks external

Some of the testing equipment and techniques are not my strong point nor do I have the equipment, but I have had motors apart on a few occasions.

Any help on where to go next would be much appreciated.

Thanks
J

 

[sholzy]

While refilling the cooling system did you turn the temp selector to hot? After refilling you probably had air trapped in the cooling system and could have ended up damaging your head gasket, hence the coolant loss, white smoke and miss. Check your plugs.

Also you could just be boiling your coolant after shutting off the engine or even while driving. The extra pressure created from the boiling will push past the thermostat and push coolant out the overflow tank. When the system cools down it will suck the remaining cooling back out of the overflow tank back into the cooling system. If the overflow happens while you're driving you may not even notice any leaks.

First thing I would do is refill the cooling system correctly while the temp selector is set to hot, then drive it to see if anything has changed.

 

[jaycal]

I did not when I originally filled the system. I went through and ran everything up to temp today with cap off and heater on after reading some other posts. Do I need to drain and start from scratch to get out trapped air?

J

 

[sholzy]

I did not when I originally filled the system. I went through and ran everything up to temp today with cap off and heater on after reading some other posts. Do I need to drain and start from scratch to get out trapped air?

J

No.

 

[jlove1974]

just a question:
what does the temp selector have to do with anything? All that controls is the air door to the heater core. This isn't a 1958 Chevy Impala.....there is no vacuum operator coolant switch like on ancient cars....it's just an air door control.

just FYI: to successfully bleed air out of your cooling system, your radiator needs to be higher than the highest point on the engine (usually the intake manifold).
Pull the truck up on ramps, running it from a cold to normal temperature with the cap off should do the trick. you'll see it puke the air out and you'll usually have to top it off w/ coolant.
Stick the cap on while its warm (not hot or boiling!) and let it cool. That should be it.

Also if you have a prestone backflush port plumbed into your heater inlet hose(everyone should have one with an old Ford...), you can open it when the truck is still on ramps, engine off, and cold, and coolant should run out.

 

[Big Jim M]

JLove raise the hood and make sure you don't have a cut-off in one of the heater hoses.. Many, many of our Rangers still have that coolant shutoff in the heater hose..
I KNOW it is oldtimey but the Rangers still have had that cutoff.. I KNOW for sure my 1999 still has one.
My 99 also has the vac operated gates... but they are for air circulation only, the actual heat is controlled by the coolant shutoff under the hood.
Big JIm