1999 ford explorer v6 4.0 sohc
 

Hello

Can someone help this guy. Have a ford explorer sport with 4.0 sohc vin e
engine. Trouble started when replaced water pump. Now in 1999 Ford also
had a 4.0 ohv vin x engine. Engine overheats but in a strange way. Does
anyone know if possibly the water pump the mechanic put on my truck was
the wrong one? Maybe the one for the ohv instead of the one for the sohc.

Now in the mean time I've put in five new thermostats and I beleive they
were putting in the wrong ones. Putting in the ohv ones instead of the sohc.
I just put in a brand new one and it still isn"t right.

Question does anyone know if the water pumps for the two different
would even bolt up to each other.

I'm not to mechanical so go by what they tell me.

Be patient as I try to explain what it did this morning after the fifth
thermostat. It's been in the shop at least five times for this problem.
It's been checked for head gasket leaks at least three times. Head sup-
posedly OK.

Heres what it does. Start up leave home. Drive approximately 3 to
5 miles. Usually have heater on so I can tell when going to act up. Heater
temp. will start to cool. Drive another 3 to 5 miles heater temp. cools more.
Another 3 to 5 miles temp. gauge starts rising quickly. Red light on dash
comes on so pull to side of road. Put explorer in neutral and rev up engine
couple of times and gauge generally drops quickly. Put back in drive and
everthing is fine after it does this. Would drive it 500 miles after this.

???? Any ideas need some help

Pleas E Mail at lessel@ecenet.com

My guess would be that either the thermostat is backwards or air in the thermostat housing is causing it not to open in time.

I bought a thermostat at the parts store and noticed it didn't have a small hole that the original had. So I bought a Ford Motorcraft thermostat which has the small hole, allowing a little coolant to flow even when it is cold. This allows the coolant to flow across the thermostat so that any air will escape and the thermostat will get the warm coolant sooner.

Another reason that the thermostat might not open in time would be if it was installed backwards. The part that opens the thermostat must be in the hot water or it will not open at the right time. Once the thermostat opens, the water will continue to flow until it cools down.

The heater core basically by-passes the thermostat, so it will not necessarily react the same as the coolant flowing through the thermostat housing.

There are other possible problems such a clogged lines or hoses inproperly routed.

I don't know if the water pumps are interchangeable for the two engines.

I have a 1999 Explorer with a 4.0L(X) OHV. At 90,000 I blew both heads. Ford dealer replaced both heads. The same day I drove it home within 3-5 minutes the truck overheated. Let it cool down, and drive for 3-5 minutes and it would do the same thing. Ford ended up putting on the wrong heads, I asume the 4.0L OHC heads. Ford replace everthing under warranty even though the truck was out of warranty.


Is your truck using any antifreeze?

Can't make that mistake. OHC heads would not work on OHV engine.

Wrong gaskets maybe...

1999 Ford Explorer SOHC
 

Wanted to add to symptoms for v6 SOHC engine. It also when the
coolant level is full. Such as after putting a new thermostat in.

It will push the coolant into the overflow tank. Won't draw it back out.

And if I leave the radiator cap open it will still make the gauge move
towards overheating. But will not go all the way. Also when it's going
to overheat the heater will start to blow cool air. It will be cool for about
two miles. Then after pull over and rev it up a couple of times heater air
turns warm gauge drops and I could drive 500 miles without it doing it
again. Had it to at least 4 mechanics. Heads check out good?????

Ford told me they put the wrong heads and had to reorder them. Took them just over a week to complete. Two weeks in all the vehicle was laid up. But they gave me a 2002 Explorer with a 4.6L. Wow, I know what my next explorer will be!:-X10

Give this a try. When the vehicle is cold (let it sit overnite), remove the radiator cap, hopefully the coolant is down a little, with a second person start the truck and rev beteween 2000-3000 rpm with the heater full blast. Watch the coolant and have coolant ready to add as the level drops, wait until the thermostat opens, two ways you will see this, 1. You will see the coolant start flowing through the radiator. 2. Keep your hand on the upper radiator hose, when the thermostat open the hose will get reel hot, the level will drop in the radiator, add antifreeze and cap it. Make sure the rpm's are up like I said and it will pressurize the system. Works best with 2 people.:)