98 Contour overheating with new t-stat & w-pump

[markdrummond]

Hi all. My 98 Contour (4-banger) started overheating while I was driving to Ottawa other day. My nephew-in-law (mechanic) figured it was probably the thermostat (original) so I took it in to a shop and sure-enough the thermostat was stuck shut.

So they put a new t-stat in it but that was not the end of it. It was still overheating so they figured the water pump was busted. Yep. So they replaced that too.

Once they had replaced both components, they took it for a drive and said it was all fixed up. This is about 36 hours after I pulled in. They loaned me one of their company vehicles to finish my overnighter to Ottawa.

Anyway, I pick the thing up and start heading back home. The whole way there (about 100km) the temp needle slowly creeps up till it red-lines again!

So both the thermostat and pump have now been replaced, but the bloody thing is still over heating. There is no coolant flow at all. Driving it from my place to work (7-10 minutes or so) pushes the temp needle up to the "L" in NORMAL which is just shy of red-line. But the coolant in the tank is still ice-cold!

I just don't get it. If the engine is completely cold (say after a night in our current -35 degree celcius weather) and I fire it up, the tempurate needle climbs to the "N" in NORMAL in about 15 seconds. After about 60 seconds, it is already almost at the 1/2 way mark. I've never seen it warm up that fast before.

Any ideas out there?

Mark

[brooster]

You're probably reading superheated air temp in the block and not actual coolant temp since the coolant is still cool to the touch. You may need to bleed the air from the cooling system and top off the coolant level. Notice if your cooling fan is coming on prematurely while the radiator hose(s) are still cold/cool. This is a good indication that there is air in the system.

[markdrummond]

Any idea how to do that? The mechs that replaced the thermostat and the pump said they bled the system twice. Then they told me to check on the coolant level once I got home and the engine was cool again. So this morning I popped the hood and the coolant tank is actually overfull (above the MAX line while cold). They seemed to indicate that you bleed the system by driving it. I've driven it a couple times since then (to and from work - short trip) and still the same thing (apparent fast rise in temperature), and an overfull coolant tank.

Don't get me wrong, I don't doubt you. It certainly seems to make sense. Does that mean that air in the system prevents the pump and/or thermostat from functioning properly? Would that also mean that the temperature reading I am getting is misleading and the engine is not running as hot as it seems? (Especially in the extreme cold spell we are under right now?) Where exactly does the temp gauge take it's readings from?

I have serious concerns about any possible damage due to overheating. I like my Contour!

Thanks,

Mark

[brooster]

No I can't tell you exactly how to bleed it. I work on so many different makes/models, makes it difficult to remember them all.

Very few of the newer models if any can be adequately bled by driving them. Patience I've found is the key. Basically, with the engine cool or cold, remove the radiator cap if it has one. Remove the cap from the reservoir if it does not. Fill the radiator and start the engine. Let it idle and keep a jug of coolant handy. Watch the radiator/coolant reservoir for bubbles floating to the top, while monitoring the temp gauge. As the gauge reaches the R/M in normal, the thermostat should be about ready to open. When the thermostat opens, the coolant level will drop rapidly and steam will usually escape out the filler neck. Add coolant slowly to allow air to escape as you're adding coolant. Make sure the heater/ac is off, and not in defrost mode, otherwise the cooling fan may operate when you don't want it to. If the cooling fan comes on prematurely (hoses are still cold), turn off the engine and allow a few minutes for systems to equalize and give the air a chance to escape. The coolant may overflow if air is trapped below the coolant level, so be cautious for not only the spills, but not to get burnt. Continue this process until, the top radiator hose is hot, indicating the thermostat is open, temperature gauge is slightly below halfway the gauge, and the radiator is full. With the engine running install the radiator cap and continue monitoring until the cooling fan cycles on and off twice. The gauge should not go higher than slightly above halfway. If you are filling the system at the reservoir, do not fill it above the FULL HOT line.

Air in the system limits the effectiveness of the cooling system to do its job the same as air in the brakes. The temperature gauge typically will take its information from the coolant temperature sensor or sending unit located in the head, the thermostat housing or intake manifold. Superheated air trapped at the temperature sending unit can easily cause the gauge reading to be super high even though the actual engine temperature is less than that necessary to open the thermostat.

[takeum]

Originally Posted by markdrummond

Hi all. My 98 Contour (4-banger) started overheating while I was driving to Ottawa other day. My nephew-in-law (mechanic) figured it was probably the thermostat (original) so I took it in to a shop and sure-enough the thermostat was stuck shut.

So they put a new t-stat in it but that was not the end of it. It was still overheating so they figured the water pump was busted. Yep. So they replaced that too.

Once they had replaced both components, they took it for a drive and said it was all fixed up. This is about 36 hours after I pulled in. They loaned me one of their company vehicles to finish my overnighter to Ottawa.

Anyway, I pick the thing up and start heading back home. The whole way there (about 100km) the temp needle slowly creeps up till it red-lines again!

So both the thermostat and pump have now been replaced, but the bloody thing is still over heating. There is no coolant flow at all. Driving it from my place to work (7-10 minutes or so) pushes the temp needle up to the "L" in NORMAL which is just shy of red-line. But the coolant in the tank is still ice-cold!

I just don't get it. If the engine is completely cold (say after a night in our current -35 degree celcius weather) and I fire it up, the tempurate needle climbs to the "N" in NORMAL in about 15 seconds. After about 60 seconds, it is already almost at the 1/2 way mark. I've never seen it warm up that fast before.

Any ideas out there?

Mark

DUDE,, WORD for the wise..... Have your Catalyst converter checked by a professional or take it off and inspect yourself,,, If it is anything like mine was at 100,000 miles,, you need it replaced or cleaned out... causes major overheating problems,, exhaust backs up through the tailpipe and goes directly back into your engine, good luck

[takeum]

Originally Posted by takeum

DUDE,, WORD for the wise..... Have your Catalyst converter checked by a professional or take it off and inspect yourself,,, If it is anything like mine was at 100,000 miles,, you need it replaced or cleaned out... causes major overheating problems,, exhaust backs up through the tailpipe and goes directly back into your engine, good luck

I had a 95 contour with the same problem,,, overheated one day going to visit someone,,, I changed the thermostat and the water pump after the overheating problem thinking that I solved the problem,,, after installing the parts,, I noticed the car never seemed to read better then half way,, mostly read between 3/4 and full on HOT,,,,I even changed the sensor thinking that it was the problem caused from overheating....man was I wrong,,,, changed cooling fans... direct wired fan so it stayed on all the time ,,, worked so it never fully overheated,,, but when I cranked the air on,,, that puppy got Hot fast,,, I ended up pulling the engine thinking something was wrong internally,,, bearing were good,,, and engine looked fried inside,, Just flat out caused from engine heat,, So I looked inside Cataylic converter,, and it was clogged,,,,I hollowed it and and replaced motor with exsisting parts from other engine,,,, worked fine ever since,, overheating was Gone,,, senors worked great,,,,,Pull off your exhaust and check converter,,,,,, look inside it and see for yourself,,,, 6 cylinder motors were sent a notice from Ford,, saying it was a recall,,, maybe they should have done the same for our 4 bangers,, but after 100,000 miles,, everything runs out of warrenty anyhow,,, way to Go Ford,,,Got my cooling fan recall at 110,000 miles,, thanks Ford , and my heat control switch problem after the fact as well,,,

[DUNCANS OFF ROAD]

Mark To Bleed The Cooling System Is Rather Easy As The Car Warms Up Uou Need To Take The Cap Off Of The Cooling Resevoir. After Doing That Sqeeze The Upper Radiator Hose. U Will Notice Air Purging From The System As You Do This.
The Coolant Levale In The Resivoir Will Also Drop. Add Mor Coolant As Neccessary. You Will Have To Do This Several Times. Once The Coolant Has Stopped Dropping Turn On Your Heaterto Allow The Air To Be Purged From Your Heater Core. Follow The Same Procedure. You Will Have To Do This Several Times . Repeate It Un Till The Water Pump Has Quit Cavitaing And Is Circulating The Coolant.once That Happens The Upper Radiator Hose Will Be Hot And When U Squeeze It You Will Not Here A Sloshing Sound.

[haque]

Hi,

I have a 1998 ford contour, and having the same problem. Would you please let me know how you got rid of your overheating problem. Which part should be changed or what to do. Thanks.

Jahirul
[email protected]