1995 Escort overcooling problem

[willye]

Hello, I need some advice from someone who has information on this very unusual problem. My 95 Escort 1.9L is not warming up -- I investigated the thermostat first. It has been replaced with a 192 degree thermostat. The problem persisted after this was done. I then decided to get a gauge to replace the sensor to see exactly what the temperature is when warmed up. The coolant is running a consistent 170 degrees when run for 5-10 minutes or more. This gave me exact data to look at instead of the Escort gauge. Next I removed the thermostat housing again and sealed the surrounding area around the thermostat with silicone high temp RTV. The housing has 2 thermostat by pass orifices which I plugged with a custom made bolt cut to fit and more RTV sealant. These are plugged tight! I bolted it all back up and it still runs a steady 170 degrees with a 192 thermostat in it. By the way -- I checked the thermostat opening temp in a pot of water and it opened right at 192 degrees. It is an aftermarket thermostat. Common sense tells me that water is by passing the thermostat some how. Can anyone shed any light on further steps to make this thing run at 190 degrees? Thank you!

[todd.d.noland]

I hope some one can reply to this, Ive had this car for 1 year and ive never needed the heater till now so i never new it would be a problem to overcool but It sounds like you have the same problem that i cant figure out too.

[willye]

Originally Posted by todd.d.noland

I hope some one can reply to this, Ive had this car for 1 year and ive never needed the heater till now so i never new it would be a problem to overcool but It sounds like you have the same problem that i cant figure out too.

Todd, I have done quite a bit of research on this problem and am soon to find out if I have solved it. When the colder weather sets in I will know if I have enough heat to survive it.

I have put in a SUN temperature gauge/sensor to monitor the engine temp. Since the temp sensor is in the heater hose, this poses a problem if the coolant does not flow well through the heater circuit. I verified that I have good flow first and replaced the thermostat, water pump for good measure. I only replaced the pump since I have had the car in storage for 6 months and replaced the timing belt during this time.

So far, the escort warms to about 170-180 pretty easily. It should be around 190 though. Since the sensor is in the heater circuit. I believe I am getting a cooler reading than what the engine actually is because I did a digital thermometer check at the radiator outlet and it runs > 190 when the temp gauge says 180. I have used 3 different temp gauges and this one is the most expensive -- so i am pretty sure it is accurate. I am not sure how to get more coolant flow past the sensor to keep it accurate with the Engine. - I dont like this design for monitoring engine temp. But is what Ford came up with.

[Arnoldtheskier]

Engines not reaching operating temperature:

lol..is the system full???

Cold climate..is there excessive air circulation over the engine?

Not enough heat?Is the circulation good(throughout)? Are the heat doors etc, open?.

Test and replace the thermostat with a KNOWN good one.
Disable the fan(w.pump too if easily done)
Do this at an idle.
Make SURE! you know what you are doing!! what you "knew" beforehand can be very wrong..you can end up with an EXTREMELY overheated/damaged engine..Or the potential for serious burns REAL FAST!
AND .. have an accurate temperature gauge ADDED to the system..AND!!! that this sender is SUMERGED in coolant.Find a place that is close to the coolant in the block/head..forget the idea of the "remote" sender in some huge long heater hose affair..where there is NO coolant and NO circulation..you'll be watching the gauge at 0 as the engine gets toasted.
Begin disabling the cooling circulation system:
Begin at the rad hoses.Upper first.Easiest way is with a VERY good hose..and a pair of "pinch off"(available specially for this purpose)pliers.OR There are simply too many ways/variations to do this other ways to get into...OBVIOUSLLY if the hose is not that good you know what will happen.Ditto for the hose being clamped too close to the outlet spouts.

Once you see that the engine can indeed reach operating temp.it is pretty easy to work backwards.


Just remember:KNOW what you are doing..this method flat out works..some engines can get SERIOUSLLY HOT!! REAL FAST!..when that gauge hits 140 or so..OR is rising REAL fast..shut 'er down NOW!..diddling around as the gauge hits 190/200..can cause the temp to "flash" WAY beyond that..when you shut it down.

[willye]

I am convinced that the engine is warming just fine. I also know that the heater core is ok - I ran some CLR through it and it came out very clear with little debris.

The temperature appears to be affected by the sensor being in the heater hose. The question is - how do you get the temp in the heater hose to equal the block temperature so the sensor reports a higher temp?

[Arnoldtheskier]

The temp.sender in the heater hose..well it is not ACTUALLY in the "heater" hose..it is in a "T" fitting with another sender..(both submerged in coolant)a foot or less from the actual thermostat which is IN the block submerged in coolant.True..this hose does then run to the heater.There will be minimal difference in these actual temperatures.The only way you can actually do this is to find a fitting in the block or the head..right there..and tap into it..OR..get an old housing..tap into it for a sender and then use your pinch off pliers to keep the coolant there as you measured the temp.and compared it to the other sender.I feel that you are concerned that because of the factory sensor..it is lowerring the engine temperature too much.There are sensors for the actual gauge in the car.Another to turn the fan on/off at pre-determined temps.If your fan does not come on look elsewhere..read my previous post.I know it can be bafling..but remember.There are almost NO vehicles that come from the factory with poor heat,defrost..yes there are a few of course.This is pretty much guaranteed a problem that HAS DEVELOPED WITH AGE..wear and tear.

[willye]

I am fairly certain the engine temp is ok, and the temp in the heater hose is lower. I am wondering if sluggish flow through the heater host may be the cause. The port for the heater hose is not very large in the thermostat housing.

I replaced the water pump so this is ok. The flow through the core is ok. I checked that too. If the flow is sluggish, then the temp in the heater hose may not keep up with actual engine temp.

Any thoughts?

[bebopinbill]

Originally Posted by willye

I am fairly certain the engine temp is ok, and the temp in the heater hose is lower. I am wondering if sluggish flow through the heater host may be the cause. The port for the heater hose is not very large in the thermostat housing.

I replaced the water pump so this is ok. The flow through the core is ok. I checked that too. If the flow is sluggish, then the temp in the heater hose may not keep up with actual engine temp.

Any thoughts?

I know exactly where you are comming from, I am disapointed that you found plugging those ports in the thermostat housing did not work, it was something I wanted to try but was a little nervous. I am also suprised the problem persists through to 95, mine is a 93. Please keep me in the loop if you discover anything.

[willye]

I have a SUN temp gauge in the normal port that would contain the gauge sensor. I am getting a typical range of 160 to 180 degrees with the trend being toward 160 most of the time.

After sitting at a stop light and then run it through the gears, the temp will rise from where it was while sitting. This tells me that the increased rpm of driving has forced coolant into the heater circuit more than it was while sitting at a light. Since the temp sensor is in the heater circuit, it is picking up this increase.

The problem here is that if this is the case then this tells me the heater circuit does not always have actual engine temp. I have looked at a spare thermostat housing that I picked up a salvage yard and noticed that the heater hose orifice is relatively small and off to the side of the housing. This may provide enough restriction to impede flow of coolant to the heater circuit.

Why doesn't the temperature rise to around 190 when under normal driving? Does anyone have actual driving temperature readings from a real gauge? Any suggestions?

[Snow93]

the only real gauge i have is the one that comes with the car.. sits at O, so round 180 i suppose. but my thermostat aint mounted in the heating pipe, thats the only guess i have as to why it gives an off reading like that-its locaton.. if you wanted you could probly move it at an emense expense and pain.

[shakerr]

Originally Posted by todd.d.noland

I hope some one can reply to this, Ive had this car for 1 year and ive never needed the heater till now so i never new it would be a problem to overcool but It sounds like you have the same problem that i cant figure out too.

Hi,,,,My 93 runs cool also,,and when I went to replace the thermostat with a 180,,,I pulled the hose to the top of the engine and could not find a rad thermostat..?? Do you know if I am looking in the right spot ?

thanks in advance...

[dougand3]

Originally Posted by shakerr

Hi,,,,My 93 runs cool also,,and when I went to replace the thermostat with a 180,,,I pulled the hose to the top of the engine and could not find a rad thermostat..?? Do you know if I am looking in the right spot ?

thanks in advance...

The T-stat will be in a housing attached to block...the rad hose will be attached to this housing....you must remove the t-stat housing to get to the T-stat. I speak of the 1.9L '93 engine but I'm sure the 1.8L is similar.

Willye, I'm bummed your "RTV plug in the bypass cylinders" didn't work...as I thought about this same problem, I KNEW your experiment would work....bummer.

[willye]

I have a junk yard thermostat housing that I have had for some time now but have not installed. There did not seem to be any difference between the one in the car and the one I picked up at the bone yard.

I noticed a symptom that became a clue. When driving normally, the temp would range from 155-170 but mostly at the lower end. Then, after sitting a stop light for 3 or so minutes, traffic would begin to move and I would run the escort through the gears to get up to speed. I noticed on many occaision that the temp would go as high as 190 and stabalize around there. With the sensor in the heater hose, any restriction to coolant flow could give a false reading on temp.

I looked at my bone yard housing and took notice of the port where the coolant flows to the heater hose. The coolant entrance in the housing is rather small and the thickness of the outlet pipe is thick, reducing the size of the coolant passage inside. I decided to try an experiment in modification.

I drilled out the outlet pipe to a size or two larger to allow more coolant to flow. At the coolant entrance in the housing, I smoothed and widened the opening to allow less resistance for coolant flow to pass through.

The bottom line is it seems to have improved the coolant flow because now my temp runs around 180 consistently. The engine is a little slow to get to operating temp but that seems to be the nature of this engine.

I would like to know how others have solved this problem. I am not sure that I am finished but the results are encouraging.

[willye]

I would like to know how fast your escort reaches normal operating temperature. Mine take longer than I would like to reach about 180 degress according to the SUN gauge. It takes about 15 to 20 minutes of normal driving to warm up.

[Snow93]

20 minutes? today-with normal driving, the rpms never moving past 1200, took about 10.