Overheating

P

PearlLSC

Registered
For the last several weeks, I've been getting low coolant message. I checked it each time, and added some coolant to the overflow resevoir, even though it didn't appear to be that low.

I was on my way to San Francisco on a fast road, doing about 80 or so when I noticed that my temp gauge was approaching the red mark. After a couple of minutes the alarm went off. I pulled over and had to wait for the car to cool off. After it did, I started home, but overheated again almost immediately. I took the overflow tank cap off. This worked by keeping the temp low because ther was no pressure, and though the temp was consistently high, I was able to get home.

I took it to my local mechanic, who diagnosed the thermostat, which seemed right to me, so I had it replaced. After that, I started to get low coolant messages again. The second time it happened, I parked it in my driveway and added coolant through the crossover at the top of the engine. I could see it fill up the overflow, and it looked full, so I closed it off and went on my merry way. Two days later I got another low coolant message. This time I added a gallon of distilled water (all I had at the time), again through the crossover. Once more it seemed to be full. The first time I added coolant, I didn't have the engine running, the second time, with distilled water, I did have the engine running, but didn't see any burping, as if there were big air bubbles in it. The coolant just flowed from both sides of the overflow, and down to the thermostat assembley. Everything seemed fine, so I buttoned it up and went my way.

Last night, I got another low coolant warning.

WHat have I been doing wrong? Do I need to keep the engine running until it's completely warm all the while dumping coolant into it? So far, it seems as though it's been full when I do that. Is there an indicator that I have the thing really full? Or is something else possibly going on here. I suppose I should have the heater running when I fill it, but is there anything else I'm missing?

Thanks in advance.
 
From the manual...

Cooling System--Filling

NOTE:
A 50/50 mixture of Premium Cooling System Fluid E2FZ-19549-AA (ESE-M97B44-A and ESE-M97B43-A) of equivalent and water is required to prevent damage to the cooling system.

1. Check all hose clamps for proper tightness. Ensure radiator draincock is closed.

2. Place heater temperature selector in maximum heat position.

3. Remove pressure cap from cooling system reservoir and fill plug from engine crossover tube.

CAUTION:
Do not fill cooling system through reservoir only. Coolant will not enter engine. Only reservoir and radiator will be filled and engine overheating will occur.

4. Add coolant into fill neck on engine crossover tube until coolant reaches top of fill neck on cooling system reservoir.

5. Reinstall cooling system pressure cap to reservoir.

6. Continue to fill cooling system at engine crossover fill neck until full.

7. Start engine, run at idle. Add coolant at engine crossover tube until full.

8. Reinstall engine crossover tube full plug.

CAUTION:
If engine temperature gauge does not move, coolant level is low in engine and must be filled. Stop engine, allow to cool and fill cooling system as outlined.

WARNING:
TO AVOID THE POSSIBILITY OF PERSONAL INJURY OR DAMAGE TO THE VEHICLE, DO NOT OPERATE ENGINE WITH HOOD OPEN UNTIL FAN HAS BEEN FIRST EXAMINED FOR POSSIBLE CRACKS AND SEPARATION.

9. Run engine until thermostat opens (coolant flowing through radiator lower hose becomes hot).

10. Stop engine and add coolant to engine crossover tube fill neck until cooling system is full. Reinstall fill plug.

11. Repeat fill procedure if necessary.
Click to expand...

I usually make sure the heater is on max and some warmth is detected to assure coolant flow through the heater core is achieved during the fill process. It is imperative the thermostat opens during the fill process.

I find it best after the fill process to leave the car sit overnight and top off the coolant resevoir the following morning as when the engine cools, coolant is drawn from the resevoir.
 
budpytko said:
AMAZING!!!! Funny how good things work after you read the instructions, eh? CONGRATS!
Click to expand...

I wish it were true. Unfortunately, correct filling procedure didn't solve the problem. The car overheats within 30 or so miles of being completely full. (Not once, but several times - so far I've put three gallons of 50/50 mix and two gallons of distilled water in the thing).

When it does this, the temp gauge climbs to the top of the white "NORMAL" range. Most of the time, it drops back down immediately after reaching the top, as if the thermostat had just opened, but today, it didn't do that.

The temp gauge at standard idle looked like this:

leaks_6.jpg


With the hood open, I could see coolant leaking out from under the coolanr resevervoir cap I assume the pressure in the system had reached 16 lbs. BTW, the coolant leaking out at the cap is cold, despite the temp gauge reading.

leaks_3.jpg


There was a good size puddle of coolant under the car as well:

leaks_2.jpg


The top of the radiator on the driver's side was cold, the passenger side was hot. WHen measured by my mechanic, the temp was 137 on the driver's side, 188 on the passenger side.

Since the thermostat was just replaced, it seems to me that the only two things left are a blocked radiator or a bad water pump. And before anyone asks, yes, the fan works.

Any suggestions?
 
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PearlLSC said:
Since the thermostat was just replaced, it seems to me that the only two things left are a blocked radiator or a bad water pump.
Click to expand...

It is rare for the waterpump to fail to actually pump. When you filled the system at the crossover, could you see the coolant circulating?

From your mechanic's temperature readings, I would suspect radiator blockage (or blockage somewhere).

Stupid question (gotta ask them when diagnosing over the internet), are you certain the T-stat is not backwards?
 
I would not assume that it's not the T-stat. I have purchased a bad one before.
You said in your first post that the fluid was running through the crossover tube, I would think that means the waterpump is working.
 
Be2lose said:
I would not assume that it's not the T-stat. I have purchased a bad one before.
You said in your first post that the fluid was running through the crossover tube, I would think that means the waterpump is working.
Click to expand...

Yeah, I missed that. True, any new part could still be suspect.
 
driller said:
Stupid question (gotta ask them when diagnosing over the internet), are you certain the T-stat is not backwards?
Click to expand...

I was thinking the same thing, but did not ask.(stupid me)

for a radiator blockage-Could you just take off the hoses and run water through the radiator to check for a clog?
 
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At work, I use an IR pyrometer to check radiators, heat exchangers, oil coolers, etc... for blockage. That's impossible to do on the Mark VIII due to the AC condenser and the fan. The best you can do is spot check the inlet/outlet and crossover tube. You can tell when the t-stat opens fairly easily.
 
driller said:
It is rare for the waterpump to fail to actually pump. When you filled the system at the crossover, could you see the coolant circulating?

From your mechanic's temperature readings, I would suspect radiator blockage (or blockage somewhere).

Stupid question (gotta ask them when diagnosing over the internet), are you certain the T-stat is not backwards?
Click to expand...

Yes, but only because all these symptoms were present before I had the t-stat replaced. And the shop I go to is run by three guys ranging from 82 (Carl runs the desk) to about 65. I don't think they're in the business to support themselves - I think they stay open to keep from getting bored. It would be a real surprise to find a thermostat in backwards out of their shop.

And yes, I could see the coolant circulating at the crossover, so that probably rules out the water pump.
 
Be2lose said:
I was thinking the same thing, but did not ask.(stupid me)

for a radiator blockage-Could you just take off the hoses and run water through the radiator to check for a clog?
Click to expand...

That's an interesting idea. I don't know how I would measure it, though.
 
driller said:
At work, I use an IR pyrometer to check radiators, heat exchangers, oil coolers, etc... for blockage. That's impossible to do on the Mark VIII due to the AC condenser and the fan. The best you can do is spot check the inlet/outlet and crossover tube. You can tell when the t-stat opens fairly easily.
Click to expand...

Actually, it works quite well. You can use a pyrometer at each end of the radiator at the top.

leak2a.jpg


This is the passenger side, but there is clear access to the radiator top.
 
I was talking of scanning the core to 'look' for blockages. Any blockage would appear cooler than the surrounding area where coolant is flowing. It is normal for the inlet side to be hotter than the outlet side, blockages or not.
 
driller said:
I was talking of scanning the core to 'look' for blockages. Any blockage would appear cooler than the surrounding area where coolant is flowing. It is normal for the inlet side to be hotter than the outlet side, blockages or not.
Click to expand...

Gotcha. Thanks.
 
Whats wrong with the good ole' hand on each hose test!?!?! :) Oh wait...theres 4 hoses!!!
 
Find out what brand of thermostat was installed. I went through 2 Stant thermostats that worked perfectly fine in a pan of water on the stove, but when in the car it would overheat. I finally bought a Ford thermostat from the dealer and installed it and the car cooled perfectly. (of course this was after replacing the water pump, swaping fans, flushing the radiator, etc....)


Chris
 
Well, it looks as though it isn't the radiator or the thermostat. It appears that the problem is a blown headgasket, which, while leaking no coolant into the oil, is pressurising the cooling system above the 16psi it takes to blow coolant out from under the resevoir cap.

Oh well....
 
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