2003 5.4L recent purchase is overheating after sparkplug change.

[Hamfisted]

This tool worked for me on my Expy. Spray some WD40 or something on the pipe to lube it since it probably hasn't moved since it left the factory.


https://www.amazon.com/Assenmacher-...=Lisle+line+disconnect&qid=1589673123&sr=8-48

 

[Lee_H]

Thank you for the wrench information. I tried thin (less than 0.020") flashing to see if something would get pass the fitting, it wasn't working either.

Plan on removing the oil filter and while the radiator is out see if I can reach the suction hose since I bought that (thinking the old hose way be collapsing) and the hose is attached with a worm drive clamp. I have spares of those. The main feed from the over flow tank looks fun, I guess the power steering pump needs to be out of the way as well. Didn't buy that one although that hose is only pressurized.

The threads match from old to new on the fittings. I'm not sure I like unbolting fittings on the new radiator but at least getting the truck's engine back running will tell if the head gasket is the real bad guy or did I fix things for awhile.

I'm missing my 1971 Torino every time I lift a wrench towards this vehicle. Parents bought it new when I was eight and nine years later I got my driver's license in it. Drove it until about 1992 then bought a Ranger. It is in retirement in the garage, plan to work on it when I retire (still many years to go).

 

[TomB985]

Now that's frustrating, I forgot these required a special tool to get off. This is what the service manual calls for: https://rotunda.service-solutions.com/en-US/Pages/ItemDetail.aspx?SKU=307-441

 

[Lee_H]

OK, I manage to change the suction hose while the radiator was out. I can see that this is the only way you can reach this hose is when the radiator is being changed. The side radiator holders did not want to come out attached without banging into the air conditioner tubing. I unfasten them first and removed the old radiator without them. On the return trip I attached the passenger side and placed the driver's side holder in place and eased the new radiator in. While juggling with the holders I almost forgot the shroud. With enough working parts back and forth it went together. Getting the little square nuts in the top of the radiator to co-operate was some work. Now to the bottom. I removed the transmission cooler fittings starting with the long tubing on the passenger side. Sprayed oil on the line until the old fitting on the truck spun around reasonably well then covered the threads in blue (removable) thread locker (to help seal). Did the same with the driver side connection then attached the supply hose. The rest of the stuff went together normally. Filled the over flow tank with two gallons of concentrate anti freeze and two and a half gallons of water. Fired it up with the cap off, got some air burping out as it slowly warmed up (still had the thermostat missing). ECT from the code reader went to 130 deg. F and I shut it off while putting tools away. Put the cap back on and drove it around, took awhile (12 minutes) for the dash gauge to move in the center. Pulled over and checked for leaks, none found. Continued to drive for a total of 35 minute mostly stop and start traffic. Dash gauge stayed centered. Code reader's ECT measured between 210 and 220 deg. Not sure if this is normal but it was pushing 240 to 250 degrees when over heating. Still will run some short trips before fully trusting it again. At that time I'll replace the open thermostat with the new 180 thermostat. Note: I checked the oil again for signs of water or anti freeze. Nice amber color that I could read the MIN letters though. Was bracing for brownish oil from a leaky head gasket. I hope I dodged the head gasket project for now. If someone can confirm the ECT temperature was normal or not (210 to 220 deg F) from the code reader that will help.

 

[Don Hall]

210-220 is higher than normal, but you mentioned stop-and-go traffic, so
that could be normal.

Check the siphon activity. You know that when the engine heats, coolant is
expelled into the overflow bottle. During engine cool-down, the coolant is siphoned back into the radiator. If this siphon activity is not occurring, air is entering the cooling system through a faulty hose, connection, or ruptured head gasket. Carefully measure the coolant level when cold, and hot.
I'm not suggesting that you check the radiator, which is under pressure when hot, but the level of the over-flow container, which is never under pressure. You should see the coolant level increase in the over-flow container when hot, and decrease when cold.

 

[CaptainKrunch]

I use an obd 2 Gauge reader thing that mounts inside the car. It shows me running between 175 and 184 with it mostly hovering right at 180 degrees. That's with 67 degrees and below air temp. I have not checked it with higher air temperatures.

That's with stock t stat and maintaining the cooling system.

 

[TomB985]

Even in stop and go traffic 210–220 seems high to me. I've never seen get that high towing my 3500-lb boat.

I believe the factory thermostat is 192°. I wouldn't go lower than specified, it could get stuck in "warm up" mode and run rich which can cause problems over time.

 

[TomB985]

Just stumbled across this while digging around online, it's the relevant section from the factory workshop manual.

 

[Lee_H]

Thanks for the check sheet, I haven't driven the truck again yet. Maybe tonight. Fluid level is a bit high now since I was expecting a bit of air to work it's way out. Although the anti freeze is new, the engine oil is still looking good (that has been unchanged from spark plug change to now). So I still have hope no gasket problems. I still wonder how well it ran with a bad pump and a supposedly plugged radiator until now. How often is the sensor itself off? When the truck overheated it was obvious with steam out of the hood and the temperature gauge right on "H". I don't have an old reading of the ECT to compare. The last run the temp. gauge reading was solid in the center. I hope it stays that way.

 

[TomB985]

Thanks for the check sheet, I haven't driven the truck again yet. Maybe tonight. Fluid level is a bit high now since I was expecting a bit of air to work it's way out. Although the anti freeze is new, the engine oil is still looking good (that has been unchanged from spark plug change to now). So I still have hope no gasket problems. I still wonder how well it ran with a bad pump and a supposedly plugged radiator until now. How often is the sensor itself off? When the truck overheated it was obvious with steam out of the hood and the temperature gauge right on "H". I don't have an old reading of the ECT to compare. The last run the temp. gauge reading was solid in the center. I hope it stays that way.

Easy way to check the temperature sensor is to let the truck sit overnight and see what it reads before starting. Should be within a few degrees ambient temperature.