I'm still in the detective stages of this. It started running a bit rough and then started to get warmer than usual with regular driving. Has new plugs. Old ones looked OK just worn with age.. I haven't fully diagnosed it as head gasket yet. I did a compression test and wasn't too bad. I will be repeating that today. I did a chemical reaction test which came negative but it was done after using a head gasket product. Possibly not enough blow by to register the first time. Not seeing oil in my coolant or milky oil. A bit smokey after sitting at idle. (could video that today) Engine still gets warmer than it should when running it on anything other than flat roads. It was losing coolant at the water pump so it was replaced. Thermostat replaced as well. Blows hot air in the cab no problem. Replaced the ECM not long ago and the only code it's throwing now is Catalytic converter out of tolerance. Previous to that I did have a misfire code but haven't had it throw that code since replacing the ECM. Engine still gets warmer than it should when running it on anything other than flat roads. Will try to backward flush the coolant today, repeat compression test. repeat chemical test at the radiator for combustion gas. test thermostat on the stove with an accurate thermometer. Already put a new fan clutch on it. Seems like it should be louder when it's hot like when I first fire the engine up but both the old and new fan clutches behave the same. (I do have an E-Fan I could throw on). Checked the temps while driving with my scanner and the dash gauge seems to be reading true. This is the 4.7 SLT Dakota.

 

Redid the compression test this morning and then did an oil change. I run synthetic. I will re-do the chemical reaction test on the rad. I do plan to flush the rad as I found something weird in it. Maybe just some paper towel fragment from cleaning surfaces during water pump and thermostat installation.

 

Just a chunk of paper towel or maybe something you've seen in coolant before? Feels almost like lint from a laundry dryer to the touch. soft and fluffy fibers. Maybe nothing.

 

Plugs are a couple weeks old. Installed when I did the first compression test.

 

Cooling flush revealed this substance clogging the radiator. I flushed with a garden for a good long while. Any ideas what might it might be? Was I dumb enough to drop some paper towel in there? What might work to break it up and break it down?

 

Careful, you got the cylinder order wrong. Driver's side is odd (1-3-5-7), passenger side is even (2-4-6-8). Compression looks good.

Could be corrosion on the radiator. Might be CLR and flush time. No idea what the little fuzzy is.

How's your PCV valve?

 

Thank You. I am aware the numbers don't match firing order. I was too lazy to look them up but I wanted reference to which plug was in which hole. Now I see odd and even wouldn't have been much effort. After flushing with clean water, I added 2 quarts of Prestone flush to straight water and after another day of driving tomorrow It's going to my friends shop for compressed air / water flush. Driving today the temps were down a bit. Fingers crossed. PCV valve was new last month. I will check it as well to make sure its working.

 

The Prestone Flush worked magic. It grew a new radiator and called my buddy to install it. Temps are stable. Now on to the rough idle issue.