Well about 20,000 miles ago I did a full flush with restore and restore plus and only distilled water. Then I added a coolant filter and deleted the egr and converted to cat coolant. After all this my unloaded deltas were 6-8 degrees. Recently I tought I had blown my head gasket but it turned out to just be the cap but I was told my coolant temps were low and my deltas were growing so I put in a new thermostat. The new thermostat got my coolant up to 186 - 188 (never higher than 188). Now maybe 800 miles later my deltas have gone through the roof they are 25-30 degrees, running empty on the highway at 70 - 75 mph. Any ideas on what could cause this? Do I need to replace my oil cooler again only 20k after putting a new one in?

 

Yes I remember hasnt been Long at all

Did you do all the cooling system flushing before the New OIL Cooler was installed right

How about ECT and EOT sensors do they report the Same temp within 1 or 2 degress of each other after a 12 HOUR COLD SOAK?????

 

Yes I did the flush before replacing the cooler. As for the cold soak, I have not looked at that, but I will let you know in the morning. Is it common for those sensors to go bad?

It has actually been 25,000 miles since the flush and new cooler

 

IDK if common or not for those sensor to fail

25K is about the amount of miles I have Noticed those that dont get a cooling flush during oil cooler replacement will see the oil cooler plug again

So lets Hope a Sensor or sensor wiring

Could also be Water Pump and or front cover cavitation creating flow issue

 

I checked the temps after a cold soak and they were within 2.5 degrees of each other, but were 20 degrees over the ambient temps.

If it was a flow issue, wouldn't that cause the coolant temps to get hot (over 188 degrees)?

Could this be caused my the oil being over filled?

 

You can also check trans temp which should be close cold. I found it took more like 18 - 24 hours in mild weather for the temps to get close to each other.

But... what's this about making oil? When did that start? who does your OCs and when last and when did you 1st see the oil level go up? It's not milky I assume or you'd have a whole different thread going. Or maybe you do now.

 

It's not making oil. I over filled it a little and didn't drain it back down.

As for trans temp, I don't think I have a gauge for that with the manual trans.

 

Not Sounding good sensors Look OK



One woould think
But with the small passages in the cooler it takes a decent amout of pressure to push coolant threw to take the heat away from oil

 

Is there any way to test if the water pump is not working as it should?

 

IDK of any Cooling System flow tests

If you still Have the Old Oil Cooler cut it Open However if your deltas droped after the Oil Cooler was changed and the New One brought the spread Closer together ODDS Are it was Pluged

I have seen a Few folks that the ECT vs EOT Spreads were High they go ahead and Change Oil Cooler and Find that the ECT vs EOT Spreads were STILL HIGH and Did NOT Change or very little if it did. At this point its usualy been determined a Flow issue


So all that said^^^ How Well did you flush Did you FLUSH

Did you go to Town and do a THURO Job [remove thermostat,pull block drains,run a garden hose and reverse flush and so on????] I probably went overboard whenI flushed I did it 3 separate times running a coolant filter inbetween flushes and went 1k between flushes. I bet I had 50+ cycles of fill--run--dump with Cleaners and water. All I knew at that time was I wanted to avoid repeat OC Failures from junk in there!!


And seems to have paid off Im close to where your at Milage wise around 20K since I put a Oil Cooler in mine But my Temps are SAME as the day I put the Oil Cooler in New!!!

Iv read about guys that flushed so Much the Water Bill about Doubled that month they did it LOL



Or was it dump coolant and do a few Water FLushes then Change the Oil Cooler?????

 

I flushed it a bunch of times, but i did not remove the T-Stat, I just drove it untill hot (I know realize how easy it is to remove the T-Stat even if i Have to unbolt a fuel line) and I did not do any reverse flushes. After changing my oil cooler last time my deltas were great, even towing heavy in the mountians (Vermont). Now recently after my truck burped up some coolant (determined to be a faulty cap and overfilled coolant) I have been noticing a rise in deltas to what I have now.

when you say you went 1K between flushes did you put coolant back in or run just water?

 

at least it will be easier because I dont have to remove the starter because of my fumuto drain valves......lol

 

Well it DID NOT get Flushed Properly!!

Leaving the thermostat IN is the worst thing Folks do when its known the OC is Plugged

{If the Oil Cooler spread is OK Folks are Fine to leave thermostat In and just do some simple water Rinse basicaly}

Even if driven till Warm ECT190* the thermostat is Only cracked open at this point NOT Much Flow and that how cleaners work HIGH Flow

The thermostat needs pull to do a couple things
#1=Create HIGH FLOW
#2=Create TURBULANCE

High flow and Turbulance is what breaks the junk Loose during the Flush

Pull Block Drains

Pull Lower Radiator hose off

I took apart every Cooling system Hose connection and with Block drains Open I stuffed a Garden Hose in each spot.

So when you stuff Hose in at the thermostat Housing this reverse flushes the Engine/Block.

I tied my coolant filter Return line in at the Heater Return Line Since I could take apart at this Location I stuffed a Hose in there and reverse flushed the Heater Core by itself with High flow Hose

I did not cut any corners and had 3 days into flushing by the time I changed the Oil Cooler

You MAY get away with Reverse Flush of Oil Cooler and system IDK

SOME GREAT IDEAS ON OIL COOLER BACKFLUSH
https://www.ford-trucks.com/forums/1...ch-advice.html


IMO Reverse flush of the Oil Cooler isnt the Best the Passages are so small that some will never get cleaned out.

But reverse flush has worked for some especialy those that have newer oil cooler



DEFINATLY PUT COOLANT BACK IN

These trucks will literaly Rust/cavitate overnight with water only in it

The first time I put New Gold coolant back in after the flush

The next time I just filter the coolant and put back in and when I installed the new OC I put NEW ELC in

Iv had to drain my coolant several times for other things and Iv just been draining into a Clean container and filtering it good before I Pour it back in the truck

 

Once this crap is in, it seems to plug in every corner it can and finaly plug the cooler. I flushed and flushed for days but I think the most important is to back flush everything independently so the crap that is in the inlet just flushes out.

I did like Blade said, heater rad one way then reverse, removed thermostat and flush the block, I even put the hose up trough the block drain, big rad up and down.

Good luck.

 

Exactly^^ you cant go Overboard with it thats for Shure

I swear each time I took that Lower Hose off at Each Dump cycle I could see a Small amount of Brownish Junk come out right at first liqued to come out upon hose removal

I think by the end I wasnt even Tightening Hose clamps and leaving Block drains Loose so I could just pull apart and Dump n Refill fast many many times

I never did Reverse Flush the Oil Cooler Itself cause I knew I was changing it at the end of the flushing so I really was hoping that it could act as a Filter and catch the garbage throughout all this Flushing

Here is what it Caught



The Screwdriver Points to the Coolant rows Below