Hi again guys. This concerns the 2003 F250 i helped on the side of the road about 7 weeks ago. If you'll remember this was a lady and her daughter driving from TX to NC pulling two horses. She blew a head gasket doing 75 mph about 3 miles from my house in AL. After pulling to the side, she added a gallon of coolant. Upon trying to restart, the truck hydrolocked. I asked about the chances of a bend rod.

Well, the truck runs great now with new HG and ARP studs. I offered to drive the truck and horse trailer from AL to NC over Thanksgiving because the truck owners live 45 minutes from my inlaws. So, I drove the truck back last night. Truck runs smooth and tons of power. The only problem is very high EOTs.

Ambient temps between 35 and 50. Unloaded the deltas at 25 degrees. ECT is 187, EOT is 212. I am running the test correctly (60 mph, flat terrain, after 30 minute warm up). Pulling the 5k trailer brings the ECT to 187 to 192. The EOT gets to 244.5 and the fan cuts on for a couple of minutes. After a couple of minutes the ECT goes from 192 to 187, and the EOT goes down to 243 and the fans turn off. It did this for 550 miles. The max EOT was around 248. I drove it 75 to 80 mph. The trailer really wasn't heavy enough to cause those high EOTs.

So, Delta of 25 without a trailer. Delta of 57 pulling a 5k trailer. Running Rotella T5 (15W-40 dino).

(I did blow a CAC tube off and had to stop and reconnect. Boy these things have no power without the turbo.)

Truck has new ARP studs, OEM HG, Sinister EGR delete, OEM oil cooler, OEM filters, IPR screen and water pump. About 9 months ago the truck got a new thermostat and coolant flush. It got a good coolant flush when the HGs were done because i know the mechanic that did it knows how important the flush is. So, the coolant system is clean.

There was a thread about 3 months ago with this same problem and it turned out to be some obscure issue. If someone can point me to that thread, I would greatly appreciate it. I've searched and can't find it.

The owners said she remembers the fans turning on often prior to blowing the head gaskets. So, this appears to be a separate issue from the HG issue .... unless high EOT actually cause the HG failure.

The potential problems include:

1. EOT sensor. That would be an easy solution and I hope that is the problem. I do not know what the eot reading is after a cold soak. However, while idling, the delta is below 10. So, although this is the first step, it may not be the problem. is there a way to double check the EOT?

2. Cavitation in the water pump housing. Wouldn't this also cause high ECTs?

3. Low LP Oil flow through the cooler. LPO pressure looks good from the dash needle and the HPOP system appears to be functioning great. How do you determine the oil flow through the oil cooler?

4. Poor coolant flow through the oil cooler. Again, why would this be a problem and how do you measure it?

Any hints would be greatly appreciated.

Again, thanks to the great help this forum offers the world of the 6.0. This forum really does make the world a better place.

 

I remember WOW this been a Few


Did the EOT Sensor Jump Around?

Not the EOT sensor then Yes Front Cover Water Pump

Probably Needs a Water Pump It Got Hot once and the Impaller Slipped on the SHaft

They need A Water pump with Metal Impellar on MetAL Shaft

 

Do you know If the truck was Coolant Flushed??


Lots of Shops Skipped this and Had repeat Issue But that Still Should take Time to Clog again

It Need a Coolant Filter on that Ride

Sounds Like a EGR Cooler let Go

the HG Couldd been OK Shops are playing this out to look like Majoir Drama

 

EOT sensor did not jump around. I would have loved to have seen that. I would think pig tail. The EOT was smooth.

IT got a new water pump with the HGs. I don't know if an inspection of the WP housing was done. I'll ask again, will that not also cause high ECTs?? This truck has great ECTs.

This HG was toast. You could see the coolant running out between the head and the block. Oil level was about 1 gallon high on the dip stick. Pulled the oil drain plug and water poured out. No question it had a blown HG. I verified personally it was hydrolocked. After draining the oil plug, it was hydrolocked with the added gallon of water (not coolant)

I know the mechanic flushed the coolant system. He wouldn't dream of not doing it. I actually saw what came out of the oil cooler. It was pretty clean compared to what Iv'e seen. Anyway, it takes time to reclog the cooler.

Blade, ALL 6.0s NEED COOLANT FILTERS!!!

 

The obscure issue a few months ago was the oil cooler bypass wasn't functioning correctly causing the oil to completely bypass the oil cooler no matter what.

Josh

 

Ahhhh. Thanks, Josh. Now I remember. But I don't remember the specifics about how they found the issue or even how the oil cooler bypss functions. I'll do a search on oil cooler bypass and find that thread.

 

Well, LOL I had to be blunt and rude to the guy to wake him up and pay attention.

Guys kept telling him to test the water pump pressure, replace the oil cooler, he needs to do this or needs to do that when Mustang_309 on like the first page mentioned the oil cooler bypass and it went ignored, then went ignored again a few pages later and it's like finally "Hey! It's the bypass, replace the cover and be done with it!"

So he did and it worked.

It wasn't that the other advice the guy was getting was wrong, but he was throwing money and parts at it and nothing was working and it was painfully obvious all along the oil cooler bypass was junk.

As in this truck's case. The ECT is perfect the EOT is not. The cooler is new and likely isn't going to be plugged enough to cause a 57 degree temp difference on it's maiden voyage.

Josh

 

I don't remember that thread

Hell I probably posted to It LOL

So the guy had Chit Holding it Open in the bottom of the Filter housing


That was a Great thought on that one and Not common at all and EZ to Check

 

Josh, is replacing the oil cooler cover the only way to fix it? And last, what causes it to malfunction? I assume the bypass valve is supposed to stay closed. What operating condition causes it to open (in other words why is it even the) and what causes it to stay open?

How do you test it before buying a new cover?

Yeah, I know. Tons of questions, but what better place to ask.

Can't thank you enough for your knowledge, time, and pacience.

 

LOL Yes ya Got me


I couldn't remember the shop part

Folks come here and seems Like 3 Bad SHOPS to 1 GOOD Shop if you know what I mean

I certainly don't keep Track

 

https://www.ford-trucks.com/forums/1...r-repairs.html



Here ya go

 

Thanks Justin^^sent ya a Rep wouldn't let me post a Comment though IDK Why



Wow he spent lots of money chasing that

Its the First one I saw that was the Issue

But thinking Back I bet a Couple other trucks came thru with that Potentially the Same Problem as Well they ALL went down the same road Water Pumps and Front Coveres etc.............

looks like they never found Why it was Jacked up but the new Filter Base Fixed it

I wonder if it had a Piece of Chit in it that was Lodged that fell out when they took the Filter base out???? Guess will never Know but its Not Complex Valve from what I see and I never really looked at it when out

I saw Josh post about Salt in the Wound and ROFLMAO

 

he replaced this piece

Oil Filter Adapter assembly

 

Thanks, Justin. That was the thread I was looking for. How did you find it?

It sure would be nice to be able to replace the valve without having to replace the whole oil filter base.

 

I do not believe that bypass piece is replaceable by itself.

It is removeable so it shouldn't be too hard to inspect.

Josh