Ford Powerstroke Diesel Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
I have high EOT / oil cooler question for you guys. I recently bought a 2008 F250 with the 6.4 from a local used car dealer, so I know nothing of the past history of it and how it was maintained. But I got it for a good deal and it's in good shape so I took a chance. I had a 6.0 for 10 years and did every repair under the sun myself, and unfortunately I am very familiar with the 6.0 and it's issues. As for the 6.4, a lot is familiar, some is new. My new 6.4 is EGR and DPF deleted with a base (low) tune to remove the delete/ECU parameters.

For the time being, I am monitoring my engine temps and such with my torque pro app until I decide which tuner and display I want to go with.

So I have a EOT issue, and know that theres a 95% chance it's a clogged oil cooler, but there are some fishy things about it that I want to try and describe, and maybe someone here has seen this issue and can point me to something else that might not be so obvious.

When my oil cooler on my 6.0 failed/clogged, it would give me like 20* delta after driving with a load in the summer, or pulling equipment, etc. Usually when you realize you have the issue. Now with my 6.4, my oil temps spike almost immediately after starting to drive. Sometimes they jump so quick, I think that there is no way it has enough time to get that hot so quick with no load and normal driving conditions. Like a 8-10 min drive.

My ECT always stays between 192-195. EOT starts at like 150s after a few mins, and as soon as it reaches the 195-200 range, it immediately starts climbing. 200-210-220 within just a few mins. If I drive for less than 10 mins it always stays below 225, which is still a 30* delta and I dont like that. I'm on pins and needles driving it. If I drive for longer than 10 mins, it jumps to 230s. And if it gets close to 240 I pull over and shut it down.

I know the culprit is probably the oil cooler, but it just seems odd to me how quickly it jumps in such a short time with no load. Almost like it's not actually the true temp.

I am planning to do a BPD remote oil cooler kit, either a full or a half. I dont want to do the full if I dont have to, unless I can confirm with 100% certainty that it is definitely a failed cooler, because that would require me to do a cab off removal. Which I dont have the time to or lift to do myself, and cant pay my local shop $4000 to do it. If I can can get by with buying a backflush adapter kit and doing a 1/2 remote kit (basically a supplemental cooler but the OEM cooler stays in place) and a coolant filter, this is what I want to do.

So what I have done so far. First thing I did was change oil with Motorcraft filter and motorcraft 15w40. Notice a lot of thick black sludge in oil filter housing. Cleaned out the best I could. Still no change in temps. So I did a coolant flush (not backflush). No change. Then I decided to change filter and oil again and try and clean the oil cooler bypass valve in the bottom of the filter housing. It was caked with sludge. This time I used Rotella T6 15w40 and HHS stiction eliminator. After cleaning the oil cooler bypass and changing oil again. Temps were normal for my first drive. I thought I had it fixed. Next drive, they shot back up. I changes EOT sensor just in case. No change.

So without jumping to the obvious (oil cooler restriction), and considering the almost immediate high temps with no load, and the temporary "fix " with cleaning the oil cooler bypass, something seems like I should see if anyone has seen this before. If I plan on keeping the truck for a while, I want to do the remote oil cooler , a true backflush with VC-9 and restore and coolant filter. But if I spend all that time and money to find out that it was a bad bypass valve or a restriction or reroute somewhere in the filter housing, I will be pissed. I need some ideas of what else I can do to keep driving without melting my engine if the temps are in fact "true". And possibly some small things I can do before jumping to spending $2000 and a weekend of work back flushing and doing a 1/2 remote kit. I dont think I can do the full kit myself, because I dont have a lift to pull the cab, and I dont want to pay a shop $4000 to do it.

On last note with the high EOT, I never get the green wrench light or the P012F code that has to do with EOT/ECT correlation.

What do you guys think? Sludge is stuck somewhere or preventing some flow to the cooler? Soemthing else causing it? Can EBP levels cause high EOT? If so, what is normal EBP readings. It has no EGR or DPF so I know I dont have a exhaust restriction. I'm leaning towards the oil cooler, but it was odd that I had a quick fix when I cleaned the bypass valve and change to Rotella T6, even just for a day. And also no codes or green wrench. What do you think?
 

·
Registered
Joined
·
1,242 Posts
I would say oil cooler. If you can see any debris in general, its already more than enough to clog a cooler. Usually the coolant side gets clogged though.
The delta correlation code wont come on until it is like 45-50 difference or something crazy like that if i remember correctly so it sounds like you shut it down or come off the gas before it gets to that point. The only other thing it could be is you are losing oil pressure/flow via a failing pump or a cracked pickup tube. However i have never seen or heard of either happening on a 6.4
 

·
Registered
Joined
·
868 Posts
Make sure you don’t have an airlock. Or blown hg or cracked head pushing air into the cooling system, although the highest point is the heater core. It could trap air inside that cooler. Causing you to have no cooling capabilities. Quick flush might pass coolant through, than the air came back. Just a thought.
Mines got a cracked head and I got air all over the system.


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
130 Posts
Definetly need a coolant filter as well to get all that a\sand from the casting out of the motor.
 
1 - 4 of 4 Posts
Top