My recently installed ScanGaugeII is showing EOT - ECT difference of 40° to 55° at highway speeds. So it looks like another failing oil cooler. My ECT is around 175° at these speeds. So it looks like the thermostat is also bad.
The other day in 83° ambient temperature at about 70mph my ECT was ~175° and my EOT was ~225° and sometimes ~230°.
Yesterday evening in 65° ambient temperature at about 65mph my ECT was ~170° and my EOT was ~215° up to ~220°.

My immediate concern is what I can do now to avoid further complications. But I'm working a job 6.5hrs from home and I don't have adequate tools here to fix anything. My job requires me to drive as much as 160mi a day (no load, mostly highway). And Thursday I'm driving home for Easter.

I plan to stay home for a few days after Easter to do some work on the truck to make it better. But what can I do in the meantime to get by? I know it's not ideal, but am I ok with EOT at ~230° for this kind of driving till I can get home? And how hot is still within tolerance range? Is the faulty thermostat the blessing in disguise that it seems for now at 175°? I was told by one of the Innovative Diesel techs when I called the other day that I'm just as well off, if not better, to continue with my Aggressive Street tune so long as I'm driving conservatively. My truck definitely feels like it runs better with this tune, but would I be better off switching back to stock for now? I've been running my truck with the EGR valve wires unplugged for years. Is this the right thing to be doing now?

I changed my coolant, including VC-9 & Simple Green flushes, about a month ago the last time I was home. These flushes yeilded dark colored fluid with sandy looking and brown flakey looking stuff. After 48gal of distilled water, the fluid color gradually became almost clear I was still getting a little sandy looking and brown flakey looking stuff settling out. But I had to wrap it up and leave town for work again. I did not see any gel that I've heard about. I noticed a marked improvement in fuel mileage on the 6.5hr trip back here to work. I don't know if the oil cooler was already plugged or if this incomplete flush caused it, since I just got the SGII last week.

I plan to do another more thorough coolant change again with VC-9 when I get home. I read a post here at FTE about someone having success back flushing the oil cooler by removing the output hose and attaching a hose. If that works I'm willing to try it. I'm not really sure where the oil cooler is. I'm not experienced with working on diesels, but running a lawn maintenance business for 15yrs taught me to just jump in and turn a wrench myself. In other words, I have the aptitude, I just don't know the engine that well yet. So I could use some guidance.
I'm ordering the dieselsite coolant filter today and plan to install it while I'm home. I already have a thermostat at home, I just opted not to use it at that time because of the non-ideal results of the coolant change. I expected to have to do another coolant change soon anyway.

Is there anything I'm missing here? Are there other guages I should setup in my SGII to watch for? General comments/suggestions?

 

Make sure the fluid temps are nearly equal in the morning to make sure Scangauge II is reading right.

Here is a page on oil cooler location:

https://www.ford-trucks.com/forums/1...l#post10208768

Thread on back flushing oil cooler:

Replaced oil cooler still difference in temps - Page 38 - Ford Powerstroke Diesel Forum

 

Oh, and here is a link to a pictorial of a EGR delete and oil cooler replacement job:

Rob's truck build - New York Mustangs - Forums

 

Id like to see if anyone has had any luck backflushing the oil cooler

Im getting ready to change my oil cooler when I get it out Im going to see if I can flush just the old oil cooler

the post I read yesterday mentioned the oil cooler being just like a p-trap the coolant flows in the top port threw the oil cooler and then back out the top depositing any junk in the oil cooler slowly filling with sedement from the bottom up
seamed to make sense

everyone that leaves the thermistate in to get the vc-9 to temp basicaly is breaking all the junk loose and depositing it into the oil cooler theres not enough volume of water to get the junk back up out the TOP of the oil cooler

It needs the higher volume of water to keep the junk flowing threw it and to maybe break up whats in there already. Plus it still gets hot with the thermistate out

that post had a hose stuffed in where coolant continues on to the egr cooler you maybe even be able to dump a little cleaner in at that port and let it soak inside the oil cooler for a bit before you stick the hose to it and give it high pressure flush

 

I was thinking the same about running a cleaner in that way. Even using a hand pump of some sort and running Restore in a clean hot bucket of water and start the cleaning process from that point.

Maybe one day I'll try it.

 

I confirmed the temps are within a tenth of a degree before starting the engine and nearly the same just after.

When you guys talk about pouring in some 'cleaner' to presoak before a backflush, do you mean VC-9?

 

Some are leaning toward adding a flush with "Restore". From what I have been reading, "Restore" cleans out the goo found in quite a few oil coolers (coolant side). And "Restore+" is the same as VC-9. (I use the vc-9)

Here is a link to a thread showing cut away pictures of a clogged oil cooler. It's an interesting read.

Replaced oil cooler still difference in temps - Page 21 - Ford Powerstroke Diesel Forum


Now, your current temps and getting the truck home. That's a gamble.

 

nice pictures
thanks for the link amdriven

 

I seem to read a lot of these threads where somebody flushes their cooling system and a week or two later the oil cooler clogs and causes all sorts of trouble.

 

I'm kinda in the same boat.found out at a constant 70 mph I'm 27deg difference.I figure its been this way for atleast two years.I think you'll be okay as long as you keep any heavy loads off the engine until you fix it.I also found that at 60 mph it got within 20 deg. My temps were 175 ect, 202-203 eot at 70mph.at 60 mph it was 174 ect and 194 eot.I know my t- stats bad but I'm not changing it until I either do a flush or oil cooler.if it was at 190ect my oil temps would be pushing 230.its probably not something that happened " yesterday". You've probably been driving it like that for awhile now.

 

[quote=steelhead2;102.I know my t- stats bad but I'm not changing it until I either do a flush or oil cooler.

that how I look at it to
ya get a clogged oil cooler that wont cool the last thing ya want to do is slam it with more heat

mine almost seamed like it got to a point where it was so hot and the spread was so far apart that oil temps started to run away

 

That sounds all fine and dandy, but do you really want to play that game? When the oil cooler fails it can be really costly. That's the reason for watching really colse.

 

Definitely don't want to play that game.

 

Definitely don't want to play that game.

 

amdriven2liv,
Thanks for the links. Some good info there.
I've been reading a lot lately in the forums to learn how to diagnose and eventually fix problems with my truck.
The more I read I'm getting the sense that the majority of the problems with our 6.0L s can be traced back to the oil cooler, and I guess consequently the EGR(thanks again hippies/EPA, it wasn't enough to ruin the 2-cycle engine).

The link to the EGR delete was educating, inspiring, and maybe a little intimidating. What a project. Personal preference: I would have definitely used an IPA fluid in place of that Pilsner fluid though. I like my fluids Hoppy.
Wow that's a lot of stuff to remove to get to the oil cooler. Seems like ya should do other stuff while you're in there. No wonder I often see statements where others did: oil cooler and...
...EGR delete, head studs, etc.


Anyway what I gathered from reading those links is that I should at least do what I can to save my oil cooler, if for nothing else than to get by with it while I get my coolant system cleaned out with flushes and filter. No need putting a new oil cooler in only to have it clog again with the garbage still in the system. Plus it may buy me some time to learn more and to budget the funds for the new cooler or more inclusive upgrade/modification project.

And from the reading I gathered that Restore is alkaline whereas VC-9 is acidic. If it's ok to put Restore in our engines without adverse consequences, then maybe a base & acid approach would be a more thorough way to go, acid for the iron and base for the goo? I assume you'd want to do a bunch of distilled water flushes in between if ya took this approach.

I installed an exterior frostproof hot water faucet on the back of my house. I know it's tap water, but one of the few things good about Memphis is the water. Not only does it taste great straight from tap, it's low mineral. No we don't drink from the Mississippi River. I'm gonna have to flush a ton of distilled water through anyway, so the residual tap water would probably be less of a problem than leaving crap in the system.
BLADE35, I tend to agree, putting chemical cleaner directly in the 'out' of the oil cooler and trying that backflush method with hot water as a starting point might help? It seems like a clogged cooler would need at least some of the crap backflushed to allow a regular chemical cleaner flush to have effective access.

So maybe I should order some VC-9 and Restore?

I think I'll be leaving my 'bad' thermostat in until I can get a pure clean distilled water flush coming out.

As for my 6.5hr trip back home, I just have to. That's where all my tools are to work on my truck. And I miss my wife and my dog. And it'll be nice to visit my parents, sisters, nephews, & nieces on Easter. And hang out with my neighbors and friends. It's lonely here in this apartment in East Texas, where I don't have any friends or family around. BTW, I do not enjoy apartment living. Back home I'd have any of several friends I could call up and crash their garage for some beer and some 'fixin'. But I got nothing like that here.
So I'm headed back as soon as I can wrap a few things up here. Hopefully that's Thursday at the latest. It'd be nice to be home for Good Friday.

If I had a buddy here with some tools, I might try a quick backflush and maybe try to incorporate the Coolant Change 101 procedure with chemical cleaner on my way home with flushes about every hour. I wonder if that might help my EOT driving back home even without the advantage of backflushing first. If I could just get one plate level or channel to flow with chemical cleaner maybe the turbulence might start to clear out the adjacent plate levels or channels?