I'm new to the 6.0L. Bought my first one 2 months ago. Details in the signature. I bought it because it had an egr delete 18 months and a new oil cooler 9 months before I bought it. I noticed it had what looked like drops of exhaust soot in the coolant flow, but I didn't think anything about it. Got my gages about 2 weeks after purchase and noticed it was running a delta of 30 degrees (65 mph steady state). I would have loved to try and save the oil cooler, but I had to have the truck to tow the rv. So I pull the new oil cooler on it.

Before the new oil cooler I had to replace a busted radiator (I knew this when I purchased it). Mechanic flushed it (not with restore or vc-9, but with simply green degreaser). I didn't have gages to check the delta before the flush. After getting a new radiator and altenator, I notice the high deltas. At the time, I thought it was a good thing my coolant system was clean because I wouldn't have to worry about clogging up the new oil cooler. Looking back, the flush could have caused the high deltas.

After noticing the high deltas, I flushed it myselft because I wasn't convinced the mechanic did it correclty. It didn't change my deltas. I didn't use restore or vc-9 because I couldn't find it an I was in a hurry because I had to pull the rv the coming weekend. I got lots of crude out of system, but my detlas remained the same. This is when I decided to change the oil cooler.

Last weekend I finally got around to cutting my old oil cooler open, changing my first coolant filter, and BACK washing the heater core. Since that time, I've been on a mission to determine the best method to try and cleanse the coolant system.

Below is a picture of the coolant filter after the first change. I was amazed at the oily residue. These photos made it clear to me that the mechanic that changed the oil cooler did not flush the system at all. I call that stealing from the client. These photos are also after TWO coolant flushes. These things are $$(*)^%%%()* hard to get clean.


Coolant filter cut open with oily residue


Contents of coolant filter filtered showing oily residue

I proceeded to cut the oil cooler open and take a look. Sadly, rinsing off the metal debris after cutting with a sawsall removed any evidence of blockage. However, the photo belows shows how tortuouse a path the coolant has. The darker 1 mm slot is the coolant slot. I think its dark because my busted egr chamber was welded shut on both ends. THus, all the exhaust soot from the egr exhaust chamber got into the coolant flow.


Typical oil cooler cut-away showing the 1mm coolant passages.


Screwdriver inserted to the bottom of the coolant inlet. 1" of oily, gritty crude in the bottom of the oil cooler coolant inlet. I have a boroscope (wire camera) picture down the hole showing the same thing.

The second oil cooler picture above shows a 1" layer of oily, gritty debris in the bottom of the oil cooler coolant inlet. Once again, this proves no flush was attempted when the oil cooler ruptured. Guess where all that oil got caught. Yep, the debris in the bottom of the "p-trape" oil cooler caught it. I don't think any amount of backwashing could have gotten that out.

After seeing the contents of the coolant filter and the oil cooler, I start wandering what my heater core looks like. I then remember that after my second flush, the heater didn't heat real well. So, I proceed to backwash the heater core. The photo below show what the backwash looked like. Again, a dark goop floating on top. Not as oily as it looks, but it did appear to be lots of exhaust soot in it. I removed about 1.5 ounces of debris, but dropped the bucket upside down before getting a photo.


Contents of backwashed heater core.

Because both my coolant system flushes were executed before the oil cooler, and because my deltas are about 6 degrees, I'm confident the oil cooler is not this bad.

Flushing the heater core was easy. Disconnect the inlet on the passengers side. I did this before the heater control valve because it was easier to get my fat fingers in there. I wired the vacuum operated heater control valve open to allow the flow. I disconnected the heater return line from just below the degas bottle. My garden hose nozzle is the twist type that fit perfectly inside the heater core return line. I ran a garden hose from the heater core supply line to the 5 gallon bucket shown above and held the garden hose nozzle into the return line. I figured my grip wasn't strong enough to exceed the 16 psi pressure the heater core is exposed to often, so I wasn't concerned about pumping 60 psi from my house water system throught the core. I felt it was very successful.

Because this was very successful, and because I am told the heater core is about the same as the oil cooler, I thought why couldn't the oil cooler also be successfully backflushed. Consequently, I've done tons of reading on backwashing the oil cooler. Many thanks to those who've rigged up hot water flushes, and the like. They went through much trial and error to get us where we are today.

Seems the general consensus is once the oil cooler is clogged, backwashing can lower the deltas for only a few hundred miles, but then the cooler gets clogged again. This doesn't make sense to me, because if you can get the debris out of the system, how does it come back into the oil cooler. So I dug deeper.

I could have missed it, but everyone who has posted about backwashing the oil cooler did not appear to confirm the debris they removed was out of the coolant system. It seemed to be always washed into the engine block and assumed that the best we could hope for is blowing it out of the block drains. Well, the short term results suggest it is not getting blown out of the block drains.

If I understand the coolant flow path, there is a direct path from the water pump supply to the oil cooler. If the water pump could be removed, why couldn't you dump the oil cooler backwash contents out of this pipe without washing them back into the block? Then I came accross a very recent post that suggested the same thing. I don't think this member has posted his results yet. So, credit goes to the other poster for this thought, but I'm looking forward to seeing his results.

I talked to an old mechanic about this. He said any old mechanic will tell you you can never get all the debris out of a heater core, so there should be no expectation of getting ALL the debris out of the oil cooler. Well, we don't have to have it all removed. Just enough to lower our deltas, which has been done temporarily.

However, if you your oil cooler looked like mine with 1" of oily debris in the bottom of the inlet, then I have little hope you could get enough of that out to make a difference.

So, this post is to illustrate the importance of

1) If you are going to chemical flush, get a fumoto valve at least on the passenger side. Otherwise it will take two days.

2) If you are going to chemical flush, do it right or don't do it at all. At least use Restore.

3) Keep the coolant system as clean as possible. A coolant filter is a must have, not an upgrade. Just ask International. They run them on all their trucks. And change coolant every year or two.

4) Lobby for a law to make it legal to bodily harm any 6.0 mechanic that doesn't chemical flush the coolant system after an egr or oil cooler failure. You've got to get the oil and exhaust soot out of the system or it WILL do damage. I had to replace my oil cooler after only 9 months of service because the mechanic was negligent.

5) Someone needs to see if you can effectively BACKflush and oil cooler by removing the water pump and confirming that the debris washed out of the cooler gets removed from the coolant system.

Hope this helps someone. It shows how nasty the coolant can get after an egr or an oil cooler rupture. This is just my feeble attempt to pay back the tons of help I've received from this forum.

 

Good post Ryan. Thanks for the pics also. Ignoring the cooling system on a 6.0 is a very bad idea and potentially the start of ALOT of headache and expense.

I agree with all your points but I have to say I won't be trying to flush an oil cooler any time soon. I've read several threads by tenacious 6.0 owners flushing over n over again. If mine or any of my "adopted" trucks have any problems it will be a chemical flush and new cooler. I'm not at all interested in even trying.

 

Great Post Bryan and I agree with you. I picked up my 6.0 last month and this was one of my biggest projects. Getting the Cooling system in order. It takes some serious time and effort.

Here is a photo showing what the results of a straight water flush looks like, and then once the water coming out looks as clear as can be expected, I followed it up with a 2 Hour High Idle (1200 rpm) with 2 Quarts of Restore Cooling System Cleaner.

I started by draining all the coolant and replacing my block drains with fumoto valves. Then I filled the motor with water and ran it on a 200 mile trip and came home and drained it again. I did this for 3 days in a row. Final result was #9 in Red Below. Then I performed TSB 8-23-1 using Restore Cooling System Cleaner. Look at how much more junk Restore was able to clean!



Here is a Mirror image of the photo above so you can see the color difference between the FINAL 'Water only' Rinse (#9 in Red), compared to the FIRST Restore Drain (#1 in Green).

 

That's crazy.

Josh

 

99, were you the one that suggested backflushing the oil cooler with the water pump off? And didn't you have high deltas when you started? If so, what are they now?

 

No, that wasn't me. I haven't backflushed the oil cooler or the heater core yet. I had some issues come up with my house and I was in my crawlspace re-doing the plumbing, so I haven't gotten back to another flush of my cooling system. I am going to perform another flush using Restore just to see if it improves more.

It's hard to say how much my Temps changed (if any). I was seeing Temps of 10-15 (18 at it's highest) driving the same stretch of road from my house to work on a 100 mile trip. Unfortunately, during this time, I had a thermostat fail, and while my temps would get up to 198 at times, they would also drop to 180 or so. I can't remember what my temps were during the highest temp difference. Sucks, I wish I knew. When I replaced my thermostat, I was running about 10-12 degrees difference after a full water flush. After the Restore, I am running 7-10 degrees, so it's not looking like the Restore did very much, but as you can see from the color of the Gallon jugs, it definitely cleaned the system more thoroughly.

The good thing about it is that Restore is Excellent at removing Silicate Gel, Oil and Grease and Fuel and doesn't remove rust or scale, so I'm fairly confident I haven't knocked anything loose that will clog my oil cooler. At least that's my theory.

I want to do another Restore Flush and see if my temps improve. I plan on backflushing the heater core first, and then I might attempt a backflushing of the oil cooler. Fingers crossed. I'll post back.

 

You plan on backflushing the oil cooler into the block or pulling the water pump to clearly evacuate the oil cooler backwash? Very interested to see your results.

Because your deltas are normal, I don't expect much improvement from backwashing the oil cooler.

 

I have an 04 Excursion with a 6.0 and it has 108K on the odometer. I am starting to see temp spreads (I guess this is the "delta" everybody keeps talking about) of 12-18 degrees between coolant and oil. My normal range appears to be around 200 for the engine coolant and 215-218 for the oil, at highway speed of 70mph and road temps over 100. My plan is to install an EGR delete when the outside temps cool off, we are in the 100+ range right now. I am debating performing a oil cooler back flush, it sounds like it would make sense because we do it to other parts of the cooling system when they are dirty or clogged. I am planning the coolant system flush when I do the EGR delete. I am ordering a coolant filter this week and will install it hopefully after the weekend. I haven't seen the connections on the oil cooler so I am not sure if it can be accomplished with everything installed or if I must remove major components to perform the flush. I am expecting to remove some of the air intake components so I can gain access to the coolant lines but I am talking about components such as turbo, intake, waterpump, PS pump, those type of items.

Please keep us posted on your results and techniques so we might be able to duplicate them in the future.

Jeff

 

Thanks Bryan,and allways remember the last 3 to 4 flushes use Distilled water to flush out the Tap water, then 50/50 with distilled. dont leave just tap water it will rust in a hurry.

 

Bryan: Reps sent, very nice write-up. Who can you trust these days?! It sounds like you are getting there on the cooling side, and you'll have the peace of mind to know it's been done right...

Good job

 

Has anyone put a magnet to the "sludge"? Just questioning if a portion of the debris is magnetic? If so, wonder if placing magnets on the bottom of the radiator may minimize it making it to the oil cooler, like adding magnetic plugs on oil pans and tranny pans.

 

Would like some clarification here. The 6.0 Cooling Capacity is 28 quarts or 7 gallons. When you do a Drain of BOTH Driver's and Passenger side engine blocks and the radiator draincock, you get about 3.5 Gallons of fluid out. That's what I have been getting each time. This leaves you with 3.5 gallons of fluid in there. You would then refill with 3.5 gallons of undiluted ELC. NO 50/50 mix.

 

Correct, ELC plus the remaining distilled in the block gives the 50/50 mix.

 

The last 3 to 4 flushes. to Get the Tap water Out. then on filling the system I use ford gold with distilled, That being 50/50,1/2 gold 1/2 distilled for top off.

 

Jeff, I think you can remove the cover on the oil cooler to run the hose into the oil cooler coolant outlet to backwash it. I think you can also connect the hose to the egr cooler inlet to backwash the oil cooler. But that may require removing the turbo or something else more difficult than the oil cooler cover.

I think the only chance for long term success to clear the oil cooler is to backwash it with the water pump removed.