04 Excursion psd, bought with 59k in june at ford dealer, now has 69k, I decided to do a coolant flush to see what was in my coolant and etc. Drained what was in there, replaced with distilled water, drove 250 miles home, drained. What came out was a light yellow color. Refilled with distilled water, drove to town and back, engine at normal operating temperature, ran heater and etc, and drained again. What came out was a little bit lighter yellow, as expected. Refilled with distilled water and pulled a trailer with 3000 lbs of gravel just a few miles down the road at a very low speed and back and then drove into town and back again. Did NOT run heater this time (just forgot). Drained. What came out is a very dark yellow almost brownish color. I refilled with distilled and drove the truck into town and back again, it was good and hot and I ran the heater the whole way, and I just drained it and its the same color as last time, no lighter.

This appears to be against logic and is in conflict with other people's pictures of their coolant flushes. Any ideas why this is happening?

 

The only thing I can think of is that the first two times I drained the coolant, the truck had sat long enough that the thermostat may have already been closed.

 

You may need to do a good backflushing. Then do the distilled flushes. I backflushed for probably 2 hours, trying to isolate each component. Then I did 5 distilled flushes before it cleared-up.

 

that still doesn't explain why it would get darker on 3rd and 4th flush. I would like to do a backflush but I can't right now.

 

My coolant looks pretty much like that pictured in this thread, though I think its a little less rust colored. I will try to take pics when it is light out:
https://www.ford-trucks.com/forums/9...-flushing.html

 

You did not say if you went back with any coolant or are you going to do a real flush or what if it has distilled water in it now it will look like rust because it is going to rust. Need ELC coolant
pop

 

The logic is that you have loosened up some kind of sediment in your truck and the new water and the "towing" is getting the motor hot and loosening up stuff.

Just doing a coolant flush is good... but sediment settles in the low parts of the motor and radiator and only moves around when "under pressure". This is why so many of us use an aftermarket coolant filter in addition to "rooutine coolant flushes".

I would keep flushing with distilled water and make sure your temp-gauge always go to "normal" during each driving session. I use 20 gallons to flush my system every 50,000 - 60,000 miles (only takes 18 or so with some left over to top off the system).

Forget logic and just know that if the color of the water/coolant coming out after 4 flushes or so is not pure water... then you have alot of build-up somewhere and you have to keep going.

After system is running clear... drop lower radiator hose one last time... add the appropiate amount of straight coolant into degas bottle to equal 50% of your total cooling capacity.

Run motor at idle and add just distilled water to top off.... you now have a perfect 50/50 mix of coolant in your system. Drive a few times and let it cool to get rid of any air in the system... and just top off with water only.

Good luck,

 

There is no way to approximate since no one seems to know the total volume of the excursion's cooling system with the rear heater and all. I will have to obtain some test strips and try to use those to get the proper concentrating of antifreeze. I should be able to get close ball park.

 

I'm familiar with the procedure, I can't afford a coolant filter right now but plan on buying one when I can, though it seems pretty pointless since plenty of members have installed them and still had failed coolers. You say that sediment only moves "under pressure" but this isn't true at all... if it moved under pressure it would move every time the engine achieved normal operating temperature, as the cooling system is pressurized.
If there is indeed sediment settled at the bottom of the motor, then there is no practical way to dislodge it, as even a 'back flush' would not flow water over those areas at the bottom of the motor. I feel like putting tap water into the cooling system is a huge step backwards anyway and I don't plan on doing that. Tap water around here is very hard... I wouldn't want to get any of it into my cooling system. So for now doing a regular flush with restore and distilled water is the best I can get.

 

First off... I never proposed to do a "back-flush" and have never done so on my truck (now with 199,500 miles on it).

Sediment moves and collects in the low areas of the motor and cooling system.... it will move around, but when you drain & refill, there is no pressure to move the sediment out of your motor (it just stays where ever it happens to be).

I use the dieselsite.com coolant filter system... and BTW, the pictures shown in the 6.0L section are mine that I sent to them several years back. Even after several drain and refills and such... even to this day, my filter still filters out sediment and loose sand particles (from when the motor was casted).

It is the casting sand that has clogged up many EGR coolers and the like. As well, cooling systems that are not regulary serviced will have particulate drop-out... which then looks like white/calcium deposits. This is why I choose to flush my system every 50,000 - 60,000 miles and use a coolant filter... and not believe that Ford thinks that their coolant can go 100,000 miles (factory fill that is). They have since revised their cooling system service intervals and test procedures (sure glad I do it every 50,000 miles and never worry about it).

On a final note, the rear heat & AC unit does not have coolant running to it (just the AC-Freon). Heat is provided by a electric heating element... if you look under your truck there are no coolant lines nor are there any hidden ones.

I agree with you on not using tap water... but maybe you may consider using it to really flush the motor clean, then re-flush with distilled water to finish it off??

Have you considered using the Motorcraft VC-9 cooling system cleaner during the flush process... then re-flush with distilled water to remove all traces of the VC-9?

Good luck,

 

Ive been told that YOU CANNOT Backflush unless you have a way to Regulate Water Pressure Going into motor... How is everyone else regulating your water Pressure (15psi max as cap is 16psi)... Dont want to hook up and flush with tap water and blow something out without knowing it!!!!!!!!!!!!!!!!!!!!

 

Flushing with distilled (or tap) water is needed to remove old coolant and other debris. If you keep running with plain water, the system will start to corrode and the coolant (plain water) will turn either reddish (rust) or black (iron oxide) colored.

These trucks require a corrosion inhibitor for normal operation. Anti-freeze provided that corrosion inhibitor. Plain water has no such capability.

Recommend finishing your flushing and adding the anti-freeze of your choice. I use the Ford yellow stuff with good results. The ELC coolants may be better. Either will work.

Lou Braun

 

I installed fumoto valve in both of the block drains and ran tubing down to a point where I could collect the water. I used restor first and it took approx. 35 flushes to get clean water out. Then I used restore plus and I flushed at least fifty times and could not get clear water out (thermostat removed, heater on). Would pull radiator drain and bottom hose and drain both side of the block every time. Even stuck the hose in the degas bottle and ran the engine with the hose on full blast alternating between both block drains still no clear water. So did my head job anyway and replaced heater core, had radiator rodded and it was approx. 30* plugged, oil cooler and all hoses. After starting truck flushed approx 50 more times and finally got clear water out. I spent many hours flushing did not think I would ever get clear water out. You just have to keep flushing and to the best of my knowledge there is nothing you can blow out back flushing with a hose imho.

 

15 psi is what the system is designed to run at for max efficiency, doesn't mean it can't handle more pressure. Also your also back flushing with the cap off so you're not really pressurizing the system.

I back flushed with very hot tap water and I believe my water pressure is about 70 psi. No problems, in fact after back flushing my oil cooler my delta dropped from 30* to 10*. It's around 14* now after a week of driving and I will continue to drive it until it runs up a bit higher. Letting the old oil cooler filter out the crap before I install my new cooler and egr delete.

 

[quote=U.P. Builder;10897736]15 psi is what the system is designed to run at for max efficiency, doesn't mean it can't handle more pressure. Also your also back flushing with the cap off so you're not really pressurizing the system.

In 6.0 tech folder regarding back-flushing through oil cooler, it suggests to regulate water Pressure.. this is why I ask. If pressure is no issue then such info may/should be removed as to make flushing easier.. That is the only reason i have put off flushing my system....

7.0 Optional Reverse Flushing
Some cooling systems may require additional procedures to remove more contaminates
than a flush ‘n’ fill can perform. Additionally it is thought that the inclusion of a chemical
flush may dislodge particles which may become trapped in other parts of the cooling
system such as the heater core, radiator and / or oil cooler.
CAUTION: Your cooling system is equipped with a 16psi cap designed to release
pressure in excess of 16psi. Using excessive pressure in your cooling system may cause
damage. If there appears to be excessive blockage where you are flushing, you should
stop the reverse flush and determine and repair the blockage so damage does not occur.
A steady stream of water with little restriction is unlikely to cause issue however

Take right from the 6.0 tech folder.... Thx