Proper coolant flush
6.0L Coolant Flush Procedure
With The Addition of VC-9 Engine Cooling System Iron Cleaner and
Thermostat Removal Option
1) Buy Four (4) gallons of Ford Premium Gold Coolant (or Zerex G05), Two (2)
bottles of VC-9 and one (1) Thermostat O-ring (if removing T-stat) at dealer.
2) Buy 15-18 gallons of DISTILLER WATER at local grocery store.
3) Open Radiator Stopcock and/or Drop lower radiator hose until radiator is empty.
4) Close stopcock and/or reconnect hose.
5) Add 2 bottles of VC-9 to degas bottle (The VC-9 is in the Ford procedure for
flushing prior to water flush and new coolant). Add distilled water until the degas
bottle is at MIN. Go for a 20 to 30 mile drive (Some say you need to drive at temp
for 1 hour to fully clean system). Drain system, then proceed either with or without
Thermostat.
Thermostat Removal Option:
A) Pull air cleaner assembly.
B) Drain coolant (See step 3 above).
C) Remove upper radiator hose.
D) Remove 2 nuts on t-stat housing.
E) Lift and move press sensor bracket to the side. Not a lot of play in it but it will
move.
F) Remove 2 more nuts on t-stat housing.
G) Remove housing. It will lift right off of the studs.
H) Reverse procedure to re-install. Use a new O ring (5 bucks at dealer). I used
Vaseline to hold the O ring in place. Tighten nuts to 23Nm (17lb/ft).
6) Add distilled water to degas bottle until it reads MIN.
7) Drive vehicle with heater on HIGH (HOT) until temp gauge goes to normal and
thermostat opens (Excursion owners Do Not Forget Rear Heater). If thermostat is
removed just idle for 5 minutes gently varying idle rpm’s between 750 and 1500 or
turn High Idle Mod on.
8) Repeat steps #3,#4, #6 and #7 no less than 4 or 5 times until drain water is
clear.
9) You now have 100% distilled water in your system.
10) Drop lower hose 1 last time, drain and reconnect. Reinstall Thermostat if
removed earlier.
11) Look in manual to verify your system capacity (27.5 quarts) and add 3½ gallons
of FULL STRENGTH Ford Premium Gold (or Zerex G05) coolant into your degas
bottle.
12) Start motor and add distilled water to bring system level to not exceed
the MIN Mark on degas bottle. PLEASE NOTE THE MIN LEVEL ON THE DEGAS
BOTTLE IS NOW THE NEW FULL LEVEL.
13) Drive truck around to open thermostat and let cool once or twice to purge any
air. May need to add more distilled water (don't add more coolant)... but when
done you have flushed your entire system and have a perfect 50/50% concentration
of coolant and distilled water.
Memo/Note:
The VC-9 is in the Ford procedure for flushing prior to water flush and new coolant.
Local 6.0 tech says they do use the VC-9 and then flush with water. If there was an
oil cooler leak then after the VC-9 flush they then flush with Simple Green or
Cascade, or vice/versa, also recommended by Ford.
You might note that if you have pulled the t-stat you do not have to take it out for a
drive during the flushes. Just run it for 5 minutes at about 1100 rpm's, hi idle mod
rpms, and drain. You do not have a t-stat to open up and have full flow immediately.
This will save taking it off of the jack stands if you have the truck jacked up.
VC-9 is not an additive! It is an iron cleaner that you run at temp for 20 or 30 miles
and then flush out. It is recommended by Ford. Some here don't use it I did. Your
choice as to what you feel comfortable with. Tech at one of our local dealers said
that he does use it so I did. 52 bucks is worth peace of mind to me. I changed mine
on the time limit of 5 years. That equates to 10 bucks per year. I think I can afford
that.
Also, on the heater, all you really need to do is make sure the valve opens. For
trucks without EATC, just put the dial on defrost, fan on low. Look to see that the
valve is open and you will be good. You could also just pull and plug the vacuum line
on the valve, and open it manually.
I am in the process of doing this way right now and on my 05 it is impossible to
remove the thermostat housing bracket due to one of the hard metal fuel lines are
right over the bolt to remove the back bracket. You will have to remove the fuel line
from the fuel filter housing to achieve this method, at least thats the way it is on my
05. So, the thermostat is not the easiest way to go about this with quite a few things
haven to be removed. My thoughts so far...... FAIL.
Wrong, after you remove the two nuts holding that bracket take a screw driver or
appropriate tool and pry it up and over. There is enough play to do it. I have done it
a couple of times with no damage to anything. Just don't act like a gorilla when
doing it.
Thats what I am saying, I cant even get to the back nut on the bracket to get to the
other two nuts. There is no way unless youre looking to do damage to the metal fuel
line. Obviously, you did it and you have some play with the metal fuel line. I did
not......
I looked at my 05' F250 and the thermostat housing didn't look all that bad to
remove, in fact I could do it with a bit of muscle power without moving or removing
anything else. Now comes the hard part. I have the thermostat housing in my hands,
and for the life of me I can't figure how to remove the thermostat short of a
blowtorch or reciprocating saw.
Put housing in vice and push down and turn t-stat bar to remove. Reverse procedure
for install. Use a new O ring. I used vaseline to hold it in place.
The t-stat will turn either direction to come out.