Well popped the hood and checked my fluids noticed that my Degass bottle looked empty... So released the pressure and the coolant came up to just just below the recall sticker on the bottle... So added about 10-12oz put cover back on and started truck... Coolant again disappeared toward the rear of the degass bottle...Let it idle and checked again after 15 min... The coolant stayed well below the recall sticker..Shut it off went inside the house for about 15-20 minutes came back out checked coolant and now it appears to be a pinch over the the min mark on the bottle... So why does this happen

1)Why does the coolant bottle sometimes appear empty??
2)Why does the coolant almost disappear when you first start the truck??
3)Why does coolant level change.. From one startup to another(looks low one day next day looks good)

Any thoughts because I cant make reason out of it... I figure at least cold it should be in the same place every morning.. But it fluctuates

 

who changed coolant last time?

did you measure and log the amount added... and when.. etc.

 

The book says to check coolant with truck engine NOT running. AND you let it sit after shutting it off for 10-15 minutes. I don't worry about where it is while running. Fill to the MIN line while COOL and LEVEL! No mystery to me.

 

An improperly done coolant change can leave 1 gallon or more air in the system.

I had to fill mine up by that much before it "filled" from a not so good job.

 

I had the dealer do the vc9 flush about 6 month ago..Since then it puked a couple of times.. then dealer replaced fan clutch.. stopped puking... Took the truck up north -15*F decide to check thought it was a little low so added (didn't measure).. Started the truck went to get groceries checked it at store and coolant level was high just above min line in bottle... So drove home 300 miles truck puked.. Got home shut it off checked coolant and it was full to the top of the bottle.. came out 4hrs later and coolant was just above min on bottle(well above recall sticker)... Started it up and coolant dropped way down... did my gas test and came back good.. took to dealer and mechanic put a gauge on it and said everything was fine but it was over filled... Drove it for the last 4 days checked it today while running degas bottle looked empty.. shut it off went to just below the recall sticker... added 10-12oz and started it up again level dropped shut it off released pressure and went to middle of recall sticker(where it should be)... put cap on went inside came out a few hrs later and the coolant was up over the min on the bottle(thats about 1/2 inch more than ford recommends)...

Don't know when to add coolant ...coolant cold level low one day, coolant cold level normal the next....

 

You need to do this:

a) check for EGR cooler leak

b) test coolant for exhaust gas

c) verify degas cap is good --- probably by replacing it.

d) there is a chance you have a bad thermostat as well.

I wonder about the fan clutch...

Is there any signs of coolant leak anywhere?

YOu need to keep accurate records.


Read your bill.. how many hours were you charged to do VC-9 flush... and how much for the job?

 

Egr valve pulled was clean and dry... Did the combustion gas test and came back negative for gasses..Cap is the new updated one and thermostat is new both about a month old...

The fan clutch was replaced after it threw a code by dealer as for the VC9 flush.. it was done took them all day and they charged me close to $300.00

I don't think there is anything wrong just don't understand why the level fluctuates so much from one day to another.. I haven't added and coolant for almost 5 month and the truck ran fine.. Made the mistake of adding some up north first time I noticed it low.. I should have waited until the next day to verify that it was low....

Anyone else have this fluctuating coolant level

 

My view:

A fluctuation of 1" is normal.

The amount of fluctuation (if everything is as you say above done right) is NOT.

There had to be air in your system --- so it either was left in there when it was changed, OR.. sucked in because of insufficient coolant, OR - introduced there by an air leak when it is cold, OR - exhaust gases from EGR Cooler or Heads lifting.

Or, failed fan caused overheating.. and air somehow got in after coolant puked.

If you believe there is no combustion gases in it, and it is not trailing white smoke after it warms...

Then keep filling it... to min line... and watch it every 2 days, until it stabilizes, while logging the amount of coolant used.

Be sure you use pre-diluted coolant or dilute it properly.


Somewhere I did a calculation of the amount of flux caused by temp changes.. and on my degas, it was about 2"

 

Well I was wondering Could me changing the thermostat cause a air pocket??... I did pretty much empty the radiator.. Filled a clean 5 gallon bucket.. Then I just poured it back into the degas bottle.. Since then about a month or 2... All I have been driving is short trips maybe 3 - 4 miles a day..all city...

 

That would do it.

You almost certainly created an air pocket --- that is not to say there were not air already in there.

 

How do you go about burping the system on these 6.0... Thinking of flushing the antifreeze and replacing new...

 

See the coolant flush procedure that will get most air out.. but some will still remain.

 

I've been going through the same thing. Did a flush 2 months ago when I did the coolers, and I've been adding coolant ever since. Was starting to price out studs and head gaskets, and it quit using a couple of weeks ago, and has been stable ever since. Obviously air pockets. It will vary over an inch in the tank from when it's hot or cold.

 

John...

I had the same scare... and recorded how much I added.. until it stabilized.

Saved a lot of money by taking my time and just logging everything.