Please I Need Help From My Fellow QX4 Owners

[BoostMyQX4]

Can you check your QX4 after running it for a while and see if the bottom of the radiator in yours gets HOT like the top of the radiator.
I don't know if this is normal for the QX4, but mines the top of the radiator and top hose gets HOT but the bottom of the radiator and bottom hose stays cool to warm it doesn't get HOT at all like the top part of the radiator and hose.

Thanks and hopefully you can help me out here in figuring out if its a normal thing or not.

[CanuckQx4]

Yes its supposed to get HOT, cant touch it hot. The second the thermostat opens you can feel the lower hose get just as hot as the upper.

Your thermostat sounds like it failed. Assuming your letting the car warm/idle a while. In this cold weather it takes a while to get past 175 degrees

[BoostMyQX4]

Thats the thing, I took the SUV for a long drive to the outlets which is about an hour away from me and the temperature gauge stayed the same and when I reached the outlets I pop the hood touched the top part of the radiator and it was blazing HOT then reach under to touch the bottom part of the radiator and it was Cool.

[new2infinitiqx4]

hey i cant reply to a private messege case i am too new.. but ive never checked it before.. i will when i get a chance.. i dont drive it that much just to work and back.. and im in dressy clothes.. so i wouldnt go under the truck then .. but i will check.

[BoostMyQX4]

Im going to the auto parts to pick up a Thermostat hopefully that will be it.

[Towncivilian]

Inspect the radiator cap as well; follow NTB04-018 - RADIATOR CAP INSPECTION DURING COOLANT SYSTEM SERVICE. There seems to be some coolant residue around the radiator drain plug, you may want to change the O-ring for it next time you drain & fill the radiator.

Your brake fluid is black. When was the last time it was flushed?

Do you do your own oil changes? I see a Fram ExtraGuard installed, which has very lousy construction for what you pay for them. See this post for more details regarding oil filter construction and engine oil in general.

[BoostMyQX4]

Inspect the radiator cap as well; follow NTB04-018 - RADIATOR CAP INSPECTION DURING COOLANT SYSTEM SERVICE. There seems to be some coolant residue around the radiator drain plug, you may want to change the O-ring for it next time you drain & fill the radiator.
Yes i noticed that also before taking the picture, i thought it was some left over water from washing the car yesterday.

Your brake fluid is black. When was the last time it was flushed?
I checked the break fluid and its not that bad, it looks black but its actually clear.

Do you do your own oil changes?
Yes i try to do all my maintenance, we just bought the car at the beginning of February and havent really driven it around so i havent change the Oil nor the Oil filter.

I see a Fram ExtraGuard installed, which has very lousy construction for what you pay for them. See this post for more details regarding oil filter construction and engine oil in general.

Yes i saw this before and its what i will replace the oil filter with.

[Towncivilian]

Nonetheless, if you don't know when the brake fluid was last flushed, you should flush it. Brake fluid is hygroscopic, meaning it absorbs moisture from the atmosphere. This lowers the boiling point of the brake fluid, which can lead to brake fade.

[BoostMyQX4]

Nonetheless, if you don't know when the brake fluid was last flushed, you should flush it. Brake fluid is hygroscopic, meaning it absorbs moisture from the atmosphere. This lowers the boiling point of the brake fluid, which can lead to brake fade.

That i never done, i never done a brake fluid flush before, i don't even know where to begin

[BoostMyQX4]

Went to the Auto Parts store and picked up a timing belt kit, however when i ask for the thermostat gasket the guy pulled out a square looking one.
I told him to hold off on the thermostat because i needed to ask.
So i ask you, which is the right gasket for the front thermostat?
is it this one


this


or this one

[Towncivilian]

The bottom one might be the correct one, but the FSM says to apply liquid gasket to create the thermostat gasket. See LC-10 of the FSM.

[BoostMyQX4]

The bottom one might be the correct one, but the FSM says to apply liquid gasket to create the thermostat gasket. See LC-10 of the FSM.

Ok got it, sort of what i did with the Thermo Element unit to make a seal, i used RTV water pump and thermostat liquid gasket.


What about the Radiator drain plug, is it cheaper to buy the Oring or the whole plug instead?

[Towncivilian]

Might as well just replace both the plug and the O-ring, they both should be fairly cheap.

[NismoPick]

Sorry to bump a year old thread, but I'd like to know if Boost fixed this issue (I can't PM)... I have the same problem: hot upper rad hose, ice cold lower hose, temp gauge stays right in the middle after warm up.

[Slumpert]

The HOT top hose is a result of minor ebbing of coolant as the waterpump is circulating in closed loop due to the themostat being closed/pressure pushing coolant into the overflow tank. It is amazing the amount of cooling that these engines can accomplish without the radiator.

Figure 3 cut up might work but yea just use thin bead of RTV is what the manual calls for. The water outlet pipe on mine was badly corroded to the point I could not re-use it in peace.. I was able to buy a third party replacement for $15 at the auto parts store. Even though it is triangle shaped, the holes are not evenly spaced so you need to be sure the "marked" side is up. I messed up and had to redo the RTV when I tried to put it on rotated.

Once I replaced the waterpump, themostat, and radiator, both hoses get nice and roasty toasty when warmed up, and she has not overheated since..