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Range Rover still overheating after extensive work

1.9K views 7 replies 5 participants last post by  383vett  
#1 ·
We need some help. About 8 months ago, my RRS coolant outlet flange broke while I was driving. I did a bit of a hard acceleration and all of the sudden smoke started coming out the front. I pulled over and saw that it was just coolant leak and was able to make it the rest of the way back home. My dad is a mechanic so we ended up just replacing it ourselves. Anyways, after successfully replacing the coolant outlet flange, our car started overheating. To make it a long story short, after replacing a bunch of parts and doing a couple things to it, it’s still overheating. Here are the things we’ve done.

  • Replaced the water pump, once with an aftermarket and a 2nd time with OEM.
  • Replaced the thermostat
  • Replaced the coolant temperature sensor
  • Flushed the heater core
  • Tried bypassing the heater core
  • Replaced the coolant outlet pipe (we saw smoke coming from here too and common overheating problems related to this)
  • Replaced the oil cooler (shop recommended us to do this)
  • Tried vacuuming air out of the cooling system and replacing it with coolant
  • Tried burping the cooling system

A thing I’d like to mention is that every time we replace a part, we always vacuum fill it with coolant. 2/5 time that we’ve replaced a part and done this, we got heat back but it still eventually overheated.

Another thing I feel is important to mention is head gasket sealer. Before we replaced the first part on the car (coolant outlet flange), we waited about a month before we actually did anything. Every time we start the car up after that (for about 2-3 months to work on/test the car), there was always the light/medium smoke coming out of the exhaust. I’ve seen blown heads exhaust smoke but this didn’t look like it. Anyways my dad eventually decided to add head gasket sealant to it and it stopped.

  • We used a combustion checker and it stayed blue
  • We performed a leak down test and it indicated no leaks
All of this was done after the head gasket sealer.

At this point, we’re thinking it could just be the head but wanted to see what you guys think it could be.
 
#2 ·
Hey did you change the oil? Check the oil inspect it. Check the revisor and cap (coolant) are you having to add coolant ate you loosing coolant? What engine codes are reading? I just replaced water pump thermostat y-pipes front and rear coolant pipes getting knock sensor codes but no more overheating that gasket sealer could be blocking flow somewhere also is the fan engage
 
#4 ·
Rather than do the leak down test, do a compression check on each cylinder and compare. If they are all relatively the same, it's probably not the cylinder head. If you have one or a few that are noticeably low, you probably have a bad head or gasket. A leak down test is fine for determining where a leak is at, but I prefer the compression test, as I feel it gives a better idea of the health of the cylinder, mainly because with a leak down test you are basically only testing the cylinder statically at top dead center, whereas with the compression test, you are testing the cylinder in a dynamic condition and testing its ability to compress and pump air.
 
#5 ·
Using head gasket sealer in this motor is a death sentence in almost every case I've ever been aware of where it's been added (in the V8 or the V6 - guessing you have one?). ... Sorry to break the news.

I think you start pulling all cooling system omponents and checking for blockages.

I wish this information were out there -- DO NOT USE HEAD GASKET SEALER on a LR motor.
 
#7 ·
Because there is a possibility of passing the leakdown test, but failing the compression test. You could have damage at the bottom of the cylinder, yet it seals at the top, due to either a nasty taper to the bore or scoring at the bottom of the bore that doesnt exist at the top. But I'm not here to argue; both tests can be used, and I used to be like you and used leak down exclusively, but as I've gone on in years, I've found I prefer compression first, then use leak down to find out where. To each his own.