What causes head gasket failures?
Howdy everyone. Curiosity has struck me again and I am wondering what causes head gaskets to fail on these discovery 2's? Is it from running too hot, or overheating? I'm thinking of installing 2 16 inch auxiliary fans one in front of the radiator to cool it and blow air over the transmission and engine oil coolers and one on the back of the the condenser to act as a second puller in between that gap, to suck the heat out and help the a/c too! I'd have 2 independent thermostatic controllers I found for each fan! One probe would mount in the radiator hose on top and the other in the transmission cooler or condenser! 1 thermostat would set at 197 degrees fahrenheit and the other at 212 degrees fahrenheit overlapping set points for strenuous times, like towing my future travel trailer where one fan can't keep up with the heat! That and I'm buying my new upper hose assembly and 180 degree thermostat to keep my stuff cool along with a 70/30 coolant ratio! Is this a good plan? If my system works my over all system temperature sitting at mcdonalds with the A/C running, on a 115 degree day won't budge from 190-196 degrees! These fans are rated at 3000 CFM each! Including the factory condenser and mechanical fan I'll have four cooling fans to prevent catastrophic engine failure. Sound good folks?
Used a Ron Francis AR99 dual fan controller, but you could get away with putting both fans on at once. I like the Ron francis as the thermoelectric switch mounts to the back of the head on a bolt. I recommend you have them wired to your A/C switch to help out when the A/C is on.
I would rather have both fans fans mounted on the radiator one pushing and one pulling than one mounted on the A/C Condenser.
I had good success with the flex a lite 15” setup, and their electrics are kind of janky. The Ron Francis stuff is much better. The two 16” fans may be over kill, but $&@& it. You have the dough over do it.
If you are an Apple person then you have to do some research the software is different and you may need a different device on your port.
I have the fans out of an ‘05 GTO in mine. One 12” and one 14” fan that both pull. Got them from a yard online.
Used a Ron Francis AR99 dual fan controller, but you could get away with putting both fans on at once. I like the Ron francis as the thermoelectric switch mounts to the back of the head on a bolt. I recommend you have them wired to your A/C switch to help out when the A/C is on.
I would rather have both fans fans mounted on the radiator one pushing and one pulling than one mounted on the A/C Condenser.
I had good success with the flex a lite 15” setup, and their electrics are kind of janky. The Ron Francis stuff is much better. The two 16” fans may be over kill, but $&@& it. You have the dough over do it.
The main reasons these trucks overheat, is because for several years, Land Rover used Dex-cool in the engine, the oem head gaskets weren't really prepared for the stress at the corners, Land Rover designed a cooling system that uses pressure to open the thermostat, not just temperature.
Not kidding when I say that Land Rover designed the cooling system "for passenger comfort"
Now, for people that have the hg fail after replacement, I would chalk that up to people not torquing the head bolts down in order, continuing to use dexcool, not replacing the thermostat with an inline setup, and in-general many people don't check heater core O rings for leaking. Literally, almost every overheating thread here DOESN'T mention that.
If the hg job is done right, and the coolant level is maintained, and you check ALL possible leak areas, you probably won't have to do them a second time.
I like your fan idea. And to emphasize that everyone has slightly different coolant temps; I live in Austin, Tx and I sit in traffic a-lot. In traffic at 109 outside, my truck is doing 208. I have the inline thermostat mod.
And just to give Rover some credit; I've seen more Honda's develop warped heads over the years of normal use, and cause very slight and slow overheating issue. and those are all aluminum engines.
Not kidding when I say that Land Rover designed the cooling system "for passenger comfort"
Now, for people that have the hg fail after replacement, I would chalk that up to people not torquing the head bolts down in order, continuing to use dexcool, not replacing the thermostat with an inline setup, and in-general many people don't check heater core O rings for leaking. Literally, almost every overheating thread here DOESN'T mention that.
If the hg job is done right, and the coolant level is maintained, and you check ALL possible leak areas, you probably won't have to do them a second time.
I like your fan idea. And to emphasize that everyone has slightly different coolant temps; I live in Austin, Tx and I sit in traffic a-lot. In traffic at 109 outside, my truck is doing 208. I have the inline thermostat mod.
And just to give Rover some credit; I've seen more Honda's develop warped heads over the years of normal use, and cause very slight and slow overheating issue. and those are all aluminum engines.
Last edited by The_OGCJR; Jul 25, 2018 at 05:36 PM.
Why thank you! at 120 degrees yesterday my dads 2017 ford fusion hybrid was screaming! That and my sisters 04 hyundai sonata hated the heat too! ive gotta do a prestone flush and ill eventually add some water wetter to my 70/30 mix. i would go higher but in vegas here im afraid i might boil over by the time i hit 80/20 in coolant concentration!
I have used nothing but a 50/50 ratio. I don’t but premix usually, I usually just buy a gal of distilled water at grocery store and full strength Prestone or similar.
I have used redlines water wetter too, but that doesn’t seem to help me
I have used redlines water wetter too, but that doesn’t seem to help me
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akbrewer
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Aug 21, 2015 10:25 PM



