by Lorne Goldman

Throughout its long history, many Plus 8s have been afflicted with cooling issues. There are many reasons for this and none include the coolant used now. Aluminum engines require alumium friendly coolant. In the early days, aluminum blocks were rare and often (infamously so with the Buick 215 era of this engine) this was not understood. Coolants incompatible with aluminum were used and this destroyed the head gaskets with consequent problems and a bad reputation for the motor.

However, pretty much all coolants are alloy compatible now. Check the label just in case.

Land Rover used to sell a coolant the had specifically for this block called Land Rover Summer Coolant. Nothing overly special about it save for the high price. And some auto shops or predatory companies will try to convince you they have a specific coolant answer for Land Rover...which is absolute nonsense. There are many coolants that will work well. That bbeing said there are also low qulity coolants. Curiously, REDLINE additive actually does work, though nowhere near the claims it makes. 

Personally, I go for a higher quality coolant..especially extended-life carboxylate-based coolants (except GM's Long Life) They were developed to be globally acceptable and provide superior performance over existing coolant technology. This technology is also known as organic additive technology (OATs). Because full carboxylate coolants have no silicates, they meet the stringent requirements of the Asian specifications, European coolant requirements because they have no phosphates and of course, North American demands. These coolants have international popularity due to having an unsurpassed corrosion protection for extended time intervals. It is worth noting that some people refer to them as “organic additive technology” (OAT) because the inhibitors which provide the corrosion protection are derived from carboxylic acids. In actuality, the protection is provided by neutralized carboxylic acids called carboxylates. This distinction is important because all coolants operate in the neutral or basic pH range (pH equal to or greater than 7). In fact, most coolants are made beginning with an acidic precursor, for example, conventional coolants based on phosphate start their lives as phosphoric acid.

Carboxylate inhibitors provide corrosion protection by chemically interacting with the metal surfaces where needed, not by universally laying down layers, which is the case with conventional and hybrid coolants. The implications of this functional difference are enormous: extended life cycles, unsurpassed hightemperature aluminum protection, as well as heat transfer advantages on both hot engine surfaces and heat-rejecting radiator tubes where heat transfer is critical to optimal performance. Highquality carboxylate-based coolants have demonstrated performance of more than 32,000 hours in stationary engine applications without being changed. One measure of true extended life performance is that at the end of a fleet test, the used coolant can be removed from the engine and still successfully pass tests designed for fresh coolants!

I have found my happiest result (so far) with a 50/50 solution of DISTILLED water (normally found at a large supermarket) and a respected OATs coolant and a bottle of Redline Water Wetter per engine (for an extra 2C drop).  

I also change my coolant every 20,000 miles and/, more importantly, I flush my engine and radiator every 2-3 years. (Detach the top rad hose, remove the thermostat and its housing. Remove the lower rad hose. Remove the two water cocks, one on each side of the block. Run water though the lower hose and continue to do so for 20 minutes or until the water runs clear. Now run water from the top of the rad entry for twenty minutes or until the water runs clear.


If you have Plus 8 heating problems, I strongly advise you to consult eMog.