Head Gasket Series: Cool Runnings

Hot Head

I left the 4Runner in Brighton with Andy as he did not want to let me have it back without a decent Road Test; he wanted it to be 100%.. Good job too..

While driving the 4Runner, the Engine Temperature Gauge would sit happily at the midway, the Coolant being cooled sufficiently. However, when sat idling the Engine Temp would rise slowly but surely until rev’d beyond 1000RPM, thereafter the temperature lowering to an acceptable reading. It was a little puzzling.. After a phonecall and some discussion, it was decided that the introduction of the “upgraded” Aluminium 4 Core Radiator was to blame..

Fluid Dynamics

The 3VZE Engine holds approximately 9.5L [out of the Factory] of fluid in its Cooling System, but the introduction of the new Radiator upped this capacity to nearer 13L which put additional, and as it turns out untenable, pressure on the Water Pump to do its job; it simply couldn’t push that amount of Coolant around the System at idle / 750RPM.

Short of the introduction of an additional Water Pump such as a Davies Craig unit, a return to a Stock Specification Radiator was the only option.

The 3VZE Engine holds approximately 9.5L of fluid in its Cooling System, but the introduction of the new Radiator upped this capacity to nearer 13L..

Moto

I opted for a Mishimoto unit, which is a quality brand and an endorsed replacement for the 3VZE Radiator. Only trouble is, they tend to be manufactured on demand from Denmark, rather than held in stock, and since no UK Supplier had one, I tracked one down in stock at FR Sport in the US; moreover, it was in a Sale and they shipped Worldwide.

Topping off the Job, literally, is a 0.9 Bar Rad Cap [not supplied with the Radiator rather frustratingly] and with the requisite Litres of Red Coolant poured in and the System bled, the Job was [finally] done.

School of Experience

Lessons learned..? You betcha. And expensive ones too; but there’s an idiom about that, I’m sure.

Burbling back home through the Sussex & Kent Countryside, looking over the Steering Wheel, I found myself experiencing a sense of Pride. Pride that I had Top End rebuilt the V6 under that Bonnet, something I had never done before, something at great emotional expense [as well as financial, obviously].

Back Home, I treated the Beast to a Wash, and a through one. Since everything hidden was now working 100%, the Body was Solid, everything else was new or refreshed, it was time to turn my attention to the Cosmetic side of things: Paint and the Interior..