Preventative measures Re: over heating?

[Nipper]

I have seen many mods and advice re-prolonging the life of your 2.4 head/engine.

I have to drive mine 25 miles every day in normal traffic and occasionally tow a boat out of a lake at the weeekends.

I am just about to completely replace all head etc and want to make the job last! what would you recommend i do?

Is it worth running a larger bore exhaust? if so how/where can i get one?
What is the best coolant to use? where from?
i bought a replacement thermostat from a local auto parts place what temp should it be?
obviously all new filters.
Any other genuinely useful words of advice? I dont really fancy butchering the bonnet unless it really works.
And when should the fan on the rad kick in?

Thanks all
Nipper and the Spaniels

[marky]

I'd worry about all the mods later as you dont really need them, unless you have money burning a hole in your pocket.

[Koi]

If you are replacing the head with a genuine Toyota new one, then any problems shouldn't re-occur. It was a design fault, so a new head will sort the problem.
You can fit a 3" down pipe on the manifold then fit the 3.0 exhaust system right through, its a mod done in Aus quite a lot, helps release gases easier. I wouldn't go to big as if theres no back pressure the turbo etc won't work effeiciently.

[Elvz]

Take your radiator to a specialist and have it pressure tested and if there's the slightest doubt about it's condition replace it. Replace all the rubber hoses including the small ones and all the hose clips - up to you what type you use but the smaller OEM ones are not reuseable.

I use either Toyota Long Life Red coolant (Stock number 31762 30927 463) or the Mercedes equivalent but the brand isn't as important as following the instructions.

The correct thermostat is Toyota Part 16401 5B440 which opens at 82˚C but the 88˚C version is probably just as good in the UK.

When its all back together, check that the cooling system is full and has no air locks and that it doesn't leak. Also check that the viscous fan cuts in quite early - you should be able to hear it. After that its all down to how you maintain and drive it.