Temp Guage (308)

The type of instrument that red mentions is most valuable, all radiator shops SHOULD have one. You can see if each and every tube in the radiator is getting hot etc and anyone with a clue on what they are doing should be able to pick up where the problem is, without costing you a cent in changing components etc.
I did get one from Dick Smith, it worked well on things were that of high temp, but didnt work well on anything that was lower than ambient(shiny,dry or black whatever - asked and got my money back, wanted to be able to use it on aircon systems too.

The engine was indeed actually getting 'that' hot (water would evapourate off instantanously if it touched the block, and believe me, you didnt want to touch it)

I ended up putting a new thermostat in, didn't help.
So I took the old thermostat, ripped it's guts out + cut the metal so only the metal circle was left (i.e. essentially no thermostat, but still a bottlenecked flow as opposed to nothing there at all).

She now runs at about 1/2 temp, as far as 'warming' up to get oil flowing properly etc. It seems to be fine to me, doesn't take very long with a stationary idle-warmup before driving.

This little experiment leads me to believe it's possible that the pump, while working, doesn't do a quality job.

Later on, particularly as ambient temps get cooler, will install new pump/this new thermostat I have sitting here.

For now, everything seems ok, would rather wait an extra minute or two warming up the engine than having one that runs far too hot.

Your temp(cylinder head), should be hotter than the water temp when there is water flowing, that is why I asked what happens to a drop of water when it hits the top tank, though it does sound like it is all too hot.
Didnt really understand your reasoning for why the water pump is not doing a good job? Engines that overheat, all warm up quickly, regardless of their coolingfault. If you gave us some answers to previous questions, that would help.
Re warming up: unless you are doing full throtte racing, you are not going to create any less wear sitting there idling as opposed to, gentle driving till engine is at operating temp, is going to be easier on your hip pocket and the environment

Hrm, reason I suggested it is there is only three possibilities I can think of currently:

a) Fan [it's one of those sharp blade ones] isn't drawing enough air through the radiator at idle.

Water pump isn't pushing water through quick enough
c) Water pump is pushing water through too fast.

Essentially, by ripping the guts of the thermostat out, my temp sits at 3/8th on the freeway, about 1/2 suburbia driving, and in the heart of the city (stop/start with no speed for airflow) she can/will hit 3/4 and sometimes a little over.

Driving me crazy at the moment still trying to work it out (but it's pointing towards airflow/water circulation).

It's at least running a little cooler than before when moving.

a) Fan [it's one of those sharp blade ones] isn't drawing enough air through the radiator at idle.
Water pump isn't pushing water through quick enough
c) Water pump is pushing water through too fast.

More info on your fan, is it engine(fixed or clutch)no. blades - or electric(how powerful)?
How hot does the ambient have to be till it lifts off thermostat temp?
If you measure the temp of the tubes at the bottom of the rad and compare with the top, you will have your answer. If only a degree or so temp difference - not enough airflow or radiator, 10deg or more - not enough coolant flow.
Option C, is not valid, the faster the flow the better, though any more than 80L per minute in a v8 will not achieve any noticeable further benefit to the cooling.

Edited by devilsadvocate, 29 January 2006 - 01:22 PM.

Ok, I thought water pumping through the radiator too fast would not allow sufficient cooling (even though, theoretically it would come back around faster).

It's 4 sharp blades [with the dodgy rivets holding blades on], it's a fixed standard fan running off alternator belt.
Belt is not slipping (at least not squeeling).

Only seems to have these temperature issues in very heavy traffic driving.
Otherwise, I'm quite happy where it sits (3/8th freeway and 1/2 normal suburbia stop/start at 60kph).

Ambient temperature doesn't seem to effect it very much.
Middle of the day or cooler night-times, still behaves the same.

Keeping in mind, it seems that only after removing the guts of the thermostat I was able to achieve 3/8th and 1/2 temp, which would have allowed for slightly less restricted waterflow over a fully open thermostat.

An upgrade of your fan wouldnt hurt , though the four bladed fan was considered/proved fine for a stock v8. If it is getting warm, while driving around at 60kmh you dont really want to be having to constantly use electric fans(they would need to be powerful to make any difference at 60kmh anyway), then a clutch fan would be more suitable to bring the temp down, as well as being an economical and easy upgrade. More airflow will always improve things(unless the rad is totally clogged), though it may be that the circulation is the major problem, you really have to test for that as suggested. How does the temp end up if you run it at 3000rpm while stationary?

Edited by devilsadvocate, 29 January 2006 - 01:47 PM.

Not sure mate, I will give it a try tomorrow when the noise will be at a little more acceptable hour.
Had my hands full with other things today.

Appreciating the advice so far

for a stock v8

Not entirely sure what a huge difference it would make to heat generation, but she's not stock entirely..
Only things I have confirmed for myself was that it is definately bored 60 thou over.
And the owner of the block previously said it was ported/polished (enlarged ports?) and larger valves?

It could be entirely possible, a clubsport 304 v8 couldn't keep up with the old Torana *Shrugs*

Edited by Loki, 29 January 2006 - 07:28 PM.