Thread: Radiator replacement

how many extra cubes have you chucked at it... ID suggest that there might be an alternate cause, also what temps are you seeing, how and where are you measuring the temp?

Meccles, it doesn’t matter how many cubes you have.
A classic at 100 - 110 only needs a certain amount of power to push it through the air, whether that power is developed by a 3.5 litre V8 or a 4.5 litre V8.
The same power should equate to about the same heat rejection into the cooling system.
If the cooling system coped before, it should still cope now, unless something else has changed.
If my understanding is correct, you have only changed the engine, so is the block, cylinder heads, inlet manifold, thermostat, thermostat housing, timing cover, temperature sender and water pump all flowing correctly.
Ignition timing and/or fuel mixture could also affect running temperature.

Phil

I think its fuel mixture. Plugs look lean/hot. Am going to richen up jetting/metering rods. As you say nothing else has changed.
I flushed radiator as there was some dirt/debris in block after sitting for years. It all flows well. Thermostat is my original 80c unit and its working.
Temp gauge both water and oil are in original locations and my dakota digital units which react real quick and seem very accurate.
Around town water temp is 80 c oil temp 80c
I have a pwr 21 row oil cooler fitted.
On highway at 100 kmh you can watch water temp climb first to 90-95 c with oil temp then following on. Slow down and both temps drop real quick.
So - next step is fuel mixture.

Is the replacemnt engine's thermostat the same temperature as the original engine?

The radiator might need more than a flush. Assuming it has copper tanks, the tanks can be removed for a proper clean.

Originally Posted by Meccles

On highway at 100 kmh you can watch water temp climb first to 90-95 c with oil temp then following on. Slow down and both temps drop real quick.
So - next step is fuel mixture.

yes, thats what happens when you apply more power to shove a brick through the air faster. 95 deg is an acceptable upper normal operating temperature, if it keeps climbing then youve got more to worry about.

So long as the cooling system is holding pressure and your coolant is correct, let it run to 105 if you need to.