Hey guys
I have the mildly built 5.3 in a '98 Range Rover.
PRW high flow water pump
24" w x 21"h x 3" deep aluminum radiator. Both inlet and outlet are on passenger side, double pass design
Electric Taurus fan and shroud
Stock thermostat
Worse at higher rpm's, heats up more and quicker.
Any warm weather at all she's over 220 and the fan cant keep it cool. Worse with the ac on.
Turn the AC off, it will go back to@220-230 if you let off the throttle some.
AC condenser is 1" in front of radiator
With the temp gauge at 215, fan on, I shot the radiator and got 152 degrees at the top inlet, 141 at the bottom. So the rad is only pulling out 11 degrees of heat.
Steam lines hooked up. Have a header tank in the system, its on the 3/4" hose side of the heater core hoses, T'd into that hose.

I have some theories....
The water pump is pumping the water too much, meaning it isnt hanging out in the rad long enough
A restrictor may be needed on the thermostat side, so the coolant stays in the rad longer. Griffin suggested that after sending them some readings
The radiator isnt enough. If the coolant is just dropping from the top to the bottom. Cross flow better? I'd need to redo the intake, but it's doable.

It's the only thing stopping the rig being enjoyed more

I think that is all the pertinent information covered.
Many thanks in advance

Martin

 

I'd let go of the idea that "the coolant isn't staying in the rad long enough" -- it's an old wives tale that persists even though it doesn't work like that. If you get the coolant to a proper functioning rad and there's sufficient airflow across it, it's going to do it's job. Think about it -- the reason the water pump increases with engine speed is because the engine needs more coolant flow as speed and load increase. The faster the pump pumps the coolant (increasing with rpm) the less time it has to spend in the rad - but the more heat you reject. It's DESIGNED to work that way.

Having gotten that out of the way --- you're back to radiator capacity/efficiency and air flow. The 24x21x3 certainly should be more than enough - my LS3 (6.2L) runs an aluminum 24x16 with two 1" rows (about 3" thick) and it just sits at either the t'stat controlled temp (moving fast enough to keep the fans off) or the fan controller temp (moving slow enough to require the fans). With A/C on - my fans turn at 70% of full speed - and with the fans running that speed all the time, mine sits right at 194/5F -- i.e. - I have enough airflow for the t'stat to be in control of the operating temp. My rad config is tanks on each side - passenger side (lower) tank to water pump inlet; driver's side (upper) tank to water pump outlet -- so, cross flow.

Assuming your rad is up to snuff (I just don't know) - seems to me you have too little airflow across the rad. I also mounted my a/c condenser flush against the rad - sealed with foam tape - so that all air pulled across by the fans has to also come across the condenser. Your 1" gap may be hurting fan induced flow across your condenser. I run SPAL dual 11" fully shrouded puller fans controlled by a DCC PWM variable speed controller.

 

With the above suggestions, are you sure you got all the air out of the system? It's rather easy to do and if your gauge says 215 and radiator says 150s I'd say you have air or your gauge is wrong. Possibly a stuck t stat? Just a couple more things for ya to look at. Let us know what happens.

 

How in the hell did I miss that? Good catch cypris --- yup, somethin' else is fishy.

OP - is your gauge picking up temp readings from the ECU, or do you have a gauge sensor mounted somewhere? If a separate gauge sensor is being used, where did you mount it?

 

It's done this from the get go, after multiple bleedings, so I doubt air in the system. I have had it where the dash gauge reads nothing, and the Autometer reads normal, 2 different sender units, with the Rover ones being inline with the heater core hoses. That told me air in the system .
Temp gauge reads from the head. Autometer gauge. Reads the same as the ecu for the most part. I will double check today with the IR gun.

Dropped a new thermostat in it yesterday, and made a new lower hose,
Will see if that make a difference

Will update later
Thanks guys!

 

By looking at your pic it looks as tho the rad my be mounted to low. Thus making the rad full of fluid but the engine not full leaving alot of air in the system.

 

Think raising the rad will help any?

Just put it all back together and bled it. Stuck a 160 thermostat in it to test. Also have a 187 in the box.
At idle, sits at 180 degrees with the fans cycling on and off, with the ac on.
Raise the rpm's to @2500, temp goes up and up....I quit at @220 and dropped it to idle again, where it cools off back towards 180

Thoughts?

 

Just shot everything with the ir.
Top of the water pump by the outlet, @178, nearly the same as the ecm temp.
Top of radiator by the inlet hose....@140!
The top hose is maybe a foot long, with the steam line going into it, and a bleeder screw. Nothing but coolant from the bleeder.

 

If the rad isn't high enough it will help. Or you can mount a surge tank higher to fill it from.

 

You simply need the steam port hose with access to the highest part of the system to let the air out as you fill it. My steam line ties into my reservoir vent hose which is the highest part of the system.

 

My tank is higher than anything else in the system. The line from the top of the radiator goes up to it
Thinking air in the top of the radiator??

 

Make sure the lower radiator hose isn't collapsing from the WP suction. Rev the engine when it is hot, pretty easy to see. Some need a spring in the hose.

 

Where do steam vents tie in? Air in block wants to leave through those when filling

 

The highest point in the system must be the fill point. If it's a hose, put a tee in it and fill from there.

 

Yes sir. Just redid the lower hose to ensure that wasnt happening. Hose doesnt move

Just noticed the vent hose from the top of the radiator to the header tank is at room temp pretty much

 

Where do steam vents tie in?

 

Ok good....i just thought that was a overflow tank by looking on it from my phone.

 

Into the hose with the bleed valve. Upper radiator hose basically

 

It's under pressure.
It's what Land Rover use, as there is no cap on a radiator on a stock LR

 

When filling, is there anything to impede air leaving the block through the steam ports? If not, it shouldn’t be trapping air.