Rad Fans?

[Coops]

quick road test and all is good, temp comes down from half to just under so no fans on while driving yipeeeeeeeee
the fans do struggle though at idle and stay on and hold the water temp at 89C, so looks like these cossie fans are just coping,
have been given a spal VA09-AP8/C-54A fan to try by stuball,
are they any good? if so will get a second one and see if a pair of these are better than the stock cossie fans,

[stevieturbo]

[quote="stevieturbo"

You ultimately want to cool the engine. Water temp coming out of the rad is less important unless it isnt sufficiently cold to cool the engine.

Stevie
That is interesting as I was advised the opposite.
Give the car a quick blast and the water entering the rad may spike upwards. Why would you at that stage want the fan to come on? You may be going at 40 mph and the normal airflow will do the job.
Now position the switch near the outlet and that spike will not be seen, the fans not turn on etc.
the only time you need the fan to be on is when the water exiting the rad is getting too hot and hence needs cooled

Ian

Take a look at any modern car. They are all controlled by the ecu, and the temp sensor used is always towards the top end, ie hottest part of the engine. Be it the cylinder head or pipe leading to the rad.

Again, you are trying to control the temperature of the engine, not the water leaving the rad and going to the engine.


Not sure what your classing as a spike though ? For the most part the system is self regulating because of the thermostat. So yes temperature may fluctuate a little once up to temperature, but no big spikes as such.

[DEVONMAN]

quick road test and all is good, temp comes down from half to just under so no fans on while driving yipeeeeeeeee
the fans do struggle though at idle and stay on and hold the water temp at 89C, so looks like these cossie fans are just coping,
have been given a spal VA09-AP8/C-54A fan to try by stuball,
are they any good? if so will get a second one and see if a pair of these are better than the stock cossie fans,

Glad you got it sorted,
You could say the Cossie fans "are just Cooping"

Air temperature is unusually high at the moment so the Cossie fans will probably be more than adequate when the weather cools a bit.

We run a twin turbo 4.6 in a Sierra with standard Cossie fans and rad and a large intercooler up front and that copes ok. (Factory fan switch on the rad).

If your heater circuit (or bypass) is flowing hot coolant back into the block, things could be improved by limiting that flow even if it just during the summer months.

Regards Denis

[Robrover]

I use one of Brian Baskin's FK55 Delta Current Controllers to control the twin thermos on both my 4.6 SD1 and my V8 Discovery

www.dccontrol.com

Uses pulse width modulations to vary the fan speed, with the sensor being located in the base of the radiator next to the outlet pipe. A knob on the dash allows you to adjust the temp at which the controller starts to wind up the fans. They're used on a lot of muscle cars in the US and seem to work well, I have no overheating problems and it gets rather hot here in summer.

[Coops]

Denis what rad you using? cossie?
im using an audi one and starting to wonder if its too much for it with the intercooler,

we have removed all obstructions behind the fans, now lol,

this was the 10" fan set up,


where it all had to fit,


then the cossie fan set up,


start of the unwanted panel work and restriction removal,


All gone bar tidying up and bracing the anti roll bat mounts,


All under tray panel work tidied up along with the roll bar mounts, and front brace fitted, no heat trap there now


Fingers crossed this set works better, If not custom rad time,
Spal 11" fans, bugger they aint cheap

[DEVONMAN]

Yes it's a standard Cossie rad and fans.
The standard fans cowl is a good close fit against the rad with no real gaps for air to leak around the edges.

You should maybe consider limiting or re plumbing the bypass/heater circuit if it is currently returning hot coolant to the block without first passing through the rad. This modification on my Devon hotrod made a vast difference in traffic.

Regards Denis

[Coops]

been offered a cossie 50mm thick ally rad dual core,
BUT after looking at standard COSSIE RADS and ALLY RADS the ally ones don't have the pipe for the expansion tank to go to for filling up,
how do I get over this????
is yours the copper or ally rad Denis,
I gather stock rad and fans your using the copper one,????

[DEVONMAN]

been offered a cossie 50mm thick ally rad dual core,
BUT after looking at standard COSSIE RADS and ALLY RADS the ally ones don't have the pipe for the expansion tank to go to for filling up,
how do I get over this????
is yours the copper or ally rad Denis,
I gather stock rad and fans your using the copper one,????

Mine is a standard cossie rad with plastic end tanks.

We plan to swop to an ally one sometime (50mm Thick). It's in the loft at the moment.

The feed to the header tank will need to be a tee off the bottom hose.

Denis

[JP.]

Quit paying for Cozzie stuf m8.
All I see in the pics is plain Sierra, nothing fancy.
Have the same setup using a fine core Sierra diesel rad which came with the same fans. Early Sierra have the red fan blades and later Sierra's all came with the slim fit black fan blades.
Some diesel equipped Sierra even had the curved blades which flow even better.

Got it all of a Sierra myself ( scrapyard Smitht's Bloxham ) while I was over on shortbreak.

[Coops]

im having one final go at the warm issue,
going to put the fans in a cowl that covers the whole of the core and see if that is any better,
if not the car is off to serck marston motorsport for a custom rad and maybe intercooler,

[Coops]

well that didn't work BUT,
put the cossie fans up against the core and they brought the temp down slowly and even managed to turn on and off a few times, SO im thinking about building these fans into some sort of cowl that covers the whole core,

not sure why I never tried these fans on this cossie rad before

so now on the look out for a sierra rad fan cowl now lol,

[Eliot]

Quit paying for Cozzie stuf m8.
.

Agreed.
I assumed you just happened to score a cheap cossie intercooler or something. Going out and buying it because its specifically a "cossie" item is total madness - its 20+ old technology..

[kiwicar]

Hi Tony
There is a flaw in your logic here I'm afraid. Your problem is getting enough cold air to flow through your rad core at low speed, not heat transfer area in the core, putting a thicker radiator in will make this worse not better. The thicker core will offer more restriction to flow at low speed and there for less cooling. The answer here is to get enough cold air to flow through the rad you have (it has enough cooling capacity at high speed when there is enough flow from the motion of the car) divert the hot air from the intercooler away from as much of the rad core as you can, a plate from the top of the cooler deflecting the exit flow down and out away from the intercooler below the radiator would be a start. Put that oil cooler somewhere else so it is not dumping hot air into the core (under the right wingin a duct)? Put ducts all around the Rad so hot air cannot recirculate into the core from behind and close around the fans so they draw air through the whole Rad core remember you ideally want an opening about 2/3 the area of the radiator core on the inlet side to get maximum heat transfer efficiency provided it is cold fresh air, dumping heat into the radiator from other heat exchangers is uterly counter prroductive.
You should also look at getting the hot air from the radiator out and away from the engine bay as quickly as possable, there is no point in getting heat out of the rediator just to dump it directly into the engine block, remember on the rover about 25 to 30% of the cooling is directly from the engine block, for that to work at low speed you need to get the hot air from the radiator away from the engine surface.
Best regards
Mike

[Coops]

if the intercooler is my problem can I not change this?
smaller one in height???

[kiwicar]

Hi Tony
the intercooler is fine in that you still have plenty of frontal area in the rad with it where it is, what you need to do is get the hot air leaving it away from the radiator so it doesn't go through the core and warm it up, use the one you have but if you can move it forward a bit and put a deflecter after it that directs the air leaving it away from the front of the Rad. you have enough heat exchangers there in one form or another you need to manage the air flow better.
Best regards
Mike