Radiator sprays, and using water/metho mix

[rockcrawler31]

Lo outers oracle,

I'm looking at setting up a temporary spray system for my radiator for the upcoming KOTR competion this summer. ( i know, i know it's not the best solution but untill i can sort out a rear mount radiator then that's how it's gonna be)

I'm thinking a reservoir in the cab behind the seats with two windscreen washer motors going to a set of misters or bonnet sprays to spray iced water over the rad during long, high boost pulls in the higher speed sections.

Firstly - Can anyone recommend what sprayers to use? Garden misters, windscreen sprayers (from which model?), anything else?

Secondly - should i aim for a mist to get good coverage and let the fan draw the mist through? Or would that not take heat from the radiator fast enough? Should i be going for a fan shaped spray that might not fully cover the entire rad surface but gives it a good wetting where it does?

Thirdly - if i use iced water is there a danger of cracking something from when it hits the radiator surface?

4. - Somebody suggested adding metho to the mix to help it cool better still. Anyone got any experience if this is likely to be the case? At what ratio would it pose a fire hazard?

Go for it. (be nice, it's just an idea)

[toughnut]

Mate a mist is always going to be better than a gut load of water. You'll never get full coverage unless you have a heap of nozzles. Just so you know. This will do SFA to your EGT's. Just your water temp. If you have an oil cooler mounted in the same place then this will help oil temps too. No need for ice water as its the evaporation that aids the cooling. That is why a mist is better than a spray.

So basically get some mist nozzles from a hardware/gardening store and set it up so you get the best coverage. Remember that the spray area of each nozzle will be reduces considerably at speed. Don't go overboard with the amount of nozzles either as you'll have to carry more water for each extra nozzle you have installed.

Also you should conect it to a thermostat so that you don't have to be concious of it while driving at speed. It will just turn on atomatically if your water temps get to a certain level....... I have a brand new thermostate switch sitting here in a box that you can use for the comp if you want.

[tas80]

I was looking at adding water spray to my top mount intercooler when i had my 100 series ute.

Best nozzles I found were genuine intercooler spray nozzles from a Subaru STI, they will get a much finer spray than watering system nozzles and are designed to be run using a windscreen washer pump, they are available as a genuine part from Subaru. You want the water to be a fine mist as this will maximize the evaporative cooling effect.

I then planned to add a hobbs pressure switch so the spray would start automatically at close to maximum boost/throttle.

[rockcrawler31]

Mate a mist is always going to be better than a gut load of water. You'll never get full coverage unless you have a heap of nozzles. Just so you know. This will do SFA to your EGT's.
EGT's are fine, it's just that the engine now makes more heat at WOT than the surface area of a 75series radiator allows to get rid of with just normal air cooling.

Just your water temp. If you have an oil cooler mounted in the same place then this will help oil temps too. No need for ice water as its the evaporation that aids the cooling. That is why a mist is better than a spray.
That's what i thought, but i guess i was just wondering if a mist is even going to have time to really wet up the radiator at speed or just get sucked past by the airflow before it can get on to the rad and then evaporate.

So basically get some mist nozzles from a hardware/gardening store and set it up so you get the best coverage. Remember that the spray area of each nozzle will be reduces considerably at speed. Don't go overboard with the amount of nozzles either as you'll have to carry more water for each extra nozzle you have installed.
How do you reckon you'd go mating the garden stuff to the normal washer bottle hose? Any idea if it's all been done before with any level of success?

Also you should conect it to a thermostat so that you don't have to be concious of it while driving at speed.
Wayyyy too hard. temporary booty fab remember
It will just turn on atomatically if your water temps get to a certain level....... I have a brand new thermostate switch sitting here in a box that you can use for the comp if you want.
We'll se how we go, i got a Navi bitch to keep an eye on that sort of thing though.

[toughnut]

The mist will do 3 things.

1. It will cool down the air passing through it.
2. It will collect heat from the radiator fins as it passes by.
3. It will dissipate heat as it evaporates.

It would be worth having a look at those subi nozzles to see how expensive they are. It would be a piece of Pi$$ to adapt some garden mist nozzles to a windscreen washer bottle. If your truck is going to be at your place on your next break then I'll come down and we can have a bit of a muck around with it.

[Z()LTAN]

engine or intercooler rad?

[toughnut]

engine or intercooler rad?

Engine radiator. He has a water/air intercooler. He's just too much of a tight ass to do it properly so he's trying to find a cheap alternative to get him by.

[Z()LTAN]

Weird, when i did west oz challenge it was like 40 degrees and i was on thottle for a few mins at a time. Needle barely moved.

Before you waste a heap of time/money on water mist crap spend $250 on a new water pump and thematic fan clutch.

[rockcrawler31]

It's not weird at all.

The entire system is perfect, the rad's in great shape, and so is the thermostat, pump, coolant, and the fan is pretty stiff to move when the engine is off/roars it's tits off when you rev it.

My EGT's peak at 550-600 preturbo, and for general cruising around i've found that the cooling system copes fine when it's under 450c, but that is the tipping point. It doesn't instantly over heat at that point but once you go over that and hold it for ages then you can see the water temps creep.

It just seems that over that point is where the engine makes more heat than the system can get rid of. I'm not fussed too much by it, it's never been too much of a hassle but i just want that little extra leeway to hold it on song for this race.

Added that there's a lot of crap in the engine bay and airflow could be better it all adds up. And i don't think i 'll be spending 250 bucks on a misting system so i think it'll be substantially cheaper than replacing a water pump that's only got 30 thousand kays on it.

[Z()LTAN]

Do u think there is a reason why you don't ever hear of someone using a mist setup on an engine rad?

Dont bandaid the problem, look at increasing airflow through the radiator or decreasing your egts with more boost or water/meth fumigation.

[V.W.Dave]

he is about to do a big engine swop in the nere future so he is looking for a cheap way to get him through KOTR.

Milo a cheap trick we use to do on the dirt circle track cars was make the heater core hoses longer and run a small radiator on the floor of the passenger side of the car with a big electric fan on it. It would bring the temp of a 350 chev running a WOT for 20 mins at a time down by about 5*. You could do the same thing with a small radiator like you have on the back but keep it in the engine bay with a small fan.

[Z()LTAN]

Ah right, in that case just run it!

Remove your spotties to increase air flow if u have to

[rockcrawler31]

Do u think there is a reason why you don't ever hear of someone using a mist setup on an engine rad?

Dont bandaid the problem, look at increasing airflow through the radiator or decreasing your egts with more boost or water/meth fumigation.

Don't get me wrong, if there was an easy solution or even a definate (but exxy) solution i'd look at it. I've already got boost wound out as far as it'll go, it'll run 16psi at peak rpm/load and 10-12 psi all day long otherwise. But frankly for something that's only a problem now and then i'm just not inclined to go spending a motza on things that may or may not work. I don't know enough about water/meth injection to go playing around with that, and that means paying some clown a fortune to do it for me.

Nah, like Tex said, i love having a turbo diesel but if i blow up this engine i could really care less as it gives me an excuse to go LS V8 petrol. I just don't want to destroy it mid race is all.

I like the heater idea tex, i noticed that the heater helps a bit when on the road so having the extra cooling capacity certainly helps. I'm not sure my Navi would appreciate a heater at his feet so i might look at running the heater hoses to the back of the tray. Can anyone tell me if the factory pump would be able to push the water to the back of a ute through the heater hoses? or should i add a pusher pump as well?

[V.W.Dave]

If your going to run them to the back you will need a pump If it was just in the cab you wouldn't. Its not like having a huge radiator its just a small assisted one.

[Z()LTAN]

Fair call mate.

On the heater issue, the stock 'Pump' wont push that far and back fast enough for it to give any benefit. Look at fitting a small inline pump and switch it on as needed to introduce some cooler fluid into the system. Knowing that once its been switched on its all going to be hot for some time. The heater core itself wont do much. Perhaps look at fitting another smaller radiator to the rear of the car for the added capacity.

Good luck

[toughnut]

On my GU patrol I just ran the heater lines to the second radiator on the tray. This was sufficient for my engine but not sure about yours.

I have a davies craig electric water pump and thermostat sitting here at home if you need them. The water pump is perfect for this application and running it with the thermostat would be the preferred option as running your engine too cool will do just as much damage as running it too hot.

Oh and if you run the second radiator on the tray then block the radiator overflow on your front radiator and only run one on the rear radiator. Otherwise all your water from the rear radiator will flow out of the front overflow.

[rockcrawler31]

On my GU patrol I just ran the heater lines to the second radiator on the tray. This was sufficient for my engine but not sure about yours.

I have a davies craig electric water pump and thermostat sitting here at home if you need them. The water pump is perfect for this application and running it with the thermostat would be the preferred option as running your engine too cool will do just as much damage as running it too hot.

Oh and if you run the second radiator on the tray then block the radiator overflow on your front radiator and only run one on the rear radiator. Otherwise all your water from the rear radiator will flow out of the front overflow.

Thanks guys. I might take you up on that pump offer steve. Only thing is that we'll have to figure out how to go from heater hose size up to standard radiator hose size then back again. I've got a little bosch water pump running my intercooler now and it's perfect for the job, it runs 3/4 inch hose in and out from my intercooler barrel, but even if i used that then any second hand radiator i get is still likely to be larger hoses anyway so the problem is still there.

I was wondering about your thermostat steve, since the engine already has one in it and blocks flow the the engine if it's not warm enough anyways surely a second thermostat in the heater line would be redundant, and secondly, since the heater line wouldn't get any flow with the thermostat closed chances are it would never actually open right? Just my first thoughts.

I'm wondering if the best place for this second rad is under my tray with a thermofan? I don't have the room on top of the main hoop because it will foul my toolbox, so maybe under the tray with a sheetmetal shield to stop rocks and mud getting thrown into it? or is that just going to stifle it's effectiveness even with a fan?

To be honest a 10* drop would do it. I've seen temps up to 110* but i'm also pretty vigilant so i've always backed off when it's got that high so i guess it would probably go higher if i let it. Normal operating temps are 90* odd degrees anyway so just having 10 degrees up my sleeve would probably give me the time i need to get to places where i'm backing off anyway.

[toughnut]

Thanks guys. I might take you up on that pump offer steve. Only thing is that we'll have to figure out how to go from heater hose size up to standard radiator hose size then back again. I've got a little bosch water pump running my intercooler now and it's perfect for the job, it runs 3/4 inch hose in and out from my intercooler barrel, but even if i used that then any second hand radiator i get is still likely to be larger hoses anyway so the problem is still there.
It wasn't a problem for me as it is not a high volume line. From memory the pump that I have here has 3/4 inch fittings anyway. Just get a couple of adaptors from a plumbing supply or hardware shop.

I was wondering about your thermostat steve, since the engine already has one in it and blocks flow the the engine if it's not warm enough anyways surely a second thermostat in the heater line would be redundant, and secondly, since the heater line wouldn't get any flow with the thermostat closed chances are it would never actually open right? Just my first thoughts.
Its a thermo switch rather than a thermostat. Just like you have for thermo fans. It won't stop the water flowing completely to the second radiator, its connected to the pump and will switch it on when needed. That way you won't get the full effect of the second radiator until you really need it and if you're running on a cold morning like the guys do in comps like outback challenge then you need this so your engine gets a chance to warm up properly before flogging it down a track.

I'm wondering if the best place for this second rad is under my tray with a thermofan? I don't have the room on top of the main hoop because it will foul my toolbox, so maybe under the tray with a sheetmetal shield to stop rocks and mud getting thrown into it? or is that just going to stifle it's effectiveness even with a fan?
Under the tray would be fine. You just need to have a think about how to best mount it and protect it. If you do this I'd suggest that you use an inline tap on both the intake and return hoses so if you do hole the second radiator you can just turn the taps off and not lose the function of your main cooling system.

To be honest a 10* drop would do it. I've seen temps up to 110* but i'm also pretty vigilant so i've always backed off when it's got that high so i guess it would probably go higher if i let it. Normal operating temps are 90* odd degrees anyway so just having 10 degrees up my sleeve would probably give me the time i need to get to places where i'm backing off anyway.

[rockcrawler31]

That all sounds pretty good mate. Especially the bit about the pump being 3/4"

[V.W.Dave]

Go to a motor bike wreckers. That's where we got our small radiators for the circle track. They run small hoses and are a little bigger then the one you have already.

[shakes]

I'm sure you have covered this already but.... What are your shrouds on the radiator like? What obstructions are in front of it? can the air escape from the engine bay?

[V.W.Dave]

The shroud from memory is fine. He has 2 mid size spottier in front but the are a long way in front. He also has the back of his bonnet lifted to let heat out. It's simply a big heavy rig with big tyres that gets pushed a little harder then the current cooling system can handle.

[rockcrawler31]

The shroud from memory is fine. He has 2 mid size spottier in front but the are a long way in front. He also has the back of his bonnet lifted to let heat out. It's simply a big heavy rig with big tyres that gets pushed a little harder then the current cooling system can handle.

Lol, you and i thinking of the same rig?

Mostly right, there's nothing in front ofthe radiator except the winch down the bottom of it. I built my lights bar for that very reason. But yes the bonnet is lifted slightly at the rear to improve airflow out of the engine bay and reduce the high pressure zones under there that would impede flow due to all the other crap that is in there. It worked a little and on a cold frosty morning in the mountains you can definately see the warm zone on the bottome onf the windscreen.

[V.W.Dave]

here you go this is his rig. I don't know why I thought you had spotties there I know you have that flip up light bar. The barwork from memmory is a little more ummm yahh its more now
But then again with a owner like Milo that has a thing for young goatswho knows what it looks like since last time a seen it

Pore little billy goat didn't know what he was in for

[shakes]

Just as a test drop the bonnet back down... Chances are it's working to let the air flow flow through. But see if the extra force of air all following the same path creates that last little "vacuum" it needs to keep it cool. Very unlikely to work but it will only cost you your time.

[rockcrawler31]

GOATY GOODNESS!!!!!

Me + bottle of rum + billy goat = fun for everyone except the goat!!

[rockcrawler31]

Just as a test drop the bonnet back down... Chances are it's working to let the air flow flow through. But see if the extra force of air all following the same path creates that last little "vacuum" it needs to keep it cool. Very unlikely to work but it will only cost you your time.

It's always worth a try

Cheers mate