Radiator misters orifice size

[lostagain]

My 5C came from the PO with misters. I got them to work again last summer, as I can use them on a hot summer day going up a hill. There are four nozzles in front of each radiator. The mist is very fine and hardly makes a difference in temperature. I am thinking about drilling the orifices larger for more water.

Thoughts, advice?

JC

[wg4t50]

JC,  I made my own mister system, keeping it simple, I used a window washer pump for a car, using the same size hose, found a copper tubing that fit correctly into the hose (small), using a side cutter pliers, mkes the perfect spray pattern,  just sniped off what length needed, then securing it in the sweet spot and using two locations and using window washing solution (to keep from corroding the nozzles, used it very cheerfully on the 12V-71 and then the 8V-92 on my MCI 7. Turn it on at  bottom of mtn and go up at WOT.  
Cheap & tachy works great in this case.

[lostagain]

wg4t50, thanks.

How big were the orifices of your nozzles? Are you saying they were windshield washer nozzles? That would put out way more water than mine. Which is what I think I should try.

Mine are the store bought brass nozzles with really small holes you can hardly see through. The mist is really fine like a fog, like I remember seeing everywhere in Ft Worth, Tx when we went there in July a few years ago.

JC

[Busgeek]

I built a cooling spray system using 1/2 inch hose which I secured at the top of the core with 1/8 in as I recall holes every 6 inches hooked  into the fresh water system with an electric valve.  Cleal the radiator with lime away when needed.  This works great.  Hope this helps.

[TomC]

When I turbo'd the 8V-71, I also had the radiator rebuilt from a 5 row with straight fins to a 6 row with serpentine fins (the largest I could go).  The radiator still didn't cool on an over 80 degree day on a long pull, so I installed 15 misters from Home Depot tied into the water system through a 12v solenoid valve.  That still wasn't enough.  The best was just simply drilling out two of the misters with 1/16" drill.  So in retrospect, I would just suggest using two 1/16" hole misters-one each side for a two radiator MCI.  Granted, you'll get some mineral deposits, but once a year treatment with CLR does the trick.  Good Luck, TomC

[rv_safetyman]

JC, I have tried most everything on my air-to-air "radiator" (water cooling is no issue).  There are all sorts of theories on how to use misters.  First theory is to point them away from the radiator and cool the air coming in before it get to the radiator.  Never worked for me.  

I then tried all sorts of nozzles - many intended for the chicken raising industry to cool the chicken coops.  I used up to 8 of these nozzles at one time.  They were aimed at the "radiator" and put out a very fine mist (almost no wetting of the cooler).  Some of the nozzles were pretty neat in their design.

The third approach is to "flood" the radiator and that is where I am now and it works great.  I use two of my fire suppression system nozzles:

http://www.medibix.com/detail.jsp?view=detail&sku_id=948282&product_id=456462

From the details on that page, you will see that the orifice is 0.094 and the flow rate is 0.8 GPM.

That is a ton of water, but I control the solenoid valve with a switch that I turn on for about 3 seconds and then wait for up to 10 seconds and repeat as needed.  I watch my SilverLeaf for manifold air inlet temperature and can watch a DRAMATIC drop in temperature.  Note this is an air system, but I would expect to see a very significant temperature drop in water temperature but with a longer reaction time.  

The big impact is to make sure you stay ahead of the NEED to use the "misting"/flooding system.  Catch it early and you will not have any issues.

I use water from the domestic supply tank and have not noted any buildup on the fins.  Fortunately, I don't have to use it much.  If I do get a buildup, I will spray it with something like CLR and it should be fine.

BTW wg4t50, your approach sounds simple and effective.  It is a "flood" type approach from what I can tell.

TomC and I were typing at the same time, but his approach is the same as mine - pour the water to the system.

Jim

[skihor]

With 4 on each side I used 1 GPH mist "heads". 1 1/2 GPH "heads" were too much. Through trial/error that was the difference between near total evaporation or excess water running out. Spray directly on the rads, way more BTU rejection than spraying out to the incoming air flow. Besides, if your in a humid area there is NO benefit to cooling the air. Best is to have a seperate tank with distilled water, otherwise clean the rads after each trip. I use directly from my fresh water supply. I use a Shureflo or equlivelant RV water pump with at least 35 PSI to achieve the full benefit/atomization of the misters. www.plumbingsupply.com
My original (4 head) set-up is approx 6" from the rads. My current set-up is a 2 head @ 2 GPH approx. 10" from the rads. I set it up according to the spray pattern for maximum coverage. I run a small fuel filter in line just before the "inlet" on each side. Going to the 2 "head" set-up cut down on plugging considerably. I used all-thread rod top to bottom with a "U" shaped copper line zip-tied to the all-thread rods. Bottom of the all-thread was "pinched" with a nut on either side of the bottom "deck" and a "jam" nut against the top. I installed a switch on the dash with a bright red light indicater light. I forgot to turn it off more than once and @ 8 GPH your water supply goes fast. It really sucks to go dry camping only to get there and not have enough water for a shower.

Don & Sheila

[edvanland]

On my MCI 7 with 8v92 Geoff put in a system using water nozzles from a garden sprinker system. When the temp hits 175 I turn them on and watch the temp stay put or go down. Before I had them house nozzles, did not work. I am a happy camper as I do not want to spend another $10,000 on a in frame overhaul, water is cheap. I use the house system to supply the water. Course I live where it is cool, if it under 100 degrees it is cool and also a lot of mountains. You see I live in Arizona, LOL
ED
MCI 7

[wg4t50]

As I mentioned, I cut the copper tubing with side cutters, this left a very narrow slit in the opening. it  sparyed a fine fan mist like, I aimed it at the center of the fan, It is a small amount of washer fluid being used, and using two, one on each side of the fan hub, worked great.

I could not find a fancy store bought orfice, so why when I looked at the copper tubing after being cut with the side cutters, looked  good to me, so tried it and bingo, worked great.  This was first used on the 12V-71 and later with the 8V-92 in the MCI 7, these coaches dont cool  anyway, why the radiator across the rear with a pusher fan.

Like I mentioned, keep it simple, this is not a complicated ordeal.  Used a switch on control panel, turn on when needed, turn off when not.
FWIW

[luvrbus]

I live in AZ and never had misters I could pull the mountain from Laughlin to Kingman on Highway 68 in the middle of Aug that stretch will separate the men from the boys lol

When it was 115 to 118 degrees out side with a 8v92 500 hp and a 740 Allison in a Eagle I never had a heating problem 

I had enough radiator to do the job with a 32 inch fan move enough air with the water it's not a problem, to me misters are just a band aid that is my take on misters


good luck

[skihor]

I live in AZ and never had misters I could pull the mountain from Laughlin to Kingman on Highway 68 in the middle of Aug that stretch will separate the men from the boys lol

When it was 115 to 118 degrees out side with a 8v92 500 hp and a 740 Allison in a Eagle I never had a heating problem 

I had enough radiator to do the job with a 32 inch fan move enough air with the water it's not a problem, to me misters are just a band aid that is my take on misters


good luck

Good point. In my case everything within reason/budget was tried... larger blowers, smaller pully, outside scoops, completly sealed rad compartments, new rads with serpentine cores, new water pump/Tstats, throttle control, seperate trans cooler, etc... My problem was simply not enough rads for the hot rodded 6V92 conversion. This summer, after 30 K + miles of nail biting summer traveling over the last 8 years, and 1 set of replacement heads, I had 2 additional custom Rads built which has solved 95% of my cooling issues. I'm not going to give up that horsepower without a fight !! Currently I have 2000 CFM fans on the extra rads. I'm going to upgrade that to Zirgo 3650 CFM fans. If that's not enough I'll have to have some custom shrouds made. The current set-up cost me close to 3 K. The mister system cost under $100 and almost got me by. Over heating the engine cost me 6 K....

Don & Sheila

[lostagain]

Thanks all for the great comments.

To clarify my circumstance, here is what I have:

it is plumbed off the house water system. Controlled by a solenoid valve with a switch at the cockpit. The house water pump has to be on to supply the pressure, and I turn it on and off at the dash.

I would rarely use it. I don't have an overheating problem unless going up a hill in hot weather. It would just be nice to have functionning properly to cool off, rather than down shifting just to stay cool. I have new MC9 rads, air tight rad shrouds, etc. Lots of power with the 90 injectors. I can manage the heat most of time by watching my right foot. Working misters just would be nice to have.

The PO had installed it, but never used it or so he told me. Probably because it doesn't really work with such small orifices in the nozzles that put out just a fine fog.

I can see clearly from all your answers that I will start by drilling the holes bigger to 1/8" to flood the rads. Of course, I won't know the results untill next summer... I just got to this item on my winter "to do" list.

Thanks again,

JC

[TomC]

Ed mentioned he turns on his misters at 175 degrees-which I think is a bit low.  My thermostats close at 175, and are fully open at 185. When I see the temp starting to creep up to 200 degrees-that's when I hit the misters and within about 5 minutes, will bring the temp back down to 180 when I shut them off.
I wish I had the space for a larger radiator and didn't have to use the misters (I agree that misters are a band-aide). When you have an engine that originally put out 258hp and 677lb/ft of torque that now puts out 375hp and 1175lb/ft torque-and after enlarging the radiator to the biggest, cutting two vents in the engine door, bigger air cleaner, bigger muffler, auxiliary transmission cooler to take the heat strain off the radiator and it still overheats-you have to use misters.  Good Luck, TomC