Decided this week to redo and improve my radiator misting system. Replaced the tiny irrigation tubing with 1/2" PEX line and since my 24v gate valve decided to die, I just installed a 12v water pump that pulls from my 150 gallon fresh tank. I used a set of lawn sprinkler misters but I'm not super happy with their performance. They work fine spreading water over the entire radiators when Coach is at idle but when rpms are raised the water just gets sucked in at the point it's leaving the sprinkler head and not spreading over the radiator surface anymore. So I'll have to redo that part of the system today removing the single sprinkler heads and installing some sort of mister heads (several of them) along the pex line that is crossing the entire radiator. This is how the old system I built worked but they were drip line heads and they just didn't spray much water. Anyone have a mister head they like?
I just used 1/2" ridged plastic ppipe and drilled 1/16" holes in it. Works fine for 25 years.
The hurricane of air passing will render any mister useless.
As you are doing, get the water out in front of the radiator, and just let it go.
The hurricane will distribute.
Spraying from the edges won't get the water to the middle, rigging some piping up on the inside of the screen right across in front will accomplish a wider distribution.
Do some experiments with the engine spinning flat out, and see what gets the water where you want it, and biased for the forward movement of the coach through the air.
Happy coaching!
Buswarrior
Curious what the water looks like coming out of 1/16" holes? Does it mist or dribble lol?
I agree, the hurricane does crazy things to the water. Just wasn't sure if anyone had a specific mister head that they loved.
I have never watched the spray from the 1/16" holes but the temps come down. I have a center pipe and several branches off to distribute the water to various places on the rad.
Stop in at the local NAPA and pick up a few aftermarket replacement windshield washer nozzles (and universal washer pump if you need a new one) from a car or truck. I would pick something like a full size van that has a large windshield. Common sense would deem the nozzle to be larger than that found on a Prius. Look around in traffic or spend an hour in a used car lot to find which ones have the pattern you like. Nice and simple.
I originally bought a 15 mister kit from Home Depot and mounted it in an S in front of the radiator. Worked soso. I then drilled out two of the misters with a 1/16" drill and now it really dumps water on the radiator. You need to dump lots of water-like a gallon a minute on the radiator to have any affect. I just use the fresh water from the tank with a 12v water solenoid. It works well-I can be in 108 degree weather and it will pull the temp down within 2 minutes. Good Luck, TomC
I can't remember if I have 1/16 or 1/32 holes in the PVC pipe I used for my spray system. It is mounted at the leading edge of the radiator and aimed straight across instead of into the fins. It seems to word pretty fast. One thing I found useful was putting the valve on one of those spring wound countdown timers so I don't forget to shut it off. My timer is up to 15 minutes but 5 minutes or so is generally enough.
Nice great ideas and info. Here's what I did while you all were replying today. I just drilled super tiny holes in the PEX pipe. The drill bit was like the size of a dental drill bit. Like a needle. Super teeny tiny. Works perfect. I jammed the throttle into full throttle position and observed my system and it's distributing the water nicely and dumping a TON of water using a 12v pump. I think it will work better than the old drip system I was using before.
Hello Scott,
I have been restraining myself for 2 days, but I can't hold back any longer.
....but, how about your Mrs. system...?
Sorry
Seb
Consider a filter to avoid hole plugging.
Decades ago Ford started using nozzles that have a discharge chamber which causes the stream to oscillate across the windshield, some of those might be good, and maybe more clog resistant.
Jim
I used to use distilled water to avoid the hard water scaling on the fins of the radiator, but Ii switched to HD piece together 1/2" pvc with brass and rubber tipped nozzels drilled to 1/16th, as in Tom's idea, connected to my fresh water tank and it's pump and descale it every couple years with radiator fin cleaner, seems to do fine, lvmci...
If you want a source for distilled water, use it from dehumidifier.
Scott I always use windshield washer fluid. It keeps the radiator clean and do not have to worry About it freezing in the winter.
Are you going to come by Blytheville this year.
uncle ned
Wow I drove my Eagle for 15 years in AZ (110 + degrees ) never had a misting system on my 8v92 never needed one
Cliff, was yours set to 500hp with smoke control turned off? My coach is 40,000 pounds plus my 7000 truck behind it. 47,000lbs and a 500hp 8v92 turbocharged is gonna make some heat.
Quote from: Scott & Heather on August 30, 2019, 07:43:02 PM
Cliff, was yours set to 500hp with smoke control turned off? My coach is 40,000 pounds plus my 7000 truck behind it. 47,000lbs and a 500hp 8v92 turbocharged is gonna make some heat.
Nope it was 525 hp with no smoke control lol my trailer and the Lexus weighed around 8,000 and bus was a tid bit over 40,000 lbs,it's not the engine it is the poor cooling system on the MCI with the side mounted radiators ,that system was never design for high HP .I thought you had solved the overheating with some type water wetter
Wow, that could be pretty expensive for some.
Quote from: luvrbus on August 30, 2019, 07:59:32 PM
Nope it was 525 hp with no smoke control lol my trailer and the Lexus weighed around 8,000 and bus was a tid bit over 40,000 lbs,it's not the engine it is the poor cooling system on the MCI with the side mounted radiators ,that system was never design for high HP .I thought you had solved the overheating with some type water wetter
Ok you win lol. I can't even imagine even more horsepower and more weight stuck on the back. My coach runs cool all day long in the 70's and 80's. But once it hits the 90's or more, it just struggles a little. Add hills to the mix and I'm hitting the misters unless I want to drive 55mph all day long. I solved my major overheating issues by getting my turbo rebuilt. That fixed it for the most part. But she still runs warm on hot days for sure. Cliff, what's your temp limit on an 8v92 with a 500hp setting? How hot can they get without damage?
I had a Kenworth cabover with 8V-92TA 435hp mechanical that never had heating problems. But then again, had a 1350 radiator, and the advantage of front engine.
I have a 6 row radiator on my 8V-71T with air to air intercooling and still needs misters in over 90 degree heat.
If I had the Fires of Hades burning in the back of an older MCI...
And knowing the Devil was involved in coming up with that leaky twin radiator and fan door set-up... where air goes past, instead of thru...
And the fan compartment typically has corrosion issues...
I'd be wondering about carving all that out and grafting the D model style cooling system on the back, and a suitably huge radiator...
We need a Busnut Moses to lead us to the promised land...
I'll hold the trouble light?
Happy coaching!
Buswarrior
I used 1/8"NPT car wash nozzles on my mister system like what is in the gun barrel at a self serve carwash. I have mine turned up and out about 20 degrees, threaded into 1/2" pvc pipe. Very cheap and simple. Been in place 18 years. I only need it climbing Wolf Creek Pass eastbound, then only very little. Very little heating issues since I replaced my fan with a new one back in 2008.
David
I use adjustable spray nozzles for garden drip systems. I have them set all the way open so 10-15 seconds on the toggle switch is all I need to soak the radiator and bring the engine temp down for a few minutes.
Since then I installed a second radiator 1' x 3', 3" thick with 3 fans and haven't had to use the water sprayers yet.
Quote from: Geoff on September 01, 2019, 12:39:00 PM
Since then I installed a second radiator 1' x 3', 3" thick with 3 fans and haven't had to use the water sprayers yet.
That's a great alternative. A trip to the picknpull to grab the radiator/electric fan/housing from a newer car, mount inline with a simple on/off for the fans when needed.
The only drawback to a second radiator is finding a cool place to mount it. My GMC RTS has a separate upper compartment above the engine so that is where my generator and second radiator is mounted. It draws cool air from the top of the roof and discharges the hot air out the back louvers.
Yeah I have no idea where I'd put another radiator. I have twin 8 row units that are relatively new. I do wish I had the d style radiator and fan setup. BW, I'm definitely not going to lead anyone to the promised land because Heather and I are already in the early planning stages of building a truck conversion. As much as I love my bus, there comes a time when the lightbulb flicks on when you're at the repair shop and the sign reads:
REPAIR RATES:
Trucks: $90 /hr
Buses: $150 /hr
And the cost of a bus slack adjuster is $200 and the cost of a truck slack adjuster is $75...
And your bus is overheating because the engine and radiators are slapped on the rear of it...
And you're about to rear end a semi truck who panic stopped in front of you and you're 6 inches from the windshield and hoping you stop in time to prevent your face from leaving a mark on the back of his trailer...
And your head and arms are jammed between the ceiling of your engine compartment and a turbocharger you're trying to replace....
And no matter how much spray foam, Sheetrock, rubber, and reflectix you laid on your bedroom floor, after a 9 hour driving day, your bedroom is hot....
And you get 5.5mpg no matter what you do...
And you think to yourself:
"I'm not a bus guy anymore. I'm a truck guy."
So someday, this is in our future:
The end.
Very good.
The trouble with busnuts, blinded by an emotional bond to a machine...
The forest becomes obscured by trees.
Most don't understand that your machine is supposed to be a supporting player. Many coaches spend all their time being the star, and many busnuts like it that way.
Spend some time paying attention to highway tractors. I have noticed many of those toterhome things have the cheapest spec truck under them... no surprise?
For the same reason we build our own coaches, i'd be looking to choose the chassis in the trim and options I want, and get a box put on it. Many, many regional outfitters put boxes on trucks and change the lengths of frame rails.
And the walls are square in the back...
Happy coaching!
Buswarrior
Cut the horsepower back about 75 to 100. Sure you'll lose some speed on the hills, but the engine will last longer and you'll be done with heat issues
I don't understand the misting systems you guys build,here in the desert heat you cool the air and you get better evaporation and cooling with smaller holes and more pressure best I can tell you guys are just flooding the radiator ? not misting
Cliff, there was a discussion a while back on this. Misting vs flooding. I agree that misting works better in terms of actually cooling the air before it hits the radiator, but because of how much air is getting sucked in, I can assure you it works better flooding my rads. My first system I've used for three years was misting them. This flooding system brought the temps down faster more degrees of drop, and longer. It's night and day. The cooling effect of flooding them works so so much better.
Oh I wish the engineers of days gone by were still here to explain this...the stuff that got banged out in the old chat rooms that was lost as soon as we logged out...
Evaporation and what not, getting the water onto the rad surfaces is the point of the exercise.
Where we screw up is not getting the water onto enough surfaces, because our delivery methods are inadequate for the hurricane blowing past.
Some "misters" don't do squat when the fans are at full tilt AND the coach is moving down the road at speed. The water ends up blown to the sides someplace, and not get on the rad surfaces.
Oh well, the dolts that pissed off the engineers by arguing stupid $#!% are also gone...
The decay of our society: celebrating stupidity and laziness then discounting knowledge and hard work
Happy coaching!
Buswarrior
I think evaporation would be the way to go if you had enough room to mount a system farther away from the radiator to be affective, it would cover the entire radiator with cool air,when you get down to it the right foot comes into play with cooling a beast
Some drown them because their system isn't misting properly because of airflow issues disturbing the spray pattern. Probably using some food dye it the misting water temporarily might show how the spray is working going down the road.
I drove these 2 stroke Detroits in the 70s and 80s. A lot of times in the heat of the British Columbia Interior, up and down hills. We never had misters. We were trained to drive them on the governor at high rpm. We were also taught to watch the temperature gauge, and to back off and down shift when it went up toward 200F. I don't remember overheating issues.
What has changed?
3 things I can think of:
- Our buses were well maintained.
- All we had was manual transmissions that don't put extra heat into the cooling system.
- A lot of today's busnuts don't know how to drive them. They lug them with a heavy foot.
JC
Clifford I had misting sprayers and they cooled some, drilled out the holes and it cooled faster and to a lower temperature, tom...
Quote from: lvmci on September 03, 2019, 09:14:47 AM
Clifford I had misting sprayers and they cooled some, drilled out the holes and it cooled faster and to a lower temperature, tom...
I am just saying if there was a bigger air space for the mister to cool more air it would work,At the restaurants we run 350 PSI with tiny holes and you can hardly see the mist and it drops the temperature 30 to 35 degrees on the patios,I am not fan of flooding the radiators it does a number on radiators over the years
I have always had good luck with drowning the radiator to cool the engine. However, you can use a lot of water this way. When I moved from CA to AZ I pulled a 10k trailer behind my bus several times.
By the time I got to AZ I would have to refill my 100 gallon water tanks, so the water would last 600 miles having to use the sprayers on every grade. Without the trailer I didn't need the sprayers.
Couple thoughts:
Lost again: my bus is maintained well. But I'm 47,000lbs gross when towing my Expedition. How heavy were you with passengers?
The Allison auto does add a ton of heat to the cooling system. So if you were driving a manual, I agree that's likely a big cause of why you never had overheating issues.
My coach has been turned up to a 500hp setting. I love it. It's worth having to watch the gauge if it's really hot out. I only have to be careful in 90's or above heat. Most of where and when I drive, this isn't an issue. My tours keep me north in the summer and south in the winter.
As for flooding the rads, I agree with Cliff, if the system could mist the entire radiator it would have an amazing cooling effect. But I tried this using patio misters and once the rpms went up, the mist disappeared and there were just small wet spots on the radiator right where the misting heads were located. Just didn't work effectively. My new system does flood them but the downside is that it absolutely uses a ton of water. I need to find the perfect balance somewhere in between.
I put in sprayers with 1/2" pex in a square and 1 pipe down the center. drilled 1/16" holes every 6 inched around the pipe and down the center. When coming down Bakers grade it did bring down the heat which has never really that bad 180 190 but noticed oil all over the rear on the coach. It was basically steam cleaning the engine for me but what a mess it mad with the old oil from the rear of the motor. Its clean now just don't use the misters until it needs it again, LOL :D
Dave that brings up the other benefit of cooling the radiators, the water spray then gets sucked down to the road hitting the engine, like an old oil bath air filter, cooling the engine block and in Dave's bus, cleaning the engine as a side benefit, maybe I should put some 409 in the mix and later some gold leaf, making my engine a gold 8V92, a step up for me! lvmci...