I will be replacing my drive tires this spring and was wondering about filling them with nitrogen in lieu of air. I have seen/heard of a lot of good things about that, are there any bad things?? Anyone have some experience on this?? Thanks and have a great day ---- Fritz
I think it's a waste of money. Just a money maker for the tire shop. Ordinary air is 80% nitrogen, so how much benefit do you think there could be by adding another 20%?
My experience includes using 78% nitrogen in tires for all of my life. That has been a high enough concentration to satisfy my requirements.
There are some minor advantages to Nitrogen-- no disadvantages other than perhaps cost. Guess my answer is "it depends on the price". If $5 or less a tire-- not a bad idea. If just a dealer profit item, no thanks.
I guess there is not oxygen; therefore no oxidation. Don't know if that feature improves the inside of the tire materials and the inner part of the wheel? All my old cars have nitrogen as they all have gotten new tires at some point from Costco. They use 100% nitrogen. Problem is, I have to go back to them whenever I need to increase the air pressure. It's not a big deal, all I do is drive up to the tire shop and they do a courtesy pressure check each time we go. It's about once a month.
All aircraft I ever worked on ( since the B29) used dry nitrogen in tires.
I always thought it was to keep the wheel & tire in balance.
Plain air contained moisture which would freeze @ altitude. B29 came down real slow.
B47, Kc135, C130 came down pretty darned fast
You only have to ride out one landing with a wheel/tire out of balance to make you a believer.
The problem is the other 22%!! Water vapor (humidity) can make up as much as 5 percent of the volume of air under worst-case conditions. You get rid of that 22% and you get rid of the water vapor problem. But if you check and adjust your tire pressure regularly, you should be okay. They say a majority of people, including RVers, don't do that.
Before I added a tpms system, I checked tire pressures once a week. Now I check them daily when using the RV.
By the way, I use system air from the coach for the tires, which should be pretty dry.
Should You Fill Your Car's Tires With Nitrogen? (http://www.edmunds.com/car-care/should-you-fill-your-cars-tires-with-nitrogen.html)
I bought a bottle and reg for filling bike, car, motorcycles and trailer tires. When I bought it my daughters cars and my wife's car had low profile tires that are very expensive. They are NEVER going to check the tire pressure! I had bikes motorcycles cars etc. To keep up with and if there is a chance it helps maintain tire pressure and minimizes loss it was money well spent. One tire replacement would pay for the setup. I think I do see a difference in the frequency of needed re-pressuring of the tires. Our airstream held for two years never needing to be topped off.
Thanks all for the input, I guess you do what feels comfortable and dont fuss about it. Thanks and have a great day ---- Fritz
As a retired Aircraft and Powerplant maintenance crew chief for one of the major Airlines with 41 + years service I can say dry nitrogen in the aircraft tires is used so they can recap 15 + times and carcass not rot from moisture. There is also the fact that dry nitrogen does not expand as much from heat. I see no major need for it in my coach or other private vehicles but it wouldn't hurt either.
Bill
I actually see THREE choices: "regular" air (with moisture), dry air and Nitrogen.
No difference in PSI change with temperature change between dry air and Nitrogen-- for all intents and purposes both follow the Ideal Gas Law.
Both are better than "regular" air, like from those gas station coin op pumps, as water and water vapor certainly do not follow the Ideal Gas Law. So "regular" air has a larger PSI change for a given temperature change-- not a good thing.
@Brett there is a 4th choice... CO2 which is what I use. I don't know how it compares to the other gases. I use it mostly for convenience. I don't have to start up the coach and wait for it to build pressure before inflating. I can inflate the tires the night before I leave so that I don't have to get up early before the sun hits the tires and it's a dry air source. Bonus points for being pretty cheap once you have the tank and pressure regulator. Additional bonus points since I can take it with me 4 wheeling and deflate my tires and re-inflate before I get back on the highway.
see ya
ken
Ken,
CO2 should follow the ideal gas law, same as Nitrogen and dry air.
No idea of the benefit/penalty of using CO2 on rubber and aluminum.
One of the advantages of Nitrogen is that it is inert.
Brett
Fritz, Ken, Brett and others that are interested, I was generating this when Ken and Brett chipped in:
OR, like Ken and I have,
One can invest in some excellent
insurance and convenience called a PowerTank.
http://powertank.com/category.rv (http://powertank.com/category.rv)
By getting "
a smart design, high performance, guaranteed reliability, and best warranty in the industry" (their words) portable air system (CO₂), you can significantly reduce the portable "air" system storage footprint, the portable "air" system overall size, the frustration of the alternatives, and you can increase the flexibility that you will have in terms of access to an air (CO₂) system anytime, anywhere you need it without having to fire up the coach and wait for the air system to build and then rebuild pressures.
- It's nice to be able to easily carry the system around (car, boat trailer, motorcycle, golf cart, ATV, neighbors', including wherever/whenever a pneumatic nail gun, chipping hammer, chisels, impact wrench, power ratchet, sander, grinder, blow gun, nozzles are needed).
- It's nice to be able to run any and all air operated tools, up to and INCLUDING a 1000Ft./Lb. torque impact driver. Power Tank Impact Wrench IR 2135 1000 ft Lb | eBay (http://www.ebay.com/itm/Power-Tank-Impact-Wrench-IR-2135-1000-ft-lb-/230970193714)
- It's nice to be able to top off (or fill) coach tires in seconds versus minutes.
- It's nice to use an outstanding quality regulator, an oil filled analog (or digital) pressure gauge, industrial clip-on and other chuck fittings, that work right and are exceptionally well made and durable.
- I thought that I'd eventually invest in a digital gauge, until I used the oil filled analog that came with my system. No way, now that I've used it. The rubber coated, highly durable analog lets me sense, in a damped fashion, exactly what the chuck is providing for gas flow AND it is accurate +or- 1.0 psig (+or- 0.75% of full scale).
- It's nice to know that dryness is not a factor, especially if you use powder balancing. I used to use powder, which I liked, but have moved to Centramatics, which I like even better and find to be better KISS-wise. Dryness is not an issue if you use air off your coach, but it is a big issue anywhere else. Few tire services, even truck tire services, properly service and care for their air separators. Filling stations -- forget it!
- It's nice to know that corrosion is not an issue. CO₂ vapor is a dry and inert gas. It poses zero corrosion issues to either the rubber in your tires and stem seats or to any metals involved, including steel and aluminum rims and valve stems. There is far more to be concerned about from the moisture permeation into the rubber tire compounds from the surface that you are parked on (park on a moisture impervious shield) and from any moisture that was in the tire before you inserted the CO₂ (you cannot evacuate all of the air before filling or topping off with CO₂ -- that's where an initial fill with dry air becomes very important).
- It's nice to know that unlike air, and to a lesser extent N₂, a CO₂ cylinder is going to last a very long time. It is stored as 10# of liquid at a relatively low pressure (800 psig, unlike N₂ which is much higher). Internal to the cylinder, CO₂ boils off to a vapor that is totally inert (brass and steel and stainless steel valves and regulators are equally and totally unaffected).
When it is time, it's easy to find PowerTank refills (paintball supply stores, welding supply stores, gas refill services, etc.) and my 10# tank generally lasts more than a year. Refills are usually $12 to $14).
Watch e-Bay for deals. PowerTanks often appear for under $200 because a lot of off roaders and trucking outfits use them.
It is kind of a luxury item, in that there are less expensive ways to skin the cat, but the convenience and versatility means that I use it much more often than I would any of the alternatives (or become frustrated by the inconvenience) in, for instance, "bringing a tire up just 5 lbs - to PERFECT".
KISS principle applies.......BIG time!
In terms of negatives, beyond the cost, I have found only two:
- One must know the weight of your empty tank and then check to make sure that when you have it filled, they don't over fill it. I thought that was a silly requirement, until Maine OXY/Acetylene put 12 lbs. in my 10# tank. It blew the safety seal about two weeks later. Maine OXY repaired (just replaced/rebuilt the seal) refilled, at no cost, no questions asked, but they didn't pay for my ruptured carrying bag (Speed Bag). I had weighed the tank, and knew it was overfilled, but then I didn't store it in a COOL place until I had used off the excess. Thus, the safety seal ruptured in my trailer on a hot day.
- Most bicycle tire tubes are made of a cheaper rubber that will not hold CO₂. Don't know why this is. Some tubes are of a higher quality and the CO₂ works fine. Others won't hold CO₂ overnight. Strange little quirk that I've never found a good explanation for. But, it is a prevalent issue as you will find many instances on the internet. For me, it was time to change my mountain bike tires and tubes, so I don't have the issue any longer, but I would say that up to 75% of all bicycle tubes are permeable to CO₂
So, just saying, there are usually a range of options, and before Ken, I hadn't seen anyone else mentioning CO₂. I was fortunate enough to get my complete PowerTank setup at a big discount from George Stoltz, when brother George went back to Sticks 'n Bricks. Thanks again, George!
Besides Ken, I know Dave M has one, including a spare tank. I recall that he likes his as well. Seem to recall that Brad M has one also. Don't know how many others have them.
I do know that several SOB's have invested in PowerTanks after I used mine to help them out of inconvenient situations.
Anyway, a few items to think on.
Hope this is of some use to you all.
Neal
Neal,
Correct and agree, I have the 15 lb size, cost $15.00 per refill at local welding supply shop. Can sure make the 3/4" impact wrench dance nicely @ 200 psi :o
And sure does top off a tire so much quicker than any air hose I have used. ;D
Dave M
@Neil just to clarify I don't have a PowerTank. I really wanted one but couldn't justify their prices! Holy crap they are expensive but I do think they are a quality product. If I could pick up a used one at a reasonable price I'd do it in a minute. I did spring for their super spiffy Digital Tire Inflator, (3) chucks, 6' Hose Whip (http://powertank.com/products/sfID1/14/productID/368).
I did a DYI version. Bought a 10lb CO₂ tank new off of Amazon for $85 and found a cheap no name 150psi regulator for $50. Added a few quick connect air chucks from Home Depot and was in business.
The regulator is the weak point in my system. It's not adjustable and if I pump too much air through it does freeze up. Something the PowerTanks claim not to do. Unfortunately the PowerTank regulators start at over $200 and go to over $300 for the adjustable pro unit. :(
I've searched the internets looking for a adjustable regulator and no < $150 ones to be found. I can't even find the one I bought! It's disappeared from the nets. PowerTanks must have bought them out! :)
I do have a question for you Neil. IIRC the 2 gauges on the PT regulator measure tank pressure and output pressure. Doesn't the tank pressure stay the same until all of the liquid CO₂ is gone? At which point you are out of CO₂ so you really don't get much warning. :o I've thought about buying a second tank but don't want to have to carry it around. I just use coach air when I run out until I can get a CO₂ refill.
see ya
ken
Ken,
Away from all but my iPhone, so must be brief.
My PowerTank has no gauges on regulator.
Tank pressure is constant (PV=mRT), until liquid is gone.
Can not feel liquid in tank by "sloshing".
Amount left is very easy to understand and determine.
Empty = 17 lbs
Full = 27 lbs (hence the 10 # tank)........Dave's holds 15 lbs., so he doesn't have to fill as often.
In between, the weight change is directly proportional to the fill %
Said another way, every pound over 17 = 10% of fill
or 18 lbs. = 10% left in the tank, 19 lbs. = 20% left in the tank, etc.
Easy - peasy, as Brad says.
Neal
I've had a CO2 Powertank for as long as we have owned our coach and I really like it. It allows me to top off our tires whenever the weather changes to colder temps. Use it around the house and on the Honda too. Well worth the expense.
George
So, is your initial fill of the tires with CO2 or are you just "topping" off when needed with CO2?
Roland
Roland,
Depends on several things.
- If you can use dry air, use it. Save your CO₂ or N₂.
- If you can't tell if the air is dry or not, use the CO₂ or N₂ for the initial fill, in order to increase your tire's lifetime.
But first, be aware that the amount of moisture that is pumped into a tire upon initial fill may be less than the moisture that is introduced by the lubricants used to mount the tire.
That goop that they "slop" on the tire bead and rim is a necessary "evil", in order to properly seat the tire concentrically on the rim. Proper lubrication reduces bead damage, makes mounting easier, and will help the tire's bead fit concentrically into the proper place on the rim's inside and outside flanges (remember that both must be carefully inspected and must be concentric).
But many (most?) tire service center's cheat and don't use the proper, more expensive lubricants. Instead, they use less expensive water-based and petroleum-based lubricants. Even then, the tech's will further water these down beyond the recommended dilutions. Water-based lubricants cause both wheels and steel tire cord to oxidize (rust), while trapped petroleum-based lubricants destroy rubber over time. Sloppy service centers also often use swabs and lubricants contaminated with sand and other impurities. The solid contaminates become trapped between the tire and the rim and cause bead seating surface failure and slow leaks.
Overabundant applications of improper lubricants will introduce far more damaging moisture and contaminants into a tire's interior than pumping a tire up with moist air.Find a tire service center that uses a high-quality, undiluted, vegetable oil-based lubricant for truck tire mounting. An alternative is Michelin Bib Grease (Product Code 25817) which is an excellent example of a proper tire lubricant that can be purchased in small quantities and provided/used yourself.
How do you tell if a tire service center has dry air? Unfortunately, you can't. But you
can ask how they dry their compressed air and get a sense of whether they know (or care).
If you are in the Arizona desert and they have both pre-compressor and post-compressor filters for moisture and contaminants (that they eagerly show you), use their dry air.
If you are in Florida, it's a humid day, and they say dry air doesn't matter, use CO₂ or N₂ for the initial fill(s).
In between these extremes, you'll have to be the judge, because either will work fine. I've used both options and there is plenty of CO₂ capacity in a 10# PowerTank to fill my 6 coach tires from an atmospheric pressure start.
Hope this is of use.
Neal