inflating tire, cubic feet of air in tire and in air tank and psi
- Thread starter tony326
- Start date
update
i found a air tank 8x24" with frame mount off a f-450 truck at pick-n-pull for 15 dollars. i will install it near the double side door with hose and regulator, i went to autozone look at air pumps and found duty cycle too short and fill time too long. i didnt want to be on road side for hour just to fill a tire, not wanting to spend big bucks for a emergency tire filler, any suggestion on a pump that will fill the LT235/75r16 tire to 85psi and not take an hour and overheat looking for the best bang for the buck air compressor.
http://amzn.to/2crfPQd
IMO just get one like luthj already posted. Best bang for buck. I've had one like this for a decade. And it does not take an hour, takes just moments.
IMO just get one like luthj already posted. Best bang for buck. I've had one like this for a decade. And it does not take an hour, takes just moments.
v_man
Explorer
I went through an "I-need-onboard-air" phase for awhile . I was looking to mount a York compressor and run it off my engine crank . So glad I didn't go that route . Tons of work , extra plumbing , and hours spent researching it online .
It is cool in concept , but even with something like a York setup , you still need to have your vehicle running to create air . A small electric compressor is my choice now , C02 just not worth the hassle ....
It is cool in concept , but even with something like a York setup , you still need to have your vehicle running to create air . A small electric compressor is my choice now , C02 just not worth the hassle ....
Robert Bills
Explorer
I have had many different onboard air systems in various vehicles through the years, including York and Sanden belt driven systems, hard mounted 12v compressors, and portable 12v compressors including the ubiquitous MV-50/MF-1050. I recently threw away a MF-1050. These are cheap but they don't last, tending to suck reed valves at the most inopportune moment. I replaced the MF-1050 with a Viair 400P, P/N 40043, which in my opinion is currently the best value for a reliable portable compressor kit capable of filling tires up to 35" in diameter and also high pressure RV tires. I purchased mine from Amazon for $171 with free shipping. Although it is a 33% duty cycle compressor, the flow rate is sufficient to fill 4 33" tires from 15 psi to 38 psi in less than 10 minutes, long before duty cycle becomes an issue. If you prefer a hard mount compressor, the 400 series compressor is P/N 40040. Check the fill rates listed on the Viair website to see if it might work for you. http://www.viaircorp.com/400C.html
Just as with nearly everything else in life, you get what you pay for with compressors. There are good values, and good compressors at reasonable prices, but the terms "cheap" and "good" seldom belong in the same sentence when describing 12v compressors.
Best of luck.
Bikersmurf
Expedition Leader
Traded beer for one of these...
http://www.homedepot.com/p/TITAN-OF...rtable-Air-Inflator-TitanMaxAirComp/205891678
so far seems good. I've not mounted a spare... so have to keep the 6 wheels inflated.
Rated output of 160 LPM or 5.65 CFM (at zero PSI)
Maximum voltage is 13.8-volt, maximum amp draw is 45 AMP
Maximum restart pressure is 150 psi
Maximum operating temperature is 140 degree F, minimum temperature 67 degree F
AIRING up times: 32 in. tire - 10 psi to 32 psi = 1 minute 30 second 33 in. tire - 10 psi to 32 psi = 2 minute 35 in. tire - 10 psi to 32 psi = 2 minute 45 second 2.5 gal. air tank - 0 psi to 125 psi = 1 minute 20 second
I trust the onboard air on my FJ40 more... but I don't Wheel the Ambulance so the electric does the job. The listed fill times don't seem any better than the Vivair despite having a higher rated CFM... makes you wonder.
Quality isn't awesome, but it works well... and the compressor and a decent sine wave inverter for a 24 was too good to pass up.
http://www.homedepot.com/p/TITAN-OF...rtable-Air-Inflator-TitanMaxAirComp/205891678
so far seems good. I've not mounted a spare... so have to keep the 6 wheels inflated.
Rated output of 160 LPM or 5.65 CFM (at zero PSI)
Maximum voltage is 13.8-volt, maximum amp draw is 45 AMP
Maximum restart pressure is 150 psi
Maximum operating temperature is 140 degree F, minimum temperature 67 degree F
AIRING up times: 32 in. tire - 10 psi to 32 psi = 1 minute 30 second 33 in. tire - 10 psi to 32 psi = 2 minute 35 in. tire - 10 psi to 32 psi = 2 minute 45 second 2.5 gal. air tank - 0 psi to 125 psi = 1 minute 20 second
I trust the onboard air on my FJ40 more... but I don't Wheel the Ambulance so the electric does the job. The listed fill times don't seem any better than the Vivair despite having a higher rated CFM... makes you wonder.
Quality isn't awesome, but it works well... and the compressor and a decent sine wave inverter for a 24 was too good to pass up.
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Mwilliamshs
Explorer
Unless there's a standard specific to these little compressors, duty cycle means the portion of a 10 minute period a machine can be run under load. 33% = 3:20. This is the way pumps, compressors, welders, etc etc etc are rated.
Bikersmurf
Expedition Leader
I believe the Titan (also sold as SmittyBuilt) has a 100% Duty cycle by this definition. Instructions indicate It can be used for 40 minutes continuously.
Edit: Did some more reading... their definitions are different. 40 minutes @ 40 psi @ 75 Deg F. Looked for a rating at 100 psi but couldn't find one anywhere. It seems to do the job well for me, and reviews are very positive (even from those running 35-37). To save a trip to the service station... I'm sure it'll handle my 225/75R16s just fine.
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Robert Bills
Explorer
Thank you for the generalization, but the definition of duty cycle for air compressors is "the amount of time a compressor can be operated in a given time period at 100 PSI and a standard ambient temperature of 72° F." It is sometimes expressed in 10-minute increments, but not always, and it does not mean that a 33% duty cycle compressor can only be run 3 minutes and 20 seconds before it must be allowed to cool.
Viair is specific about time of use and cooling time for their 33% duty cycle compressors - 20 minutes of use then 40 minutes off to cool. See http://www.viaircorp.com/tech.html Note also that duty cycle is calculated at 100 psi, not the 35-60 psi typical for passenger and truck tires or the 85 psi typical of high pressure RV tires.
Bottom line, the Viair 400c compressor with 33% duty cycle and flow ratings of 2.62 cfm @ 0 psi, 2.01 cfm @ 40 psi and 1.65 cfm @ 80 psi is plenty for airing up all four tires on one vehicle because the tires will be back up to street pressure long before the compressor has run 20 minutes. It is more than sufficient for airing up one flat tire from 0-85 psi. Admittedly, it won't air up an entire group's tires at one time or run air tools, but that is beyond what the OP and most offroaders need.
Bikersmurf
Expedition Leader
I've always run a tank with onboard air. That way it's always ready to go without any top ups. With that truck I'm not worried about needing to be running if the tank gets run down... If it won't run I've got bigger problems than a flat tire.
Is anyone here a Scuba Diver? You can get a small 19 cubic foot pony bottle and fill it to 3000 psi. (Standard scuba pressure). I have friends that use this to fill their vehicle tires. With that pressure you would be totally good. Also, you have enough air for many problems. Probably couldn't fill tires from empty, but should be good for topping them all off. Also, a standard scuba cylinder is 80cu ft. Soooo that to 3000 psi and you could fill your tires from empty. And theyre not that big.