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Portable tire inflator?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by PriusRos, Aug 13, 2006.

  1. PriusRos

    PriusRos A Fairly Senior Member - 2016 Prius Owner

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    Well, today was good weather and the first time I had a chance to try out my new Craftsman 12V inflator.

    First, I detached the digital gauge from the unit and went around measuring each tire with both the digital gauge and the Accutire dial gauge I bought at the same time. The measurements seemed pretty close, but because the dial gauge only measures in 1 psi increments and the digital in .5 psi, it was a little hard to tell whether they were an exact match. I was surprised that my readings were so low (around 33.5-35 front and even less in the rear) because I thought I had inflated the front to at least around 37 about 2 or 3 weeks ago with the inflator I had returned (mainly because I couldn't get a decent reading on the gauge!).

    After making all the measurements, I reattached the gauge to the unit and plugged it in to the "cigarette lighter" socket. I read the instructions carefully. Attached the air hose to the first tire valve. Got the reading on the gauge. I wanted to use the automatic shutoff mode so I pressed the + button to set the desired pressure. Nothing happened. The reading wouldn't change, no matter what buttons I pressed. I thought, looks like I am going to have to return this one as well, but let's see whether it will at least pump air. So I turned the switch on. Nothing happened. Well, that's a bummer -- damn thing doesn't work at all! :angry:

    Then it struck me. *DUH*. I forgot to turn the car on. No Power.

    Well, it worked pretty fine after I made that little adjustment. (Actually, it still doesn't quite make sense to me that I would need power to preset the gauge when the gauge reading runs off its own battery, although I do realize I need power to pump the tires! :rolleyes: )

    As others have reported, using the presets, it shuts off when it thinks it has reached the preset PSI, which is 2-2.5 psi less than the actual preset amount. But when it shuts off, it's easy to take the actual measurement again, then add more. Although I set the preset 2 psi above the target amount, it would still sometimes be .5 short.
     
  2. Kizzy

    Kizzy Member

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    My experience with the Craftsman air compressor (w/digital gauge) has been similar. Using the auto preset, I find that an additional 1 PSI is needed to bring the tire up to the desired pressure. I usually also need to add .5 PSI on top of that, to account for the air that's typically lost when removing the nozzle (it fits on the tire valve pretty tight, so some air is lost when removing it). So, in order to inflate my tires to 38/36, I will inflate the front to 39.5 and the rear to 37.5 on the compressor. After turning off the pump and disconnecting the hose, they will be right where I want them.

    Other than that, it's a great unit. Very compact, and I do like how all of the pieces fold away neatly for storage. The digital gauge seems consistent, and from other posts I've read, is also fairly accurate.
     
  3. drees

    drees Senior Member

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    How noisy is the Sears/Craftsman compressor/inflator? I have a cheap 12v unit now which is pretty annoying to use it's so loud, having the auto-shutoff feature would be very handy.
     
  4. Kizzy

    Kizzy Member

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    I doubt any of these 12v units are very quiet, but the Craftsman isn't as loud as some of the others I looked at. To get a compressor that's quiet, you'd probably have to look at the models that are used for airbrushing, and they tend to be quite expensive. But the good news with the Craftsman is that if you're only filling up a few PSI or so, it works pretty fast, so at least the noise isn't on for too long. Today, I increased my tires about 3 PSI, and for each one that took maybe 15-20 seconds. Sure beats going to the gas station, where the gauges are inaccurate and they charge you $.50 or more to use the air hose. :)
     
  5. drees

    drees Senior Member

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    Thanks for the feedback. 3 psi in 15-20 seconds is very fast compared to the one I have now. It probably takes a minute per psi which makes the racket it makes that much more unbearable when you need to sit there watching the gauge. Sounds like the Sears unit will be much better in all areas.
     
  6. patsparks

    patsparks An Aussie perspective

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    I have a $99 direct drive air compressor in the shed I can use for spray painting and to drive an air wheel nut runner for servicing. The compressor came with a tyre inflator tool but I use a good gauge.
     
  7. birdsquared

    birdsquared New Member

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    I just picked up this little unit from Canadian Tire for $13 and it seems to works just fine (added about 5 psi in under a minute) (though the built in gauge is WAY off - it says 52 when my Accutire says 40.5). It's extremely easy to use, though the hose attaches to the tire with a screw on attachment - which means you get a very good seal, but it bleeds a tiny bit when you unscrew it. It fits very nicely into the side pocket at the left of the hatchback storage area, and though noisy, is quite light.
     
  8. alanh

    alanh Active Member

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    FWIW, don't get the rechargeable one. I made that mistake. The hose where it exits the box gets extremely hot, to the point where the rubber starts to smell burnt. A number of reviews on the Sears site indicate that the hose is prone to breaking, and overheating is probably why.
     
  9. a priori

    a priori Canonus Curiosus

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    Now that this old thread has been "re-opened" . . .

    I'll add that I picked up the Sears charger discussed in earlier posts. It works quite well. I like the digital read-out, the ability to pre-set the PSI, and the size. Most of all, I like the way it quickly and neatly packs up. The cords are nicely sized to wrap around the body of the compressor, and all of the attachments are easily held in place on the compressor.

    It is there when I need it and is always available for anyone who needs to add some air.
     
  10. kpeter

    kpeter New Member

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    Ditto for the Sears inflator. Based on this thread, I bought one. I agonized a bit since I worried that I should really be getting a decent compressor, and since I had earlier purchased a $15 12 volt inflator that was a piece of junk.

    The Craftsman does a decent job topping off tires, though it was not as fast for me as for some. Getting a tire from 32-40, for example, took a few minutes. But it was not overly loud, seems decently put together, and stows well. I'm impressed enough that I will buy a second one to carry in my other car.

    By the way, I also bought an EZ-Air-Digital gauge (made by Accu-Gauge).

    Tire gauges

    You fill the air right through the gauge, so you can continuously monitor the pressure as you pump. (The Craftsman's own gauge does this, but I don't trust it.) It also has a bleed valve. This gauge always read about 2 pounds lower than the built-in gauge that came with the Craftsman. It seems rugged and I love the easy way it clips onto the tire stem.
     
  11. Deaconblues

    Deaconblues New Member

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    Well, I was going to start a thread regarding finding a good 120v inflator, but it appears that the Sears 12v might be the way to go :p

    Checked my tires (first time since I bought the car since it's been very cold here and I'm numbingly lazy when its cold) and they were all at 33 psi :mad: Refilled them to 38/38 and will see how it goes.

    BTW, I bought a "professional" tire gauge made by Beto, and it's the best gauge that I've ever owned. Has memory points, and ability to bleed with "real time" pressure.
    AutoSport Catalog - Professional Digital Tire Gauge 800-953-0814

    As always, I really appreciate all of the great info that I receive on this forum.
     
  12. birdsquared

    birdsquared New Member

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    You probably want to go to 40/38 or 38/36. Even the Toyota manual (and the sticker inside the driver's door suggest an extra 2 PSI on the front tires to support the extra weight of the front end.
     
  13. Rokeby

    Rokeby Member

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    FYI, some interesting info on non-digital tire gauges here: Tire gauges

    Accurate to lowest claimed value only close to center of range, etc.

    Although info not at above site, on numerous sites digital gauge manufacturers claim they are accurate to stated values across full range.
     
  14. edthefox5

    edthefox5 Senior Member

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    I saw that one you got at Sears and I went and got one too. The $ 20 one that works off the cig lighter.It works good. Has a nice long 12 volt cig lighter cord and it didn't blow the cig lighter fuse as I expected. Works good for the casual fill up. I run 43-40. About every 5 days I use it now since its cooler. I just put it on the back seat floor as never use the back seat and have the seat back down all the time anyway.Only thing weird with it is the connector that attaches to the tire valve will not lock onto the valve without really forcing it which I have yet to do so I just hold it to the valve. No big deal. Thank you.
     
  15. TeamWenz

    TeamWenz New Member

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    I have one i bought at Walmart. It has a battery in it that you can recharge. Also has a flashlight for aiming at the wheel when adding air in dim light. The charge last a long time and I think I paid $30 for. It works great, It's blue in color. If there is a selection to choose from find the biggest one that mentions you can use it on truck tires.
     
  16. Rotorhead

    Rotorhead New Member

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    This is the best gage I've found - Tire gauges I've tried a few of the 12V compressors and have yet to find one that isn't loud and slow. Still looking.
     
  17. birdsquared

    birdsquared New Member

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    I just got the EZ Air (as in the link from Rotorhead just above), and it is great - while it is analog - it is very accurate - (matches my digital Accutire gauge exactly), AND I can pump through it with my handy dandy 12V inflator. The EZ Air has a very handy snap on/snap off connector to the tire, and threads at the other end, so I screw on the end of my 12V inflator. If it needs air, I just turn on the 12V for a handful of seconds, and then when I turn it off, I get an immediate accurate reading. Couldn't be easier or more convenient. I almost feel dumb for having bought the Accutire, now - though it stays in the console, while the EZ Air plus inflator stays in the rear side pocket under the trunk mat.

    I can't recommend this combination enough - accurate tire measurement with immediate top off ability, in a small light package...
     
  18. jackalope

    jackalope Member

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    I just use a bicycle pump. It does give you a bit of a workout but does the trick for me.

    I am not sure how accurate the gauge is for low pressures so using proper gauge is probably a good idea.
     
  19. ny biker

    ny biker Member

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    Just curious - how much of a workout? Is it harder than pumping a road bike tire up to 120 psi?
     
  20. jackalope

    jackalope Member

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    Maybe a bit more work than for my road bike. It is a lot lower pressure but then again a lot more volume x 4 tires! It takes a lot more pumps to go up a few pounds with such large tires.

    Even at 15F in the garage I remove my coat by the 4th tire :)