Portable air compressor advice is needed

What about a Ryobi 18v P739 Cordless One Gallon Air Compressor?



https://www.homedepot.com/p/RYOBI-18-Volt-ONE-Cordless-1-Gal-Portable-Air-Compressor-Tool-Only-P739/305269932

https://www.ryobitools.com/power-tools/products/details/18v-one-plus-1-gallon-air-compressor

https://www.directtoolsoutlet.com/p739

DFord wrote:
What about a Ryobi 18v P739 Cordless One Gallon Air Compressor?

I like it!

Viair 400 here and it works great. I went with that so I can get to 110 psi and won’t have to wait all day to get there. I had a cheaper one before and it took forever just to get the truck to 80.

I carry a 12 volt in each of our vehicles. There are a little to find but I get the ones that you can set the pressure needed and it will turn off at set pressure.

12 volt compressors are a mixed bag. FIrst question is what PSI do you run in your trailer?

If it's less than 50. Most of them work. Some are faster. Some slower. Most work
IF it's over 60 Well I think my 12 volt AAA labeled box blows the car's fuse at 45 PSI or there about. That's enough for a SHORT drive (As the pressure goes up so do the amps) of course for the Motor home forget about it

Last two times I aired up a car tire (30 psi) I used an Air Dragon. I really got it for the old biclcle but it managed on the slow-leaking car tire twice before I was scheduled to hit the tire shop. Then it quit leading (Replaced tire).

My trailer and rear truck tires run at 80 psi. I check the trailer tire pressure every time we take it out and if we are taking a long trip I'll check them again during the trip. As for the truck it has a TPMS in it, so I can watch it while I drive. I plan on adding a TPMS to the trailer too. I'm looking for a small DC powered compressor that i can use to add air to the tires when we are away.

I have a small inexpensive 12v (cigarette lighter) compressor. It is fine for topping off, but when I got it, I used it to bring my tires from 21psi to 40psi. It took about 7-10 minutes to air up one tire. After that, it had to cool down for a good 30 minutes. It's fine for an emergency fill of one tire, but not for regular use. It slowed way down when it hit about 30psi. It would not be able to handle my clipper tires at 50+psi. I do like being able to set the desired psi and then letting it go - it automatically shuts off when it reaches the set psi).

For the clipper, I've been looking at the Viair also. I'm deciding between the 400P and the 300P. The 400P is about $200 (not the automatic shutoff version - which is not the same as the above; this automatically shuts off at 145psi only).

The 400P-RV and 450P-RV have the longer hoses - that may be a deciding factor for you depending on the length of your trailer. Since you will need to use the engine battery and have the engine running to use it.

The ryobi looks good until you see the weight. 141lbs is not really something to carry around. Especially compared to the 8.5 to 18.5 lb weights of the Viair.

The 88P is not much better than my cheap compressor. Might be good for a top off on a car tire, but isn't going to handle higher psi or larger tires very well.

toedtoes wrote:

The ryobi looks good until you see the weight. 141lbs is not really something to carry around.

The one linked above is 14, not 141 lb.

I bought a MV-50 in 2007 for 60ish$$ IIRC.

I disliked the screw on shrader valve connection. Had to sit there and hold it if there was any stress on the valve stem by the coiled hose, for the whole filling, to prevent it from leaking.

I wound up modifying the hose and schrader valve connector and added a 80mm fan blowing over the head.

The QC on mine was quite poor, the splices and crimps in the tailcap was very poor, no strain relief on the wire exit. The headbolts loose, the finned heatsink head only touches the cylinder walls in 3 places meaning poor heat transfer. The simple reed valves inside hardly seal perfectly.The hose and head employs some metric quick connect fitting not standard 1/4 NPT air fittings widely used in North america, but retaps easily enough for 1/4 npt. The airfilter intake holes were mostly filled with the flashing from the mold, significantly choking off the airflow.

I use mine to pump up my firestonre ride rite airbags to 100PSI. 90 to 100PSI takes as long as 0 to 90 does. My 30 amp fuse has never blown, is still original, but I never hook mine to a 45+PSI tire/airbag, then turn it on, I turn it on first.

Mine draws 16 to 19.5 amps ( depends on voltage and air pressure) and I still have the original ~6 feet of 14AWG to the internal relay, despite wanting eventually to feed with 10awg. When I hook it direct to my 40 amp DC power supply at 14.7v over 45 amp anderson powerpoles, the motor spins so much faster, compared on a 12.8v battery so 10AWG feeding it would likely reduce fill times significantly.

The MV-50 and its clones can be spit and polished into a capable reliable machines, but there could be something newer, and similar price range, which could be even better, with adequate amounts of spit and polish or more money spent on a Viair that likely does not require it.

Avoid any 12v unit with a ciggy plug. Those are for low PSI passenger car tires and owners not capable of determining where red and black clamps go.

The run times/duty cycle before overheating is certainly a factor. My improvements regarding heat transfer from cylinder and the relatively weak 80mm computer fan certainly help, but I'd question if it could fully fill a huge high PSI rv tire to 100+ PSI without getting ridiculously hot. I went through a dozen 12v air compressors before teh MV-50, but they were all ciggy plug low priced jobs, which all overheated and became noisy deflaters once they did overheat and burnt out the cylinder cup.

I went with the Viair 300P, because my trailer tires (at the time) only needed 65psi. We recently changed to a motorhome that has 22.5" tires and needs 95psi. I thought for sure I'd have to buy the 400RV model. But first, I ran a quick experiment. I dropped a tire down to 60psi and then hooked up the 300P. Expecting a struggle, I was surprised that in about 3 minutes, I was at 105psi. I don't suppose I will be changing air pumps!

I'm sure the duty cycle is better on the 400RV, but I don't expect to ever need to run this more than 5 minutes at a time.