Air Compressor Woes... Viair blowing hoses

[Dave Bennett]

My Viair 400C works great... too great. It keeps blowing hoses right at the connection between the leader hose and the hose that runs to the bulkhead fitting. No air tank just a simple setup using the ARB air chuck that SE sells.

I've tried the commonly available yellow coil hose and the rubber 3/8 air hose both rated at 125psi, but they dont hold up to the compressors output.

I guess my next option is the hard plastic DOT air line. Is there anything else I'm not thinking of?

 

[goodtimes]

Relief valve?

Is the chuck one of the constant flow varieties (air always flows regardless of it being hooked up to a valve stem or not)? If it isn't -- it should be.

 

[gwhipp]

I have ARB Tire Inflator with Gauge from SE. It is not a free flowing chuck. I would add a Tee connector and a pressure relief valve. This way you are not always pressurizing the lines. Once they reach a max pressure, it will open the valve.

This would work, but I would get something with an even lower pressure.
165 psi Blow Off Valve Maybe 125 psi.

 

[MotoDave]

Is the hose coming off of a barbed fitting? Or is the hose actually bursting/splitting?

Not sure how far this connection is from the compressor, but I've noticed the hose right at the sompressor output gets extremely hot, to the point I'm thinking of having the first few feet of hose be copper tubing, then adding my regular quick disconnect to the rubber hose.

 

[allnew2me]

You are blowing the hose because that is the only place to vent in your system. You can't use an air compressor without a tank unless it has a bypass, or blowoff on it. When the compressor is on that air has to go somewhere, if you don't give it a path something will give as you have noticed. You can use it as you are as long as it is connected to a tire, but the air chuck restricts the passage of air when not connected to a tire valve and the pressure is building up until it blows the hose off.

 

[CharlieV]

I also have the same setup mated to run with two ARB's (through a set of pressure regulators), but I haven't had any problems. I know all the fitting are the plastic push in "new style" that are all the rage these days. If you're blowing your hose out of the fitting Vs. blowing a hole in the hose, I'd suggest switching to the tried and true traditional brass air fitting with an inner sleeve and a collar.

After re-reading your initial post, why is there no tank? They come with a 2.5 gallon reservour, no? You must have a regulator somewhere because ARB's are only designed to handle 90psi if I'm not mistaken. For an actual air line to fill tires I use a 25' length of rubber 3/8" shop air hose. I like it much better than those coil hoses.

 

[Token]

Had the same issue with the the large Masterflow unit.. Ended up with a 2000psi hydraulic line for a leader.. Gets hot as all get out, but it stays on the compressor fine..

Fittings on the end of the 1/4 line are same as 1/4 NPT air fittings, so it worked out pretty good.. You'll need a rotary cut off wheel to get a clean cut on the end going to the compressor and then drill the line out just a bit to get it over the barb (hydraulic line does NOT stretch).. Might find it helps air flow to drill the end of the fitting on the other end a bit as well..

 

[nwoods]

As stated, if you are doing anything that prevents air flow while the pump is on, then it will blow. Or, get an expansion tank with a relief valve.

 

[Dave Bennett]

Thanks for the replies.

I'm thinking I need a T with a pressure relief valve and some heavier line (it is blowing the line near the leader, not blowing the line off the barb).

The compressor is rated at 150psi max so some 200psi line and a safety valve should be the answer, I'm not running a tank as I wanted to keep it simple but maybe that's what I need?

 

[Desert Dan]

It may be getting too hot!!

 

[rezdiver]

wherther you have a tank or not, ALL compressors need either a relief valve or a pressure shutoff solenoid. although the compressor can handle high pressure, by letting it deadhead, you are shortening the life of the compressor, and something will let go, luckily it has been your hose so far.

also as the pressure increases with nowhere to go the hose end and fittings get very hot, this softens the hose allowing it to slip off the fitting. you can fit hose as strong as you want doesnt matter if its 200psi rated or 20000psi, the compressor will break if it has nowhere to go, you will either burn out the motor or break the compressor head.

 

[goodtimes]

. . . or use a constant flow (non-sealing) chuck.

 

[monele]

Get a brass T fitting and wire/plumb this in:

http://www.4by4connection.com/12volpresswi.html

Problem solved.

 

[MotoDave]

Ah, didn't realize you werent using a pressure switch. I have that same pressure switch wired into my onboard MasfterFlow MV-50 setup, and it works perfrectly. I don't have a tank either, just a quick disconnect at the compressor for a regular air line. When I turn on the compressor it runs up to 105 psi and shuts off, then when I connect the air chuck to the valve stem at the tire the pressure drops and the compressor runs as long as its connected. When I disconnect it to change tires, again the compressor charges up to 105 psi and shuts down.

 

[geo.greg]

I don't think the problem is blowing hoses, but that the pump continues to pressure the system beyond max psi. I believe that your compressor requires a shut off switch that turns off the compressor at 150 psi. I didn't read anything about this in your system. Quote from website
"All VIAIR “C” model compressors are intended to fill air tanks. They are not equipped with an ON/OFF switch or pressure sensitive shutoff device of any kind. The use of a pressure switch and relay are recommended and required."