OBA -> On Board Air Mega Thread & BS

I would tend to think it's not leaking out of the compressor because I have a check valve downstream of the compressor. Unless the check valve is bad.

 

If you store air in a tank it needs a check valve. Pumps definitely leak back pressure. The cylinder “valve” can be as simple as a flexible metal strip over the intake port. It works as a one-way port but doesn’t really seal very well. A spring loaded check valve will take care of that.

 

Have you checked the Schrader valve? They can leak too. Otherwise it’s going to be either the ptc connections or the tapered pipe thread connections.

 

When I installed my OBA system, I used brass compression fittings. Had a good sized leak that would make my compressor blip every 4 to 5 mins. No air tank (yet).

Drove me nutz!

After extensive leak checking with soapy water, I resorted to systematically capping each fitting starting at the pump outlet. Worked my way through the system. Turned out to just be a compression fitting that needed one more "ugga dugga" and all was good from there.

Now it holds solid for weeks.

 

Just an in general FYI, when using compression fittings for soft tubing you’re supposed to use nylon compression sleeves along with brass tube inserts instead of the brass compression sleeves supplied with each fitting.

 

You are probably right. The 3/8" plastic air hose I am using is quite rigid.

$22 TAILONZ PNEUMATIC Air Line 3/8" od Blue Pneumatic Nylon Tube 32.8ft Air Brake Tubing Nylon Hose

https://www.amazon.com/dp/B08HQST6FD/?coliid=II381UJLSA7KE&colid=2X0EZYTFDNQHS&ref_=lv_ov_lig_dp_it

It came in a tight coil that I warmed up in the oven to get it to layout mostly straight, and then pinned it to the yard and hosed it down with the garden hose.

After putting this system together and getting everything leak free, I think I might switch out the connection points to the push lock style for tool free maintenance. The compression fittings are kind of a bear to deal with in tight proximities under the hood.

This system should get me through this summer and then I'll be looking at changing things out.

Otherwise having air at the front of the truck and at the rear bumper is a game changer for sure!

 

I don't have a Schrader valve in my system.

 

I have it as an alternative to the compressor for filling the tank and for those without a tank it’s the most common fill port for air bag systems. You’ll probably need to use a more persistent soapy mix. It could also be a pinhole in the tubing itself. Unless you submerge the entire kit it will be hard to locate. Schrader valves come in handy for that kind of testing. I’m in the midst of building up a manifold to use air cylinders instead of linear actuators and the more connectors you have the more leaks are possible but I can charge the whole thing including 50’ of tubing and dump it in a cooler. 2 of 6 ball valves had cracked seats where the 1/4 mpt connectors screwed in. Some of the pipe thread connectors took more than one attempt to seal since under magnification the threads were ugly.

 

Quick question-- Reading a couple pages back it seems like some of you are leaving your system charged with air full time even while the vehicle is off. I always thought that leaving any air compression system full of air was terrible for fittings over time. They are constantly holding pressures. Similar to a garage air compressor for running tools. I always bleed out my systems after they been used and let them sit empty until the next use.

There has to be a way to isolate the tank where only the tank would be holding pressure and keep the lines empty. Now you guys have put me on a path I'm not entirely ready for.

 

The fittings are designed to hold pressure. They don't have a duty cycle, so being pressurized constantly isn't going to hurt them. The reason home owner grade compressors want you to vent them is because is condensation. The tanks are steel, so the condensation will rust them out from the inside overtime if they're left sitting.

 

If you feel the need you can install a 12v ball valve at the tank output. They make them in different wiring configurations for use with different switch types and they come in handy for isolating different parts of the system. I have one installed.

 

I’m pretty nooby at this, but if I’m installing an Aircomp that I want to run off the blue sea fuse box can I use two circuits ran to one 80a relay and then one wire running to the aircomp from the relay? It’s a Viair 400p, so I know it needs just above what the blue sea provides on a single circuit. I just want to make sure it’s one to have two circuits go into one at the relay as opposed to running it straight from the battery.

 

That would work, but you'd be better off running a wire straight from the battery or system circuit breaker (if you're running one) with an inline fuse.

 

I know it sounds crazy but I just think having the wires leave my aux fuse box would appear like a cleaner install. Besides simplicity are there other advantages of coming straight off the battery?

 

Only 1 fuse for the system vs 2 with what you're proposing. Also, you have no way of guaranteeing that the current draw from the two circuits will be the same. If one side blows before the other, you're going to get a massive current spike through the second side which will blow it as well. If you're making your own cables from the battery to the Blue Sea, it would be easy enough to get a slightly larger gauge lug and crimp in both the wire for the Blue Sea and the compressor. The sleeve them together, so it looks like one cable.

Like I mentioned, you're going to be running a circuit breaker, you can just pull a second wire off of it for the compressor. You can mount an AMI/MIDI or ANL fuse holder on your panel for an integrated look, instead of an inline fuse holder.

 

Those are pretty valid, I think I’m convinced.

 

I know this thread is more about the air install than it is the wiring part but if I have a relay with 12awg wire coming out of it spliced to 8awg for the long run to the compressor will that cause issues?

the relay in question: 4-pin 80/60 AMP 12V DC Waterproof Relay with Harness - Heavy Duty 12 AWG Tinned Copper Wires, 1 Pack SPST Bosch Style Automotive Relay for Marine Boat Fan Light

$10 irhapsody 4-pin 80/60AMP 12VDC Waterproof Relay Kit, SPST Automotive Relays, Pack of 1

https://smile.amazon.com/dp/B08D8T9X9R/ref=cm_sw_r_cp_api_glt_fabc_KPN8VX7DEF4S2PKWP0NX

 

You’d be better served to pull the two #12 wires(pins 30 & 87) and have only #8 from terminal to terminal. The awg12 isn’t rated for 60A no matter how short the run.

 

Are there any other options beside arb that are sealed that people are running on second gens. I want to outfit my gfs second gen but she’s not going to use it all that much and doesn’t want to pay for the arb. Let me know

 

Vair is another decent choice.