# viair check valve



## jun_1.8T (Oct 31, 2003)

just wanna know how crappy are the ones that came with my new dual 400c? lots of people are telling me that they fail pretty quick. im in the process of putting my air ride in and wanna know your opinion on wether to change it now or just leave it. i really am in my max budget already and dont really wanna spend more but if it will really save me from headaches in the future then i guess i can dish out a few more bux for them.

TIA!


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## omeletduefromage (Jan 13, 2011)

ditch the leader lines, get some ptc fittings and smc check valves. Saves so many headaches. especially in the winter when the stock ones freeze and get stuck. 

last thing you want is the check valve to get stuck closed and you cant fill the tank and raise the car.


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## [email protected] (Aug 22, 2006)

Don't ditch the leader lines, just get leader lines without check valves and then run SMC 1/4" check valves. We sell both


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## ornithology (May 6, 2009)

[email protected] said:


> Don't ditch the leader lines, just get leader lines without check valves and then run SMC 1/4" check valves. We sell both


 Although I ditched the leaders, you could do this as well. 

Don't use the viair ones for air-ride application.


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## jun_1.8T (Oct 31, 2003)

ornithology said:


> Although I ditched the leaders, you could do this as well.
> 
> Don't use the viair ones for air-ride application.


 what did you use for the leader lines then or did you not use any at all?


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## ornithology (May 6, 2009)

jun_1.8T said:


> what did you use for the leader lines then or did you not use any at all?


 I used PTC fittings to air hose.


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## martin13 (Apr 20, 2010)

[email protected] said:


> Don't ditch the leader lines, just get leader lines without check valves and then run SMC 1/4" check valves. We sell both


 Or just unthread the check valve from the viair leader line. That way you don't have to buy a new leader line.


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## cldub (Jul 2, 2010)

[email protected] said:


> Don't ditch the leader lines, just get leader lines without check valves and then run SMC 1/4" check valves. We sell both


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## MechEngg (Jan 13, 2009)

DO NOT USE NYLON AIR TUBING DIRECTLY OFF THE DISCHARGE OF A VIAIR COMPRESSOR. 

I used nylon tubing off the discharge of my Air Zenith compressors but the viair's get ridiculously hot and will definitely melt your lines. Use a teflon lined SS braided leader line all the way from the compressor discharge to the tank (or any other source of mixing hot air with already cooled down air).


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## MechEngg (Jan 13, 2009)

cldub said:


>


 He honestly isn't just trying to sell stuff, he is giving solid advice. If you don't trust him then trust me on this one :thumbup:


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## jun_1.8T (Oct 31, 2003)

MechEngg said:


> DO NOT USE NYLON AIR TUBING DIRECTLY OFF THE DISCHARGE OF A VIAIR COMPRESSOR.
> 
> I used nylon tubing off the discharge of my Air Zenith compressors but the viair's get ridiculously hot and will definitely melt your lines. Use a teflon lined SS braided leader line all the way from the compressor discharge to the tank (or any other source of mixing hot air with already cooled down air).


 Yes...i kinda thought of that too. So i guess i just need to take the inline viair chk vlve and replace with an smc one and keep the leader line on there right?

BTW....is the inline chk vlve on the viair leader line detachable?


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## MechEngg (Jan 13, 2009)

jun_1.8T said:


> Yes...i kinda thought of that too. So i guess i just need to take the inline viair chk vlve and replace with an smc one and keep the leader line on there right?
> 
> BTW....is the inline chk vlve on the viair leader line detachable?


 Correct, it should be able to just unscrew from the leader line


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## [email protected] (Aug 22, 2006)

MechEngg said:


> He honestly isn't just trying to sell stuff, he is giving solid advice. If you don't trust him then trust me on this one :thumbup:


 He's just dishing it out, no worries.


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## ornithology (May 6, 2009)

I believe copper tubing to a PTC will work too.


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## ornithology (May 6, 2009)

MechEngg said:


> DO NOT USE NYLON AIR TUBING DIRECTLY OFF THE DISCHARGE OF A VIAIR COMPRESSOR.
> 
> I used nylon tubing off the discharge of my Air Zenith compressors but the viair's get ridiculously hot and will definitely melt your lines. Use a teflon lined SS braided leader line all the way from the compressor discharge to the tank (or any other source of mixing hot air with already cooled down air).


 Oh, I thought you used air hose to connect the tee's and elbows for your triple compressors? 

I'm thinking for me it won't be hot enough since fill time is probably max only 1min.


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## MechEngg (Jan 13, 2009)

ornithology said:


> I believe copper tubing to a PTC will work too.


 I honestly wouldn't use copper + PTC on a vibrating line, its just asking for trouble 



ornithology said:


> Oh, I thought you used air hose to connect the tee's and elbows for your triple compressors?
> 
> I'm thinking for me it won't be hot enough since fill time is probably max only 1min.


 
Yes i most certainly did, but i don't have a stupidly hot Viair compressor. The viairs get hot after about 10 seconds of running and you can't touch them after that, i can hold an air zenith in my hands for 5 minutes of running and can't tell a difference in temperature. This heat that the viairs makes will conductively make its way to the PTC fitting and the teeth/o-ring that holds and seals the nylon air tubing and will melt the crap out of it. Just my thoughts


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## jun_1.8T (Oct 31, 2003)

Ill just probably keep the leader lines and just add the SMC chk valve. 

Now the SMC comes with both sides female npt's, do i need to get one of those hex nipples to put on the end of the chk valve? Coz right now im using a street T to connect my 2 comps before going to the water trap.


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## cldub (Jul 2, 2010)

MechEngg said:


> He honestly isn't just trying to sell stuff, he is giving solid advice. If you don't trust him then trust me on this one :thumbup:


 No I know haha, Andrew is good ****. I did that face because I'm doing the exact thing :thumbup::thumbup:


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## [email protected] (Aug 22, 2006)

cldub said:


> No I know haha, Andrew is good ****. I did that face because I'm doing the exact thing :thumbup::thumbup:


  

:heart:


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## ornithology (May 6, 2009)

MechEngg said:


> I honestly wouldn't use copper + PTC on a vibrating line, its just asking for trouble
> 
> Yes i most certainly did, but i don't have a stupidly hot Viair compressor. The viairs get hot after about 10 seconds of running and you can't touch them after that, i can hold an air zenith in my hands for 5 minutes of running and can't tell a difference in temperature. This heat that the viairs makes will conductively make its way to the PTC fitting and the teeth/o-ring that holds and seals the nylon air tubing and will melt the crap out of it. Just my thoughts


 Well I'm using metal PTC fittings but it is definitely a concern now for me... 

As for the cooper + PTC I'm thinking maybe it will work if I scored the ends of the copper to make sure it doesn't slip?


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## choey (Feb 11, 2007)

Mine only lasted about 10 months just now my one has a slow leak. Just ordered some SMC for both may as well just replace them and hopefully save you the headache later down the road.


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## MechEngg (Jan 13, 2009)

cldub said:


> No I know haha, Andrew is good ****. I did that face because I'm doing the exact thing :thumbup::thumbup:


 My bad :thumbup: 



ornithology said:


> Well I'm using metal PTC fittings but it is definitely a concern now for me...
> 
> As for the cooper + PTC I'm thinking maybe it will work if I scored the ends of the copper to make sure it doesn't slip?


 Yeah you can always try, however i believe that it might cause you problems. It is the same with any type of vibrating rotating equipment that is piped to hard piping, you always put a flexible section between the vibrating part and the non-vibrating part, especially when a seal is at risk. Or else you get an extremely secure part that is vibration resistant such as a swagelok fitting that has a very good metal-metal seal instead of using just an o-ring and some metal teeth to try and grab onto metal.


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## ornithology (May 6, 2009)

MechEngg said:


> My bad :thumbup:
> 
> 
> 
> Yeah you can always try, however i believe that it might cause you problems. It is the same with any type of vibrating rotating equipment that is piped to hard piping, you always put a flexible section between the vibrating part and the non-vibrating part, especially when a seal is at risk. Or else you get an extremely secure part that is vibration resistant such as a swagelok fitting that has a very good metal-metal seal instead of using just an o-ring and some metal teeth to try and grab onto metal.


 Right on. Going to try it out to see if it works first. Have you changed your nylon hose setup? Did it melt?


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## GTI_93 (Apr 12, 2012)

I am buying my air ride kit this week with 2 viair 444c, I am switching to the SMC check valve's like I was recommended. Not totally sure what the leader lines are or if I need to change them as well...


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## jun_1.8T (Oct 31, 2003)

Ok guys...looking around for viair comps with the SMC chk valves. Mostly i see guys putting the chk valve right after the leader hose and then a PTC fitting after. Or even some guys i saw the chk valve right on the compressor head with a PTC fitting on it. Now question is...do they really get that hot that there might be a chance to melt the air hose???


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## MechEngg (Jan 13, 2009)

That picture is exactly what i would recommend. just thread that nipple into a port on your tank (with a reducer bushing if necessary) and call it a day....


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## jun_1.8T (Oct 31, 2003)

MechEngg said:


> That picture is exactly what i would recommend. just thread that nipple into a port on your tank (with a reducer bushing if necessary) and call it a day....


Thanks. I could do that but based on my layout it would be hard(check the pic). I would still need to do a "T" for the 2 comps. That is why my plan was to use a street-T for the two line and just put a PTC on the T and airline from there to my water trap which is fitted to the tank. 

My main concern is would it be too hot for the PTC that is on the street-T and melt the airline?

Thanks!


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## Dodgeman (Nov 26, 2020)

Hate to bring up an old thread but I have similar issue. Viair 480c only about 14 months old. They won’t warranty the check valve. So I checked around and my setup uses a 3/8 line which means check valve is a 3/8 female to 3/8 male. The only smc check valve I could find was this one part #


AKB03B-N03S
​

here’s the link.





SMC AKB03B-N03S Check Valve, Ak, Akm, Akh, Akb | Airline Hydraulics


AKB,




www.airlinehyd.com





will this work for my application? It’s 3/8 NPT female to male. The only part I don’t understand is they call it a one touch.

I’ve also got a bad pressure switch which is an all in one pressure switch and relay from viair. My other one failed too which was on my 450c. After changing it, it worked for years. It still works same with the original compressor. Just upgraded to twin 2.5gallon tanks and 480c compressor. so had to upgrade to the 200 psi switch. So sad how viair has gone down hill with quality of check valves and customer support.


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