Quick version: can 43 cold psi fail a valve?


Last night I had a valve go bad on my SSR GT3 19x10 wheel. when i undid
the cap to check tire pressure like i always do every weekend, the air
started leaking out slowly.

i pressed the center pin a couple of times and even rotated it half turn
with a long nose to see if it would re-seat itself, but it's still leaking.
the leak stops as soon as i screw the cap back on. :impatient

I had a brand new pair with tires in my garage so i swapped out the 2
rear wheels.

Now comes the question...
Ive had valve stems (2times) fail on Kosei wheels in the past where the
seal around the base of the stem broke, but ive never had the valve fail
inside like this.

The only thing i did differently this year is that i pressured up the tires
to 43psi when the cars were hibernating. i seriously doubt 43psi was the
root cause of this failure cause tires can reach 43psi on a hot summer
day. im also very gentle with the valve not to move it around too much
while checking pressure or adding air, nor torque down the cap that tight.

What do you guys think? Minihune? the other 3 valves were fine, so
are the SSR's on my MCS that were also at 43psi for a couple of weeks in
Dec.

anything i can do to prevent this on the other tires? im going to set it at
38psi when hibernating again like ive been doing the last couple of years.

 

Sometimes valve cores just "go".

Also - get a valve core tool and re-tighten it - I know you said you used needle-noses, but it's hard to ensure you got it right without the right tool...

Most leaky valves in my experience are actually loose cores...

 

In the past 10 years, on a variety of vehicles/wheels/tires, including my motorcycle I have had the valves split away at the mounting base, leaving me flat as well as the leaky cores. at least 5 of each accross a fleet of 5 vehicles. always annoying, but better than finding a screw in the sideall. My opinion is, the valves and cores themselves, like everything else in todays world, are made from crappier materials to lesser standards. It has happened too many times to me to be anything else.

 

How cold was it in your garage? Like all things man-made, there may some variation in size in the various valve cores you have, and this one was just undersized enough to let air leak when the seal contracted in the cold.
Or, I might be full of ****!
Doubtful that 43 lbs would cause a leak. I haven't seen different pressure ratings on cores, and some SUV/truck tires run 60-80 lbs.

Swap it out. Cores are cheap.

 

can you show me a pict what it looks like? is that something i can get
at Sears?

Central Coast Coopers - yah, ive had valves fail but never on SSR wheels.
but you're right, i think the up and down on psi probably killed it. im going
to keep it at 38psi when i store it from now on. the seal might have
developed memory from it being set at 36psi most of the time?

my garage temp is usually about 38F-50F. i was letting the air out before i
drove out. ...

dang it, just frustrating cause somethine else i need to do, ya know.

 

Any auto parts store, or probably any filling station, or the auto dept in any Walmart, Target, etc. should have them for a couple of bucks. Just ask.

Most are little T-wrench type things with a a couple of prongs that engage the core.

Typically the cores in car tires are the same as in Schraeder-valved bicycle tires - which routinely hold over 100psi...

 

super! thanks for the info. ill give that a shot first
and if it still doesn't work, i'll take it over to tirerack to get it
repaired.

 

BlimeyCabrio- i looked closely at the valve and used my super slim needle
nose pliers and turned the valve's slot thingie inside about quarter of a
turn. wat do you know, the leak stopped!

thanks for the tip, blimey!

im going to go find that tool now.

 

That. Should. Do. It.

1/4 turn is just about right for the kind of leak you were describing.
Glad you had some pliers small enough to get in there.
Get a tool - they're nice 'cause they're a particular size that doesn't encourage you to over-torque the core, which is bad.

 

I usually equip the spare with a valve cap that has a core tool on the back of it, but this car has no spare, so I just leave the cap-tool and extra cores in the flat repair kit. There's another reason cores may leak and that's if a piece of dirt gets on the seat. I use a pipe brush then.

I've even equipped 2-liter soda bottle caps with schraeder valves and used a bicycle pump to keep the soda from going flat

 

Valve cores by their nature seal tighter with increased pressure. If you find that you are experiencing leaks, it can be caused simply by a bad/substandard valve core, but sometimes this can be caused by a dirty air supply or debris inside the tire. This can jam a core open or damage it, causing a leak.If you suspect debris inside the tire, remove the core and repeatedly inflate and deflate it (with clean air) with the stem at the lowest position to help clear some of the dirt out. Many oilless/tankless tire inflator/compressors often have little or no filtering and can introduce debris in the air stream. If using a tank-style compressor, make sure to drain the tank regularly of water and debris, and add ain in-line filter at the tank outlet.

If you use the air pump at the local gas station, anything is possible.

 

^^ thanks for the tip GreatBear.

i was playing around with my old spare Kosei valve yesterday to
understand the construction of the core. i can see how the seal
would seal even more when there is higher pressure.

therefore, 43psi cold for hibernating cars should not be an issue.