I've had three failed valve cores on the bus in the past couple of months. They all slow leaked or failed to reseal when I checked the pressure with my gage.
These are the red seal type I get at WM by the package.
It may be that these are not pressure rated high enough for bus tires, I didn't notice any pressure rating on the package. Or it may be that they are just cheap! The main difference I noticed is that the seal is red and the core is shorter than valve cores used to be. I have no idea if length has anything to do with the rating?
This is strange to me because I don't remember having valve cores fail but a few times over many, many years of owning vehicles of all types.
Has anyone else been having this problem or is it just me?
Must be the melamine.
I know this is a long shot but I had the same thing happen with a pack of wally stems, I had 2 of them fail, something I hadn't had happen before, I went to napa and got new ones and they are still holding nicely.
The cheap "chinese" valve cores are not rated for the pressures or heat generated by bus and truck tires.
I thought someone told me one time that the color is the rating. Red is for 32 psi as I recall.
You need to go to a truck supply place and get real valve cores made for truck tires. They are different.
There are rubber seals, synthetic rubber seals, nitrile seals and plastic seals.
which is based on pressure, temerature and use.
Thanks to all for responses.
I thought about calling the nearest truck tire place and ask them where they get their cores.
I highly suspect that once I stop using the red ones my problem will be solved.
Cody,
Were the ones from NAPA long or short?
Dave,
I don't know that the cores are Chinese. They may be but that alone probably doesn't automatically make them bad. All my bus tires are Asian as probably half the tires on the road are now.
Which of rubber seals, synthetic rubber seals, nitrile seals and plastic seals are truck/bus tires supposed to use?
Dunno fur sures, but would guess (probably wrong also) that it has to do with the application...automotive, light truck, heavy truck, farming, industrial, north pole, airplane, space shuttle, warp driven shuttles, (do they have tires?) or just befuddled. Happy New Year. HB of CJ :) :) :)
This is sort of related...I went to Advance Auto, bought 4 valve stem extentions for Dianne's pickup, one leaked...none would let me put air in the tire from a standard chuck. Cheap Chinese crap???????
Jack
As far as I know, get your valve stem cores rated for the correct pressure, for an on-highway tire.
Don't fool around, you want all of them good for as high as the rating on the tires.
Walmart is not a likely bus chassis parts supplier... Get familiar with your local heavy jobber. You'll be pleasantly surprised at what is available and at what cost and what quality.
happy coaching!
buswarrior
Valve stems are not the place to go cheap! Go to a truck tire shop and buy yourself some good metal stems. I just bought one at the T/A truck stop for $5. Your tires cost you $200+ each. There is no need to ruin one or cause major damage to the bus by buying a 50 cent valve stem.
All that mess said there is a HUGE difference in valve stems. I came home one day to a flat on my 5th wheel...huh I said. I didn't have time to fool with it so I left it. I came back a week later...now I had 2 flats. My first thought was who the He&* is messing with me. As I looked and tried to air up the tires I found the the valve stem were all delaminating at the base. I aired them up the best I could and took off for the tire shop. when I got there they explained I had "low pressure stems" on there. Seems the low pressure stem have more rubber and less metal. on the high pressure stems the screwthread extends down near the bottom. Hard to explain but easy to see if you had them sideXside.
All that said both those stems should not be used on a bus. The correct stem is all metal and has a nut on the outside of the rim.
Here is your standard low pressure
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi15.photobucket.com%2Falbums%2Fa392%2Fletz4wheel%2Fsnap-rubber-valve-7D-thm.jpg&hash=6e09a21ad11506b54ec654b87170b3b0a3e01f60)
High pressure
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi15.photobucket.com%2Falbums%2Fa392%2Fletz4wheel%2Fhigh-pressure-snap-G24120HPV-thm.jpg&hash=a91f58f94ee64a3046de1ad72edf7dd5928cbe9c)
Truck and Bus
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fi15.photobucket.com%2Falbums%2Fa392%2Fletz4wheel%2Ftruckbus.jpg&hash=2d7717334b47bcd8644bf84f8892a8e395515450)
Gus,
Do you by any chance have equal sand in your tires for balancing them? If so we have had the same problem. The sand gets caught in the stem and then it doesn't seal.
JAT
God bless,
John
Quote from: John316 on January 01, 2009, 09:06:39 AM
Gus,
Do you by any chance have equal sand in your tires for balancing them? If so we have had the same problem. The sand gets caught in the stem and then it doesn't seal.
JAT
God bless,
John
That is why they make a specific valve stem made and intended for tires using Equal or other "media type" balancing material. Our tire guy always replaces ALL of our cores with these when doing our tires since he knows we run balancing material in at least the steer tires! (but he also knows we rotate back and keep fairly new tires on the "steers" too!)
FWIW ;D BK ;D
Quote from: Busted Knuckle on January 01, 2009, 09:33:06 AM
That is why they make a specific valve stem made and intended for tires using Equal or other "media type" balancing material. Our tire guy always replaces ALL of our cores with these when doing our tires since he knows we run balancing material in at least the steer tires! (but he also knows we rotate back and keep fairly new tires on the "steers" too!)
FWIW ;D BK ;D
Thanks BK. I think that we will get our stems changed. Any idea where to get them? A website or something. Or will our tire dealer know what they are?
Thanks for the info...You are such a wealth of info.
God bless,
John
BK,
Share with us what sort of "balancing material" you use and is that what you recommend? Are those rings full of oil and metal balls the best?
Thanks,
John
Let's try to keep on track here, I didn't say anything about stems - my problems are with valve cores.
I have regular two-piece truck tire stems and they work fine.
I have no internal balance stuff of any kind.
Quote from: buswarrior on December 31, 2008, 11:21:51 PM
Walmart is not a likely bus chassis parts supplier... Get familiar with your local heavy jobber. You'll be pleasantly surprised at what is available and at what cost and what quality.
Not to mention that if you have a good working relationship with these guys, they may let you know about good deals that they run across, or when a customer does an upgrade and leaves them with good parts.
. . .they also might get you in ahead of a commercial customer for a quick repair so that you can get on the road tonight instead of Monday.
WM is like any other discount retailer, some stuff is good and some is not so good.
I've been buying valve cores from different sources for many years and these are the first ones I ever had fail from any source except under unusual circumstances.
You cannot make a general statement that all stuff from any source is always good or bad, that just doesn't work.
I live in a very small town and my sources are limited.
Quote from: gus on January 01, 2009, 02:46:46 PM
Let's try to keep on track here,Has that EVER happened ;D I didn't say anything about stems - my problems are with valve cores.
I have regular two-piece truck tire stems and they work fine.
I have no internal balance stuff of any kind.
I am sorry. I did think you were talking about the stems...just my lazy reading not your post lol. I have no clue if the cores are any different but it does sound like something is amiss. Do you have valve caps on the stems? Could be some debris or water getting in there and fouling things up. I am getting my truck serviced in the AM..I will check and see what they say.
letz,
Not very often! I do the same thing, read the posts too fast sometimes, especially the really long ones.
>>>>>>>>>>>
I did some research today at two auto supply stores and two truck tire shops. The auto stores had the same cores as WM and, yes, they are made in China.
The truck shops told me that the long type of core is to keep balancing media out of the seal, but otherwise no different than the short type. I also removed the cores from two of my new spare two-piece truck valves and they are both short!!
Both truck tire shops told me there is no difference in pressure ratings for cores, that they all work in truck or auto tires. I had always thought this true but had read on some forums that some were different. On the other hand, maybe I'm thinking of valve caps or valve stems instead of cores?
I removed the two WM cores and installed two long type I got from a truck shop and hope for no more leaks. One of the two front valves with WM cores was already leaking!!
One last observation, I noticed that the WM core seals are about 1/3 wider than the ones from two or three other sources. What this has to do with anything I can't say!
I now know more about valve cores than i ever thought I needed to know!!
Thanks to all for your responses.