Tire monitor system question

[DannyA]

Looking at getting the TST system and know they recommend metal valve stems but wondering how many have not changed to metal stems and any problems using the ones that came on there.
It came with nitrogen in the tires and I hate to change that out if I don't have to.

[Dutch_12078]

Airstreamer67 wrote:
That looks like it could work.

The problems I have with the ready-made variety are the length of the stem and the configuration of the bottom.

I could use the Drimmel to shape the bottom, I presume, but I don't know if the material they are made of would shape as well as my water-pipe specials. I don't have a flat surface on my wheels at the bottom of the stems, so I need to reshape to make the stem fit securely.

So, I didn't reinvent the wheel, just the wheel stem covers.

Boy Scouts Can Survive.

The covers are made to fit standard length valve stems. As long as the cover contacts the rim on the circumference of the wheel, the stem would be stabilized against the centrifugal forces that could potentially distort the rubber stem due to the extra 1/2 ounce or so of the sensor.

[Airstreamer67]

That looks like it could work.

The problems I have with the ready-made variety are the length of the stem and the configuration of the bottom.

I could use the Drimmel to shape the bottom, I presume, but I don't know if the material they are made of would shape as well as my water-pipe specials. I don't have a flat surface on my wheels at the bottom of the stems, so I need to reshape to make the stem fit securely.

So, I didn't reinvent the wheel, just the wheel stem covers.

Boy Scouts Can Survive.

[Dutch_12078]

With metal valve stem covers readily available at a nominal cost, I don't think I would expend too much effort "reinventing the wheel".



TPMS Tire Valve Stem Cap & Sleeve cover chrome set

[Airstreamer67]

BurbMan wrote:

Airstreamer67 wrote:
I got a piece of thin plastic pipe that fits over the rubber valve stem, cut it to size to allow the sending unit to screw fully on the valve stem, modified the bottom of the plastic pipe with a Drimel to fit the curve of my wheel, and placed it over the rubber valve stem. It keeps the PressurePro sender from flexing the stem, thus making it "act" like a steel valve stem.

You should sell that idea to PressurePro, they can package them with their product.

The reason I made the valve stem cover was my tire dealer didn't have the size of steel valve my travel trailer needed. Most steel valves go on truck tires, and my rims are a different size and configuration. He said he could try ordering them, but I was going on the road and didn't have time to wait.

So, I went to Ace and bought a 10-foot length of half-inch plastic pipe, a Schedule Something-or-Other which had thin walls and was lighter.

I used a pipe cutter to cut the needed length to fit my particular rubber valve stem and used the Drimmel to carve the shape needed for the bottom of the pipe to fit my particular wheel. The length was cut so that the PressurePro sending unit can screw fully on.

It took maybe 10-20 minutes to cut and shape the first one, and each subsequent one much quicker since the cut dimensions and shape are identical for each wheel.

With the pipe in place, the stem is held taut by the screwed-down sending unit and cannot flex.

Now I got about 9.5 feet of pipe left, which I figure should be good for another 115 tires.

[DannyA]

Just a note: Ordered the TST system Wednesday and got a notification this morning that it will be here Friday, that is fast!!!

[westend]

K.Reeve wrote:
ok, not a tire guy, so I want to know, do they mount the tire then apply a vacuum to purge all the air out of the tire without sucking the sidewalls off the rim, and then fill with nitrogen? or do they just mount the tire like any normal shop, then just fill with Nitrogen? if so why are we paying a premium price for this service? air is already 78-79% Nitrogen already, so really your Nitro filled tires are what %? at what cost? ill stick to old fashioned air thanks.

Ah, so there's at least one more guy thinking about it on this Forum.
Atmosphere is 14 psi when the tire is filled. the tire is then pressurized to 45 psi. One third of the pressure contains 80% nitrogen and 2/3 contain 100% Nitrogen = 93% nitrogen. It's not exactly like that because more volume of N is introduced to make up the difference in pressure but there is still some dilution.

I will believe nitrogen is better when someone can explain to me the value of putting a green cap onto the stem. 😉

I'm liking that stem cover idea, though. I thought I told the tire shop to use metal stems but that didn't happen. I bet I could buff up some aluminum tube to look pretty good.

[K_Reeve]

ok, not a tire guy, so I want to know, do they mount the tire then apply a vacuum to purge all the air out of the tire without sucking the sidewalls off the rim, and then fill with nitrogen? or do they just mount the tire like any normal shop, then just fill with Nitrogen? if so why are we paying a premium price for this service? air is already 78-79% Nitrogen already, so really your Nitro filled tires are what %? at what cost? ill stick to old fashioned air thanks.

[BurbMan]

Airstreamer67 wrote:
I got a piece of thin plastic pipe that fits over the rubber valve stem, cut it to size to allow the sending unit to screw fully on the valve stem, modified the bottom of the plastic pipe with a Drimel to fit the curve of my wheel, and placed it over the rubber valve stem. It keeps the PressurePro sender from flexing the stem, thus making it "act" like a steel valve stem.

You should sell that idea to PressurePro, they can package them with their product.

[BurbMan]

powderman426 wrote:
I would put on the metal valve stems and use the 80% nitrogen mix.

Wow sounds expensive where do you get the 80% mix?

[GMandJM]

Airstreamer67 wrote:
I got a piece of thin plastic pipe that fits over the rubber valve stem, cut it to size to allow the sending unit to screw fully on the valve stem, modified the bottom of the plastic pipe with a Drimel to fit the curve of my wheel, and placed it over the rubber valve stem. It keeps the PressurePro sender from flexing the stem, thus making it "act" like a steel valve stem.

Excellent idea. I hope you patent that idea and make a gazillion bucks selling those.

Would love to see a picture if you can post one.

[pasusan]

Airstreamer67 wrote:
I got a piece of thin plastic pipe that fits over the rubber valve stem, cut it to size to allow the sending unit to screw fully on the valve stem, modified the bottom of the plastic pipe with a Drimel to fit the curve of my wheel, and placed it over the rubber valve stem. It keeps the PressurePro sender from flexing the stem, thus making it "act" like a steel valve stem.

This is a great idea.

We got some chrome valve stem covers that keep them from flexing - and they look pretty too.

[Us_out_West]

Our 507's (non-flow thru) arrived last week and will install on our rig wheels before a trip to the Mid-West from Reno in early May.

Side note; friends of ours installed their 507 flow thru's on their wheels couple weeks ago and on startup they showed one tire with low pressure and leaking. Checked pressure manually and it confirmed. Swapped sensors after putting more air in and readings were fine. Turned out the original sensor was pinching the stem and causing the leak. Sensor was fine...operator error.

Nice before heading out to know what your tire pressures are...besides the monitoring on the road.

[Bull_Rider]

We have the TST-507 system. I had rubber valve stems on the truck wheels. We had a failure just west of Palm Springs due to the valve stem rubbing against the wheel. On our wheels the valve stem sits down in a recess.

In a bit of an irony, the system did alert that we had a slow leak, the leak was caused by the sensors flexing the valve stem.

Changed out to metal stems at the next stop over.

Love the system, wouldn't RV without one.

[Water-Bug]

powderman426 wrote:
I guess it depends on your comfort level. I would put on the metal valve stems and use the 80% nitrogen mix.

For those that didn't catch it, air is 78.09% nitrogen. So, use metal valve stems and air. A difference of 1.91% nitrogen is irelivant.

EDIT. The difference in 78% and 100% nitrogen is questionable. The major difference is that 100% nitrogen is dry and air can contain variable amounts of humidity (water), which is another debatable topic. Race cars use 100% nitrogen because it eliminates a variable. Repeat performance is very important when a 500 mile race can be determined by a tenth of a second.