TST 507 sensor question

[Ron3rd]

I've got the TST 507 system, about 5 years old and it works fine. I want to replace the little valve stem seals in the sensor (where it seals against the valve stem) and my question is; how do you get the old seals out??!! I'm using a small pick and it's being difficult. For those of you that have replaced these seals, any tips are appreciated.

[Ron3rd]

Dutch_12078 wrote:
I've picked damaged stem seals out of my TST 507 sensors using a dental pick. When I needed some extra cap seals, TST kindly sent them to me at no charge, but I haven't needed more stem seals yet.

Curved dental pick (bought a set from Harbor Freight years ago) is exactly what I used. Couldn't see any other way to get them out!

[Ron3rd]

John Wayne wrote:
When you get the new seals in .Take an old valve stem put a SMALL amount of anti seize on the stem and screw on the sender putting a small amount of anti-seize on the seal. This will prevent the seal from tearing when being screwed on. Repeat every year if you take them off between trips.

Very good idea, thanks for the tip.

[Ron3rd]

loggenrock wrote:
Those extra O-rings are replacement for the battery caps - you just need to really stretch them out. I never saw spare O-rings to go INSIDE the part that goes on the valve stem... ST

Yes, I know what you're talking about, the little o-rings that you stretch way out to seal the screw-on battery cap; I've got those covered.

The one I'm talking about is the seal that you will see if you take the sensor off and look into the valve stem hole. It's not easy to see, they flatten out, but the they do eventually crack and need to be replaced or you will have a leak. If you look at the replacement parts you should have gotten with your 507, the valve stem seals look more like a thick black plastic washer with a square shoulder, maybe 1/4" in outside diameter. I was expecting an o-ring but that's not what they use to seal this area.

[Ron3rd]

Lynnmor wrote:
The seals for the valve stem are wrapped around a plastic center piece that is easy to break, ask me how I know.

Good to know, luckily I did not break them taking the seals out.

[Ron3rd]

fj12ryder wrote:
Sorry, I thought when you said it was working fine, that everything was okay. I got a bunch of extra O-rings with my TST TPMS, but haven't needed them yet. Only thing I've had to do is replace the batteries, but they've lasted a long time. I do remove them over the winter when it's in storage.

Yeah, I got the replacement o-rings too, but the little valve stem seal was the one that had me scratching my head. The little square-shoulder seal they gave me did not look correct but I found it was after getting the old ones out. Looks like it would be to big and should be a round-shoulder o-ring, but that is not the case. I left a message at TST and a lady called me back and confirmed I had the correct seals. They're not that easy to take out and replace and the instructions do not address the issue but I got it figured out! All is working well now.

[Lynnmor]

The seals for the valve stem are wrapped around a plastic center piece that is easy to break, ask me how I know.

[Dutch_12078]

I've picked damaged stem seals out of my TST 507 sensors using a dental pick. When I needed some extra cap seals, TST kindly sent them to me at no charge, but I haven't needed more stem seals yet.

[loggenrock]

Those extra O-rings are replacement for the battery caps - you just need to really stretch them out. I never saw spare O-rings to go INSIDE the part that goes on the valve stem... ST

[Ivylog]

Double post:S

[Ivylog]

I use the cork screw on my Swiss Army knife.

[fj12ryder]

Sorry, I thought when you said it was working fine, that everything was okay. I got a bunch of extra O-rings with my TST TPMS, but haven't needed them yet. Only thing I've had to do is replace the batteries, but they've lasted a long time. I do remove them over the winter when it's in storage.

[Ron3rd]

fj12ryder wrote:

Ron3rd wrote:
I've got the TST 507 system, about 5 years old and it works fine. I want to replace the little valve stem seals in the sensor (where it seals against the valve stem) and my question is; how do you get the old seals out??!! I'm using a small pick and it's being difficult. For those of you that have replaced these seals, any tips are appreciated.

Why do you want to mess with it if it's working fine? Never forget the old adage: "If it ain't broke, don't fix it".

Get where you're coming from, but it is "broke". Seals have broken down and leaking, causing alarms after 5 years. I've never replaced them. It's time now and I figured it out; you need a small curved dental pick to get the old ones out. New ones are forced in, they sit in a counterbore; it's not intuitive but I got it going.

TST gave me extra seals when I bought the unit but they did not look right for the application. Got the old ones out and they're the same as the replacements, so I got it figured out and all is well. TST btw has no heads-up on this online, but overall it's a very good system and I otherwise have no complaints.

[Ron3rd]

John Wayne wrote:
When you get the new seals in .Take an old valve stem put a SMALL amount of anti seize on the stem and screw on the sender putting a small amount of anti-seize on the seal. This will prevent the seal from tearing when being screwed on. Repeat every year if you take them off between trips.

Good tip, thanks.

[fj12ryder]

Ron3rd wrote:
I've got the TST 507 system, about 5 years old and it works fine. I want to replace the little valve stem seals in the sensor (where it seals against the valve stem) and my question is; how do you get the old seals out??!! I'm using a small pick and it's being difficult. For those of you that have replaced these seals, any tips are appreciated.

Why do you want to mess with it if it's working fine? Never forget the old adage: "If it ain't broke, don't fix it".