What You’re Installing: The BL-ST-036
EMGRAND (Geely’s EMGRAND line) runs 433MHz TPMS on the vehicles covered by this sensor. The BL-ST-036 is a BH-Sens (Baolong Technology) clamp-in, pre-programmed unit with OE number 01725271. It weighs about an ounce and covers five dedicated OE vehicle applications, so confirm your exact model year and trim before ordering.
| Spec | Detail |
|---|---|
| Brand / maker | BH-Sens (Baolong Technology) |
| Frequency | 433 MHz |
| OE number | 01725271 |
| Type | Clamp-in, pre-programmed |
| Weight | ~1 oz (28 g) |
| Compatibility | Geely / EMGRAND applications |
Where a Clamp-In Sensor Actually Seals
Beginners assume the metal stem seals the hole. It doesn’t. The seal is the rubber grommet sitting between the stem base and the rim, squeezed by the nut on the outside of the wheel. That single fact explains almost every leak you’ll chase after a TPMS job. There are three fasteners to respect:
| Fastener | What it does | Practical guidance |
|---|---|---|
| Stem nut (outside rim) | Compresses the grommet against the rim | Single-digit N·m — usually well under 6 N·m. Use a torque wrench that reads in in-lb, not a 1/2″ drive gun. Specs differ by sensor and wheel; check the sensor spec sheet or the vehicle service manual. |
| Valve core | Holds air | Snug only. TPMS cores are nickel-plated; cranking them down deforms the seat and creates a slow leak. |
| Sensor-to-stem screw | Fixes the sensor body to the stem | Light torque. Overtightening cracks the housing, and a cracked housing means water ingress and a dead sensor in a few months. |
If you take one thing from this article: in-lb torque wrench, not feel.
Installation Sequence
- Deflate completely before breaking the bead. A pressurized tire fighting a bead breaker is how stems get bent.
- Position the valve away from the bead breaker. Rotate the wheel so the sensor sits in a safe clock position, then break the bead on the opposite side.
- Keep tire irons away from the sensor. It sits in the drop center during demounting — one careless lever stroke crushes the housing.
- Remove the stem nut and let the sensor drop into the tire, then retrieve it after the tire is off. Don’t let it fall onto concrete.
- Inspect, then decide. Bent stem, cracked body, corroded nut, torn or flattened grommet — replace it. Do not reuse a seal that has already been compressed once.
- Install the new service kit. Grommet on the stem, stem through the rim hole, washer and nut outside, hand-tight first.
- Lubricate the grommet with approved tire mounting lube — not oil, not grease, not WD-40. Petroleum products degrade the rubber.
- Torque the stem nut to spec with the wheel supported, not resting on the ground.
- Seat the bead, inflate to the door placard pressure, then leak-test the stem with soapy water.
- Relearn and verify with a TPMS tool.
Valve Stem Service: Replace It Every Time
A clamp-in service kit is cheap — grommet, washer, nut, nickel-plated valve core, cap. Reusing those parts to save a couple of dollars is the most expensive shortcut in TPMS work. The grommet takes a compression set the first time it’s torqued, so it will not seal reliably a second time. The valve core wears at the seat. The nut corrodes into the threads and either seizes or strips on the next service.
Rule of thumb: every tire removal on a clamp-in sensor gets a new service kit. Every time.
Four Mistakes That Cost Sensors
1. Impact wrenches on the stem nut. This is the number one killer. The nut needs a fraction of what a gun delivers, and there is no warning — the grommet just deforms, the housing cracks, or the stem threads shear.
2. Reusing the grommet or valve core. Covered above. It leaks slowly, the light comes on a week later, and the customer blames the sensor.
3. Mixing frequencies. 433MHz and 315MHz parts are not interchangeable, and neither are sensor protocols across model years. A “universal” sensor that wasn’t programmed to the right protocol will trigger the tool but never report.
4. Skipping the relearn. A pre-programmed sensor still has to be introduced to the vehicle. Some EMGRAND vehicles relearn automatically after several minutes of driving above a set speed; others need the ID written through a scan tool or triggered with an activation tool. Check the procedure for your specific model year — don’t assume.
After the Install
Drive the car, confirm all four positions report, and check pressure accuracy against a known-good gauge. If one corner reads wrong or drops, suspect the relearn or the grommet seal before you suspect the sensor electronics.
Recommended Part
For EMGRAND and other Geely applications running 433MHz clamp-in sensors, the BH-Sens BL-ST-036 (OE 01725271) is the direct-fit choice: pre-programmed, clamp-in, and light enough that it won’t throw off wheel balance. Order it here: BL-ST-036 | BH-Sens 433MHz TPMS Tire Pressure Sensor | Fits Geely | OE# 01725271
FAQ
How tight should the TPMS stem nut be?
Light. Clamp-in stem nuts generally fall in the single-digit N·m range, and many are under 6 N·m — well below what most people can judge by hand. Use a torque wrench rated in in-lb and follow the sensor manufacturer’s or vehicle service manual’s figure for your wheel.
Do I need a new service kit every time I change tires?
Yes, if you’re running clamp-in sensors. The grommet, washer, nut and valve core are wear items that take a compression set or corrode. New kits are inexpensive and prevent slow leaks that look like sensor failures.
Will a pre-programmed sensor work without a scan tool?
It depends on the vehicle. Some EMGRAND models relearn automatically during a drive cycle; others require the sensor ID to be written with a TPMS scan tool. Always verify all four positions report before returning the car.
Can I reuse my old valve stem with a new sensor?
No. Clamp-in stems are matched to the sensor body, and the old grommet won’t seal again. Install the sensor with its new hardware as a complete assembly.