Catch coolant loss early
Direct level monitoring warns you when coolant drops below the probe—not after engine temperature has already climbed.
Australian Made Since 1978 Quality Reliability Local Support
WL701 Low Coolant Alarm
Stop engine damage before it starts.
The Bolec WL701 detects sudden coolant loss early and alerts you before overheating becomes an expensive engine failure.
✓ 12V & 24V compatible ✓ 7-second slosh delay ✓ Built-in fail-safe
IN 7 SEC
0+Years Australian made
0 secAnti-slosh delay
12/24VDual-voltage compatible
30 daysMoney-back guarantee
Why protection matters
A small warning can prevent a very big repair.
A split hose or sudden coolant leak can overheat an engine before the factory temperature gauge reacts. WL701 watches the coolant level directly, giving you time to stop safely.
Reduce costly engine damage
Early action can help prevent warped heads, failed gaskets and the downtime that follows a major overheating event.
Drive with confidence
A clear buzzer and optional warning light give drivers an unmistakable signal when attention is needed.
Built for real-world conditions01 / EARLY WARNING 02 / SMART DELAY 03 / FAIL-SAFE 04 / FLEXIBLE
Smart enough for rough tracks. Simple enough to trust.
Purpose-built protection for 4WDs, diesel vehicles, agricultural machinery and equipment that cannot afford an unexpected stop.
Engine protection
Alerts you before coolant loss turns into overheating and costly damage.
7-second slosh filter
Reduces nuisance alarms caused by steep climbs, corners and rough terrain.
Broken-wire alert
Sounds the alarm if the probe connection is interrupted, so a wiring fault cannot go unnoticed.
Relay output
Connect an external lamp or integrate with compatible shutdown systems.
Choose your protection
Two kits. One clear warning.
Select the probe and fitting style that best suits your installation.
WL701 Basic Kit
For straightforward installations using a push-on probe.
$220 incl. GST
- ✓ WL701 alarm module
- ✓ 8-way plug and brass terminals
- ✓ WL601P push-on probe
- ✓ Built-in buzzer and relay output
WL701 4WD Kit
Complete kit for LandCruiser and other 4WD installations.
$240 incl. GST
- ✓ WL701 alarm module
- ✓ Pre-made wiring harness
- ✓ 1/8 NPT probe and brass weld-in boss
- ✓ External LED and instructions
✓ 30-day money-back guarantee. Try the WL701 with confidence. If it is not right for your application, you are protected by our satisfaction guarantee.
Beyond the radiatorReliable level monitoring wherever equipment needs protection.
Versatile applications
More than a vehicle alarm.
WL701 can also monitor conductive liquids in irrigation systems, equipment and storage tanks.
4WD & touringAgricultureIrrigationDiesel equipment
Cost-effective protection
Help reduce the risk of expensive equipment damage caused by sudden liquid loss.
Pump and tank monitoring
Use the relay output for compatible pump-control or alert applications.
Plastic tank compatible
Install a second probe to create the required earth path in non-conductive tanks.
“
The installation was straightforward, and the alarm is loud and clear. It is a simple, effective device that gives me real peace of mind.— WL701 customer
Common questions
Know before you install.
Still unsure about compatibility? Call our Melbourne team and we will help you choose the right setup.
It monitors coolant at the probe and triggers the built-in buzzer, an optional warning lamp or a relay output when the level drops. This gives you early warning before overheating causes major engine damage.
Yes. The WL701 is designed for 12V and 24V DC negative-ground systems.
The approximately seven-second slosh delay averages out momentary level changes caused by rough terrain, corners and steep climbs, helping reduce nuisance alarms.
Yes, if you are comfortable with basic automotive wiring. The 4WD kit includes a harness, probe, external LED and instructions. Keep sensor wiring away from motors, solenoids and ignition systems.
With the ignition on, remove the wire from the probe. After about seven seconds, the LED should illuminate and the alarm should sound. Follow the installation manual for the full test procedure.
Inspect the probe after the first six to eight weeks. Coolant additives can leave deposits, so use that initial result to set an appropriate ongoing inspection interval.
Local product support
Need help choosing?
Talk to Bolec about installation, vehicle compatibility, technical questions or trade pricing.
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