NSF-certified UV fluorescent dyes that pinpoint leaks in hydraulic oil, engine oil, and cooling water using a UV lamp. Choose from a full lineup of 4 oil-based and 2 water-based dyes — 6 SKUs matched to the carrier fluid and application.
UV fluorescent dye is a leak detection additive that is mixed into a carrier fluid (hydraulic oil, cooling water, etc.) and then illuminated with an ultraviolet (UV) lamp so that any leak points fluoresce brightly and can be located precisely. It is an established method adopted by hydraulic OEMs, automakers, and HVAC specialists. Inject the dye at 0.05% of the carrier fluid volume and operate the equipment for half a day to a full day; any fluid escaping from a leak will glow under UV light, revealing pinholes and seepage-level leaks that are invisible to the naked eye. The dyes are NSF certified, so they are safe for use in food-processing environments.
Leak detection dyes for oil-based carrier fluids — hydraulic oil, engine oil, refrigeration lubricant, and more. Select by emission color and volume.
Oil Finder Yellow
Volume: 1000ml
Oil Finder Yellow (case pack)
Volume: 1000ml × 12 bottles
Oil Finder Yellow
Volume: 30ml × 5 bottles
Dark Blue Emission
Volume: 946ml
White Emission
Volume: 473ml
Red Emission
Volume: 473ml
Leak detection dyes for water-based carrier fluids — coolant, water glycol, and process water. Select by emission color.
Blue Emission
Volume: 473ml
Green Emission
Volume: 473ml
UV-A lamps with a 365nm center wavelength that excite the fluorescent dye and make leak points glow. Choose from UV intensity 4,700–30,000 μW/cm² models to match your power source (rechargeable, battery, dedicated battery, or AC). See the UV light lineup for fluorescent dye for full specs.
Leak Tracker Plus (high-intensity rechargeable)
UV intensity 30,000 μW/cm² / 9 hr runtime
High-intensity UV lamp (11.2V dedicated battery)
UV intensity 30,000 μW/cm² / 22cm beam
Leak Tracker Mini (compact, battery)
UV intensity 30,000 μW/cm² / 3× AAA battery
Uvision365 A/C ultraviolet lamp
UV intensity 4,700 μW/cm² / AC100-120V/DC12V
Bundles combining UV fluorescent dye with a UV light. A convenient option when introducing UV fluorescent leak detection for the first time.
Includes: LL-OFY-Q (1000ml) + SPI-LTPR
Includes: LL-OFY-P5 (30ml × 5) + SPI-LTM
A spray cleaner that quickly washes away fluorescent dye left on surfaces after inspection.
Simply spray it onto the stained area and wipe away immediately — reducing cleanup time.
UV Dye Cleaner
Volume: 60ml
UV fluorescent dye reveals oil and water leaks in hydraulic equipment and cooling systems through a simple process: add → operate → UV illumination → pinpoint the glow. Because the inspection is non-destructive and runs while equipment is operating, you minimize downtime and enable predictive maintenance.
Here is how to use the dye in practice, using the oil leak detection dye “Oil Finder Yellow (LL-OFY-Q)” as an example. Because you can inspect while the equipment keeps running, you pinpoint micro oil leaks while keeping downtime to a minimum.
Add the dye to the oil tank of the leaking equipment at 0.05% by volume. For used oil or certain oil types, increase the dosage to around 0.2%. The small dose fluoresces brightly without affecting fluid performance.
After adding, run the equipment for about half a day to a full day so the dye spreads through the system. Then shine a UV light on any suspected leak point to make the leak fluoresce. Darkening the surroundings makes the seeping dye stand out even more clearly. → See UV lights for fluorescent dye
Detect micro oil leaks in hydraulic systems of machine tools and industrial machinery with high precision. Seepage-level leaks invisible to the naked eye glow clearly under UV illumination, enabling early repair and reduced downtime.
Quality assurance for heavy machinery, construction equipment, pumps, and piping components. Circulating the fluorescent dye and scanning with a UV lamp before shipment catches micro-leaks so every unit ships at full quality.
Pinpoint leak detection in refrigerant piping. Adding dye to the refrigerant and circulating it through the system reveals the exact leak point — even in complex piping layouts.
Real-world examples of Oil Finder fluorescent dye in the field. Even on piping caked with grime and iron powder, or on seepage too faint to judge by eye, circulating the dye and shining a UV lamp pinpoints the leak.
An aging machine in service for over 30 years was losing a full drum of hydraulic oil every four days. Iron powder on the piping left the leak point unidentified, but with the dye circulated at 0.05% beforehand, a UV lamp pinpointed the leak even on heavily fouled components.
The source of a hydraulic oil leak on a snow-removal wheel loader was unknown, and oil leaks on snowy roads are a particular hazard. With the dye, the leak at the control valve elbow was found easily.
It was difficult to tell an actual leak from externally deposited fluid, and inconclusive visual checks meant an overhaul — driving up inspection man-hours. A genuine leak at the engine mating surface can now be told apart from residue, making the dye ideal for pre-shipment inspection.
OIL-GLO Ultra fluorescent dye is NSF-certified and meets food-grade processing requirements. With its ultra-high concentration formulation requiring only a small dose (0.05%), it does not affect the performance of the fluid.
It supports oil-based fluids such as hydraulic oil, engine oil, spindle oil, gasoline, diesel, and jet fuel, as well as water-based fluids such as coolant and water-glycol. Choose the oil-type or water-type fluorescent dye according to your application.
Yes. UV fluorescent dye inspection is non-destructive and requires no shutdown. Simply add the fluorescent dye, operate the equipment for half a day to a full day, and then illuminate with a UV lamp. Leak locations can be identified in real-time while the equipment is operating.
Please feel free to contact us for product details, quotes, and more.