Supercool Car Radiator Coolant Cooling System Leak Detector Dye 29.5ml

Works really well, even without a black light you can clearly see the leaks, recommend.

Good quality dye, not much more to say. Got it to find a leak in my cooling system and found 4! So yeah, works as advertised.

Very good product. Helpful I find leak in 5 min

It serves its purpose.

Expensive for the quantity, but it did the job. Found my leak immediately. Bought a UV lamp to assist detection but didn't need it as the dye is so bright.

Excellent, but beware it shows leaks you didn’t know you had.

DON'T BE CONFUSED... this is UV reactive, just not out the bottle. That was my mistake. It becomes fluorescent when mixed with coolant and turns yellow. I was struggling to find a stubborn leak and this found it. For any rookies out there, little guide once poured in - put the coolant cap back on and drive it for around 30 mins if safe depending on how much you lose coolant. Car needs to get up to temperature for the thermostat to open so coolant flows through the system. Once this is done, you can also check heater core issues - passenger footwell area. Once up to temperature put your heaters on, that can help reveal heater core leaks. One tip: if using a UV torch, dont assume every glowing bit is a leak. Some things can show up white/blue-ish under UV. This dye turns fluorescent yellow when mixed with coolant, so that’s what you’re looking for. Dont just check obvious places. People may not realise it’s not just the radiator and pipes near it. Check water pump, bulkhead area (behind engine where pipes go into the cabin), thermostat, all pipework, radiator and seals, expansion tank (prone to cracking), and in some cases even exhaust/tailpipe area if coolant is burning through the engine. Found my leak when nothing else did.

Did exactly what it was supposed to do. Works best when you check at night using a black light torch (only needs a small torch) Confirmed my thoughts and proved the garage wrong (saved me a lot of time and money).

Sooooo very concentrated and BRIGHT. This product helped me diagnose a gremlin in my coolant system. 5/5 stars, great product.

The only Radiator specific dye that i could find. All others are for oil and are not compatible with coolant. It works amazing and it glows really bright fluorescent yellow under 365nm uv light form a cheap torch. The ammpount was more than enough for a very large LR4 V8 with dual AC system.

This stuff worked great, one ounce was more than enough. For those who said the product didn’t fluoresce in the bottle, I believe it needs to mix with the coolant/water to really light up. Remember this is to be used with a black light/UV light to see the leak. While it was bright enough to see some areas with no artificial UV light, it is ideally used with a UV light. Super bright for me, showed the leak clearly and was in an area that I never would have thought of or found without the leak detector.

Very strong, only need a little bit to make all of the coolant extremely uv visible. Helped me find my leak

This dye works perfectly for finding radiator leaks. It’s easy to use and does exactly what it’s supposed to. Just be careful not to spill it, because it can slightly stain bright aluminum if it sits for a while. A UV light is technically needed, but you can actually see it with the naked eye—just not very bright. Overall, a very effective leak detection dye.