Tool Review: Liquid Wrench Pro Penetrant

Feb. 13, 2018
The reviewer appreciated that this penetrant had an LED light above the spray nozzle.

Liquid Wrench offers Pro Penetrant and Lubricant powered by FlashSight Technology. The product features a built-in LED light located directly above the spray nozzle, enabling users to see where they spray to improve accuracy in low-light areas. The new product formulation delivers the power of a penetrating oil able to cut through rust, grease and corrosion with a long-lasting lubricant that reduces friction and wear, the company says.

The review

When it comes to spray penetrant, accuracy of the nozzle is the difference between just blindly blanketing the area and concentrating it where a technician needs it. For Eric Moore of DeMary Truck in Ohio, the Liquid Wrench Pro Penetrant applies exactly where pointed. The built-in LED light above the spray nozzle was a stand-out feature for Moore, because it allowed him to aim the product without much waste.

"The LED really surprised us [technicians at DeMary Truck] with the accuracy, and made us wonder how we used penetrants in the past without one," Moore says.

Moore says the LED feature saves time on the job because technicians aren't forced to try to hold a light on the area while applying the product, and it eliminates the need to reapply after blindly spraying.

"I think lots of penetrant is wasted when it can’t be applied precisely," Moore says.

DeMary Truck technicians used the Pro Penetrant in a variety of applications, and found that it's a "great product for getting things loosened up."

While loosening U-bolts on the rear axle of a Mitsubishi FE, Moore put Liquid Wrench Pro Penetrant with LED head-to-head with other penetrants he uses in the shop as a comparison, like WD-40 and Kroil.

Moore says the Pro Penetrant was slightly better than WD-40 at penetrating into the threads of the nut, but needed more than one application. Kroil, for reference, worked with only one application.

"The lubricity and penetrating action of Liquid Wrench Pro Penetrant with LED is just above what we would consider average," Moore says.  "It performed well, and didn’t seem to break down."

Moore says while the technicians at DeMary Truck have used "numerous penetrants" throughout the span of their professional careers, the LED is a great addition that may elevate this product above others in the category.

 The product offers three spray positions, "Off," "Spray" and "Spray with Light." It is ready to go once the top is twisted into position.

While the penetrant does include a straw for more precise application, Moore says he would like to see Liquid Wrench come out with another attachable extended flexible spray tube to get in more hard-to-reach places.        

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