Can i use liquid wrench penetrating oil on a large pvc water shut off valve? it runs to a waterfall. it has been buried for years and won't budge.

It should not hurt the pvc. If valve has been buried, I would first clear around it then clean it as best as possible. Take a hair dryer or heat gun(be very careful with heat gun) and warm, just warm valve, let cool and warm again. Apply liquid wrench let sit 10-20 mins. Use valve wrench to try and open valve, repeat id necessary. Heat done right(low) ought not cause any problems with liquid wrench which is a flammable.

After it dries, does anyone knows if it will prevent rust?

It does prevent rust. Been using liquid wrench for 40 years to prevent rust on my tools stored in my garage. After iI use a metal tool I spray it with Liquid Wrench. Never lost a tool due to rust.

Is it safe to use for breaking loose rusted stuck exhaust bolts? i know it is flammable but i figure i could clean it off after i get the bolts out.

It won a comparison between 5 other well known rust penetrators by a well know product evaluator on YouTube. But the ultimate exhaust bolt fix is heat if all else fails.

Does this form a foam when sprayed on ??? J. Payne

No, it is more like the consistency of WD-40. It bubble a little when you first spray it (probably from the propellant) but it leaves more of a thin (penetrating) oil residue.

Material	Plastic
Brand	Liquid Wrench
Package Information	Can
Liquid Volume	1951.85 Milliliters
Item Weight	7 Pounds
Flash Point	56 Degrees Celsius
Item Form	Liquid
Global Trade Identification Number	00078698408606
Manufacturer	Liquid Wrench
Unit Count	66.0 Fluid Ounces
UPC	078698408606
Number of Items	12
Model	L106-12PK
Item Weight	7 pounds
Product Dimensions	8.8 x 6.8 x 7.4 inches
Item model number	L106-12PK
Manufacturer Part Number	L106-12PK

Penetrating Oil Spray – Lubricant for Bolts, Nuts & Locks – Helps Loosen Rusted Parts, Cuts Through Grease, Low Odor – Long-Lasting Lubrication – 5.5 oz (Case of 12)

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