Symptoms
- Wrench slips around the pipe instead of turning it
- Jaw teeth look worn smooth or filled with debris
- Wrench bites momentarily then slides
- Excess force needed to get any bite at all
Likely causes
- CommonJaw teeth worn down from heavy useSerrated teeth gradually round off and lose their grip on pipe surfaces.
- CommonDebris, rust, or old pipe dope filling the teethBuildup between the teeth prevents them from contacting the pipe directly.
- PossibleWrench applied at the wrong angle or pushed instead of pulled correctlyPipe wrenches only bite properly when pressure is applied toward the opening of the jaw.
- Less commonWrench too small or large for the pipe diameterAn improperly sized wrench doesn't engage the jaws fully.
What to do
- Clean the jaw teeth with a wire brush to remove rust, pipe dope, or debris that's filling the serrations.
- Confirm the wrench size is appropriate for the pipe diameter; the jaws should open enough to grip firmly without maxing out.
- Position the wrench so pulling the handle tightens the jaw's bite onto the pipe, in the correct rotational direction.
- Use two pipe wrenches when possible, one to hold the fitting steady and one to turn, to prevent the pipe from just spinning.
- Check for worn or rounded teeth; if cleaning doesn't restore grip, the jaws may be worn out and the wrench should be replaced.
- Avoid using a pipe wrench on finished or chrome fittings, since the teeth will mar the surface; use a strap wrench instead for those.
- Store the wrench with the jaws protected from other tools to reduce future tooth wear.
Tools and parts
- Pipe wrench
- Wire brush
Replacement pipe wrenchSearch: “pipe wrench correct size”
When to call a pro
Not a professional job; a plumber can advise on the right wrench size and technique for stubborn or delicate fittings.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.