How a Manual Impact Driver Can Make Your Day – UnderhoodService

How a Manual Impact Driver Can Make Your Day

Sponsored by Summit Racing Equipment

We’ve all had screws and other fasteners that just refuse to budge. Years of corrosion, heat cycling, and gunk buildup due to weather exposure and normal vehicle operation can literally freeze a screw in place. And we can guarantee the screw head will strip if you use too much force trying to remove it.

But there is a tool that can help you remove those stubborn screws without tears. It’s the manual impact driver, and you probably have one in the back of your tool box. They aren’t expensive, and no other tool can really replicate what it does. Removing just one pesky fastener will convince you of its value.

If it’s been a while since you’ve used an impact driver or have never used one, its operation is simplicity itself. Just stick the appropriate bit in the driver, seat it on the fastener, and give it a few solid whacks with a mallet or hammer. The tool uses that force—up to 200 ft.-lbs. of torque depending on the driver—to turn the bit slightly, like 1/10th of a turn per whack. The impact will also be transmitted through the tool into the fastener just like an ordinary impact gun to shock the fastener loose in the process.

Here’s a testimonial to the value of a manual impact driver. A Summit Racing employee has a 2000 Honda Nighthawk 750 that was stored outside, close to the ocean. During a rehab of the bike, he noticed a few black spots under the kickstand, directly above the drive sprocket—a sure sign of a weeping oil seal.

Removing the sprocket cover revealed the drip was coming from the neutral switch, necessitating a seal replacement. It also revealed that a combination of salt air, chain grease, and road grit had made its way under the cover, corroding the two screws holding the switch in place. Using the correct Japanese Industrial Standard (JIS) bit (more on that below) and probably more force than he should have, our hero managed to remove one screw, but the other one wasn’t having it. He broke out the manual impact driver; a few raps with a hammer and that stubborn screw was sufficiently loosened so a regular screwdriver could remove the screw.

A few words of caution when using a manual impact driver. We totally understand the frustration that comes from dealing with a stubborn fastener, but be careful with that hammer.
On our friend’s Honda, he was dealing with an aluminum transmission case, plus a sprocket and the splined transmission input shaft sitting very close to the neutral switch. One errant hammer blow could have made a bad situation worse.

As good as an impact driver is, there is still a chance you could damage a fastener head during the removal process. It’s good practice to have some replacement fasteners handy; replacing a few is way easier than drilling out a seized one.

Tech Tip: Phillips Head vs. JIS
Have you ever come across a machine screw that has what looks like a typical Phillips head, but your Phillips screwdriver or bit doesn’t quite fit? Congratulations, you’ve met a Japanese Industry Standard (JIS) machine screw. JIS screws are found on most every Japanese vehicle made, so chances are good you’ve mangled a few with a regular Phillips screwdriver. The primary difference is in the cross slot on the screw head. A Phillips bit will not completely bottom out in a JIS screw head, which causes the bit to slip, or ‘cam out’. You know what happens next—you apply more force to get the bit to seat and end up stripping the screw head.

Here’s the kicker—JIS bits work just fine for Phillips head screws.

The moral of the story? Add some JIS screwdrivers or driver bits to your tool box and put the screw-stripping days behind you.

This article is sponsored by Summit Racing Equipment.

You May Also Like

6 Signs It’s Time to Put Down the Pen and Ditch the Paper

There’s no time to hesitate.  The surge in the aftermarket sweet spot — or vehicles in the six- to 12-year age range that will soon require significant repairs — reached 94 million in the first half of 2021, according to Experian Automotive. That total accounts for nearly 31% of all vehicles in operation.  That percentage

There’s no time to hesitate. 

The surge in the aftermarket sweet spot — or vehicles in the six- to 12-year age range that will soon require significant repairs — reached 94 million in the first half of 2021, according to Experian Automotive. That total accounts for nearly 31% of all vehicles in operation. 

Updating Your Shop’s Approach to Vehicle Filtration 

Customers may wonder what the biggest threats are to their engines.  Heat is one for sure. But the other are tiny – often microscopic – particles. If these aren’t filtered thoroughly, they will accumulate inside the engine, which will increase friction, heat and lead to significant damage to internal engine components. In time, it will

Oxygen Sensors – Technology, Types, Evolution, and Life Expectancy

Since the implementation of OBDII, the oxygen sensor has been a main staple of engine management systems. Modern oxygen sensors are much faster and more accurate than their older counterparts. This allows the engine to enter closed loop control faster which decreases emissions and fuel usage by as much as 15-20%.  O2 sensors are separated

Warn Your Customers About Water Pump Failure During the Summer

Summer is an opportune time for automotive professionals to remind customers to keep an eye on the signs of a failing water pump.  As you know, extreme summer temperatures and added strain on vehicles from activities like long road trips can cause engines to become more susceptible to troubles from excessive heat, making the function

Keep Drivers Comfortable with Airborne Contaminant Control

Oil changes are one of the first projects that DIYers and experienced automotive pros learn how to perform. This maintenance task is vital to vehicle performance, relatively easy to do and performed at regular intervals, so most customers understand its importance.  All drivers need to stay on top of oil changes, especially with more cars

Other Posts

Protect Your Fuel Tank and Pump With Delphi Technologies 

The fuel tank and pump are considered the lifeblood of a vehicle, supplying and circulating fuel to other critical components throughout the vehicle.  Delphi Technologies has been a manufacturer of fuel delivery parts for over 80 years, and a lot has changed since then.  With over 30 OE-proprietary innovations and 150 patents in fuel technologies

Trusted for R&D and factory fill for decades

ENEOS is the largest oil company in Japan, as the “original JDM oil” they’ve been working in partnership with Asian automakers for decades. As part of this partnership, ENEOS has in-house testing facilities where they follow strategies developed with each OEM partner to meet their vehicle and performance specifications, particularly for the tighter tolerances of

FRAM® Provides Next-Level Engine Protection for the Summer

For many people, road trips are an enjoyable summertime tradition. Whether you’re taking the family out on vacation, traveling for sporting events, or just hitting the road for some mind-clearing relaxation, summer usually means miles.  Since 1934, Pros and DIYers everywhere have relied on FRAM® to get the most complete engine protection. When it comes

Quality-Built Brake Pads and Rotors Powered by MPA

Backed by over fifty years of product innovation and engineering expertise, Motorcar Parts of America is proud to announce the addition of Quality-Built replacement brake pads and rotors to our extensive product portfolio. This full line of brake system components provides a wide range of application coverage and options for every type of driver and