Impact driver usage

[vdavidoff]

While splitting my GT550 case, I used an impact driver (as the shop manual directs) to remove the screws holding the oil guide on the right side of the motor. When reinstalling those screws, should I use an impact driver to seat them, or just screw them in by hand? I have never considered using an impact driver for putting screws back in, but now I'm thinking, maybe that makes sense.

Thanks.
Andy

[GT500Andy]

Andy I use one for the screws on the outer plates from the transmission and gear shift but never on the casings

Andy

[vdavidoff]

Wow, you really do hate impact drivers. I find my impact driver to be one of the most important tools I have when it comes to removing certain screws without destroying anything in the process. But, I'm not a professional mechanic. *shrug*

Hand tightening with thread lock seems a bit safer to me than tightening with an impact driver. Though I'd still love to know what more people think.

Thanks for your replies!

Andy

[ConnerVT]

Tightening screws with an impact driver is just foolish. Especially when the material is aluminum.

All fasteners have a relatively well defined torque specification, based on type of fastener, size, thread, and material. None of the specs I have ever seen states, "Unknown - as tight as you can make it".

If you speak with experienced machinists or mechanical engineers, they will tell you that fasteners are really designed for one use only. Threads distort, split washers dull, the underside of screw heads (used with split washers) develop burrs. All of these affect the holding power of a fastener.

Of course, holding the side cover on our bike is a bit less critical than, lets say, holding a wing flap on a F-16. But that doesn't mean there's reason not use sound engineering practices.

If the fasteners you are using are worn or distorted, replace them. Even better to replace them if the screw slots are chewed up -- save fighting them out the next time.

If the screw holes you are screwing something into are in poor condition, run a properly sized tap *gently* through them to clean them up. If really damaged, re-tap to the next size, or properly install a Helicoil.

Use a medium strength thread lock (Loctite) if there is a good reason to be concerned if a critical fastener will come loose.

And, since I've spent years working on very expensive manufacturing equipment, nothing beats using hex socket head screws, and tightening them down to torque specs with a torque driver.

[vdavidoff]

Thanks for all the information, Conner.

Andy

[Coyote]

What type of impact driver are we talking about? I can see no air or electric, but I couldn't live without my hand held impact driver. The type you hit with a hammer. Sure has saved a lot of those muck soft phillips screws that have taken a set. Saves rounding them out and then having to drill the head off.

[vdavidoff]

I'm talking about the type you hit with a hammer, which I thought was an "impact driver" vs. and "impact wrench", which is powered by air or electricity.

Andy

[Rustygt550]

Absolutely replace if you can but sometimes you can't and the way I remove tight or already butchered screws leaves even butchered reusable, and I will describe this if anyone is interested

Please explain I am interested

[Coyote]

PEDRO, I agree with not chasing threads with a tap. All threads are rolled on most Japanese motorcycles. That's how the washers get trapped on there. Anyway, it's a whole different production method. If you run a 6mm tap into a 6mm thread,, you will definitely remove material from the root of the thread as they are radiused zt the root. Not sharp like a standard tap, Be it a starter, plug or bottom tap.

[jabcb]

Some of us are undoubtedly amateur mechanics and would like to learn more about appropriate torques for our vintage bikes.

Service bulletin Specification-3 lists general guidelines for standard & extra strength "S" bolts. Doesn't list values for cadmium plated bolts but a note indicates the values are 30% lower than standard bolts.
http://www.ozebook.com/compendium/techb ... %201-5.pdf

And if you happen to need something to argue about, how about JIS screwdrivers?

[Suzukidave]

I also have always had a impact driver in my tool box , i cannot even start to count the times i have used mine to get out the made of butter philips head screws the japs put into everything .

[jabcb]

Got an impact driver back in the 70s. Only recently became aware that it has JIS philips bits which are different than the philips screwdrivers that I have. Just got JIS philips screwdrivers & they also fit the vintage Suzuki screws better.

Turns out that part of the reason this amateur mechanic used an impact driver was those JIS philips bits, which work better with the "made of butter" screws.

[vdavidoff]

Just want to make sure I'm following. You're basically saying, smash the raised cross section of the screw back into the screw, then reform the depressed cross section by driving the t-bar driver into what you just mashed down?

Andy

[Fritz500]

I bought my impact screw driver about 40 years ago and have used it about half a dozen times...when all else had failed (finesse and brute strength) and it popped out those stubborn screws each time.

As Pedro says you need a positive swing with a decent sized hammer as it should only take one good hit.

I never ever would consider it for tightening screws.

[CumbriaSuzuki]

PEDRO, I agree with not chasing threads with a tap. All threads are rolled on most Japanese motorcycles. That's how the washers get trapped on there. Anyway, it's a whole different production method. If you run a 6mm tap into a 6mm thread,, you will definitely remove material from the root of the thread as they are radiused zt the root. Not sharp like a standard tap, Be it a starter, plug or bottom tap.

How do you roll internal threads? I can understand it for bolts and screws but I've never done them internally before.