Setting taper via impact?

[JHZR2]

I had a little time tonight after putting the kids to bed, to start putting together the lower control arm. That really means the lower ball joint to connect the knuckle, and the upper ball joint for the upper control arm.

Because there’s no shock or spring, there isn’t a force on the LCA, and I also had a hard time getting the upper one to set. Hand tools just let the ball joints spin. I cautiously tried an impact, I didn’t want to spin the ball joint fast, but I did run it in short bursts, and it seemed to move the nut and allow the tapers to cinch.

What I don’t know is if this is an acceptable approach.

When I replaced the ball joints a month or so ago, the rest of the suspension was together. I could use a long pry bar to force the upper one to hold, and I dont recal the lower one having an issue.

Maybe this is a newbie type question, but if the ball joint doesn’t spin, and the tapers come together, is using an impact an appropriate way to do this?

I’ll do final torque by hand. I just don’t want to mess something up.

Thanks!

 

[D60]

I do it frequently. Never wondered if it's considered good or bad.

 

[spasm3]

I don't like to use impact on strut rod retaining bolts, but on some i've had to as there was no way other wise ( can remember what car).

What i did was apply a bit of antiseize back the nut way off so it can build up free speed from the impact gun, and let off as soon as the strut rod would spin.

Does it hurt anything in the strut or in your case the ball joint ? I have no idea.

 

[paulo57509]

I've done many that way when I couldn't load the suspension. Finish with hand tools.

At one time, GM listed a Kent-Moore tool to seat the tapers. They looked like a long nut (in the drawings). You position the component in the taper, screw down the J-tool and tighten to 20 N-m. Remove them and install the nut and tighten to 48 N-m. I don't think the tool torque is critical. Just the torque for the actual nut. You can pretty much emulate this with an impact. Just set he impact to minumum torque.

I've never seen these tools in person. I think the ID might have a clearance for the end of the tapers so the tool pulls the taper onto the tapered hole.

 

[Trav]

No problem just don't let it impact too long, you can crack aluminum knuckles doing that.

 

[JHZR2]

I've done many that way when I couldn't load the suspension. Finish with hand tools.

At one time, GM listed a Kent-Moore tool to seat the tapers. They looked like a long nut (in the drawings). You position the component in the taper, screw down the J-tool and tighten to 20 N-m. Remove them and install the nut and tighten to 48 N-m. I don't think the tool torque is critical. Just the torque for the actual nut. You can pretty much emulate this with an impact. Just set he impact to minumum torque.

I've never seen these tools in person. I think the ID might have a clearance for the end of the tapers so the tool pulls the taper onto the tapered hole.

View attachment 162166

Actually some reading I did indicated that getting a non locking nut can often help to Vince it down. Then once the tapers set, remove that nut and install the locking one.

 

[JHZR2]

No problem just don't let it impact too long, you can crack aluminum knuckles doing that.

Thanks. I didn’t impact it far, and used a lower torque setting on a Milwaukee stubby. I’ll redo it this way tomorrow and torque properly by hand tomorrow.

 

[mrbreezeet1]

Actually some reading I did indicated that getting a non locking nut can often help to Vince it down. Then once the tapers set, remove that nut and install the locking one.

That's a good idea!
I hate those locking nuts for ball joints and tie rod ends.
They should just use the old style castellated nuts and a cotter pin.

 

[D60]

That's a good idea!
I hate those locking nuts for ball joints and tie rod ends.
They should just use the old style castellated nuts and a cotter pin.

As do I. Plus sometimes it's cheap hardware that is quite difficult to install. On things that aren't tapered like sway bar links I'll often toss the supplied locking nut and use a regular nut with threadlocker.

 

[paulo57509]

I've done many that way when I couldn't load the suspension. Finish with hand tools.

At one time, GM listed a Kent-Moore tool to seat the tapers. They looked like a long nut (in the drawings). You position the component in the taper, screw down the J-tool and tighten to 20 N-m. Remove them and install the nut and tighten to 48 N-m. I don't think the tool torque is critical. Just the torque for the actual nut. You can pretty much emulate this with an impact. Just set he impact to minumum torque.

I've never seen these tools in person. I think the ID might have a clearance for the end of the tapers so the tool pulls the taper onto the tapered hole.

View attachment 162166

Found an image of one that shows the clearance for the nut/taper end.