Bushing Installation (Control Arms off the Car)

May 2009 Update: A writeup at Honda-tech.com says that the ball joint press part (with OEM #27023 embossed on the case cover) that Autozone rents works fine for installing the bushings. See http://honda-tech.com/showthread.php?t=2575490. Otherwise, try what is described below.

Clean the insides of the control arm bushing holes with Emery paper and maybe a bit of the penetrating oil "PB Blaster." Wipe the arm free of dirt and oil. With a hammer and socket that fits the outer sleeve diameter almost exactly, tap the bushing into place. Hammer evenly, so the bushing advances as levelly as possible.

Advance the bushing via hammering until you can use the sockets-bolt-nut-washers method described above or, in the alternative, a puller. I found a clamp I made using the $11 (in 2006) Harbor Freight puller at the right required much less labor than the sockets-bolt-nut-washers method if you can keep the clamp well aligned with the centerline of the bushing-arm assembly. Harbor Freight's puller set includes a 3/4-inch diameter, fine thread, apparently high grade pressure screw.

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If you use the puller, then you will also need a lower yoke. I used some junkyard scraps judiciously selected for this. In the alternative, one can just buy a second puller. Similar puller sets with slightly smaller pressure screws are also sold as "harmonic balancer pullers" at Autozone and Pep Boys, at similar prices. The Harbor Freight puller's 3/4-inch diameter pressure screw, with two other 3/8-inch, high grade bolts (True Value hardware) passing through the yoke and straddling the control arm, was very effective at pushing the bushings in, with one caveat: Any tilt to the setup, along with applying excessive torque, is likely to strip the pressure bolt threads. I installed two-and-a-half bushings using fairly light force on the wrench when I got overambitious, felt the force needed to torque increase, and kept going. I could see the pressure screw was tilted. Needless to say, one 3/4-inch pressure screw is stripped. If I had stopped and re-aligned the yokes, sockets, scraps, etc., things might be fine.

For either the sockets-bolt-nut-washers method or using a puller, any doughnut shaped scraps you can find will be helpful, too. I collected many such scraps from junkyards in advance. The bushing may or may not slide in fairly easily. I used mostly a 1.5-foot pipe extension on my wrenches and was not applying anywhere near my whole body weight when advancing the bolt or pressure screw. Also, I think applying PB Blaster to the bushing sleeve-control arm interface throughout does help. An hour or so may be required altogether, once you have figured out the right sockets, scraps of pipe, Grade 8 bolt lengths, washers, etc. to use. If you find you need more than a 1.5-foot pipe extension, then the torque you are applying is very close to stripping the bolt's threads. At a few points, a five-foot pipe extension on my wrenches was working fine, advancing the bushing into place, but I also managed to strip two 3/8-inch bolts in the process.

The 3/8-inch bolts never yielded in tension (that is, pulled apart). This suggests the force the sockets-bolt-nut-washer setup applied to the bushing was probably less than seven tons, by my calculations using various, basic bolt formulae and theory. The bolt/nut threads are not supposed to strip until about nine tons are applied. I figure I had tilted the nut somewhat when tightening, causing the stripping to occur. The washers and other doughnut shaped items beneath it were in fact yielding (= bending) somewhat, causing things to get a little uneven. (The sockets by contrast held up well.) So with the nut under load and tilted relative to the bolt axis, at high enough loads, the threads would strip. Check often that the centerline axes of the bolt, bushing, and control arm hole are as perfeclty aligned as possible. Tapping with a small hammer at times can help ensure this.

I think if I had taken more care to keep the sockets-bolt-nut-washer setup straight, the two bolts might not have stripped. New and tougher washers, or bolts of easier lengths with which to work with the sockets I had, might also have prevented stripping.

I tried putting the new bushings in the freezer overnight and heating the control arm in a 200 degree F oven for an hour. I think this helps. A propane torch would be better, so the arm is heated only locally. One may use Tempil sticks to gage the temperature of the arm accurately. One wants to be aware of how high the temperature is. If the temperature is too high, then the arm's structural integrity risks being compromised. (Thanks to JT of the honda newsgroups for this step.)

Lessons Learned
  1. A 12-ton shop press would likely successfully and easily install new bushings. I do not think a 2-ton press would always be enough, based on my experience and calculations and reading about others trying 2-ton presses.
  2. Even if one goes with the shop press, one will have to buy the sockets or other bushing press accessories.
  3. Based on my calculations of the tons of force required, I have doubts about the wisdom of using any hammer to beat bushings into an older control arm already scuffed up from bushing removal. One has to possess a great deal of upper body strength and a lot of endurance, not be susceptible to heart attacks, etc. I think that the force the two screw methods (sockets-bolt-nut-washers-etc. and puller) offer is in fact much higher than that achieved by blows with a huge hammer. Applying hammer blows also risks the integrity of the bushing and control arm. Strongly consider using the amazing leverage of one or both of these screw methods in place of a hammer.
  4. Snap-on Tools sells a puller with a 3/4-inch diameter pressure screw and two, hefty jaws rated at 10 tons. By my calculations a factor of safety of over two is built into this. This does not mean you should try to apply 20 tons with the Harbor Freight 3/4-inch diameter pressure screw puller I describe above. For one thing, the two 3/8-inch diameter bolts I used with the Harbor Freight puller are not nearly as hefty as the jaws on the Snap-On Tool, so the Harbor Freight puller's pressure screw takes much more of the load. The likelihood of a little tilt stripping its threads is higher. But I think my use of the 3/4-inch diameter pressure screw puller and Snap-On's specifications do tend to confirm that around seven to twelve tons of force will install the bushings easily.
  5. Buying new arms with bushings already installed is also an option. The rear arms for a 91 Civic are less expensive than the front ones.


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