From: Wally Plumley [wplumley@bellsouth.net] Sent: Thursday, September 06, 2001 8:38 AM To: 928 Subject: [928] Re: Ball joints At 07:53 AM 9/6/01, Dave Ash wrote: >Has anybody out there gone through the process of replacing the front >upper ball joint boots? If so how did you take the joint apart? Pickle >fork,special tool,or wack the heck out of it? Thanks for any help The problem is that a precisely machined taper will stick in its mating tapered seat. A pickle fork (wedge tool) is likely to damage the ball joint. A ball joint removal tool (available at loan or rental at some auto parts stores) will remove the joint stud. Another way that usually works is the two-hammer method. Loosen the nut on the tapered stud, so that there is space between the nut and the arm. Put the largest chunk of steel (such as a sledgehammer) against the spindle where the stud goes thru. Whack the spindle as hard as you can with a big hammer on the opposite side. What you are trying to do is to slightly and temporarily distort the tapered seat in the top of the spindle, so that the stud will be spit out. This method will work on most tapered joints. Wally Plumley 928 Specialists From: Wally Plumley [mailto:wplumley@bellsouth.net] Sent: Friday, August 16, 2002 8:40 AM To: 928 Subject: [928] Re: back to bjs-- ball joints At 08:08 AM 8/15/02, Steven M . Tucker wrote: >Question for DIY ball joint revision, >After balljoints are changed, you can't really drive the car because the >alignment is way off. >But you can't align the car after lifting until the suspension is settled. >So do balljoint changes require the manual pull-down routine prior to >alignment, or if carefully done >is it usually close enough that you can putter around for a few miles to let >it settle? While you have the car up in the air: 1) Check the movement on the caster eccentrics, and max out the caster. 2) Adjust the camber eccentric to mid-range on both sides. 3) Adjust the toe for about 1/8" toe-in at the tire surface. Drive it for a couple of miles, and check the toe without lifting. Set it close to zero, with just a little toe-in. Take it for a proper alignment. Neither caster nor camber is a major tire-wear angle in the short term. Toe is. Wally Plumley 928 Specialists From: Wally Plumley [mailto:wplumley@bellsouth.net] Sent: Sunday, May 11, 2003 6:59 PM To: 928 Subject: [928] Re: Can you replace the lower ball joint boots? At 04:47 PM 5/11/2003, Martin Bishop wrote: >It would be a piece of cake to put new ones in with everything torn down. >I don't want to replace used ones with used ones. On one side the boots >were fine. A little dry rot, but holding in the grease. The other side >where they were dry (no grease left) the upper is somewhat loose. Not >real loose, but somewhat loose. Now that it is full of grease with the >new boots, they seem OK. The thing is I don't want to go thru the effort >to replace them with used ones since $350 is a lot for a band aid. I >would prefer to replace with new, but at $1500 for the pair, I can wait. >And at that amount I can have someone do it for me. Let the dealer get >the torque right on those. > >Since this is an 88, I am unaware of rebuilt ones available. It sure >would be nice to get some "love" from Porsche on these VERY expensive >upper ball joints. > >Martin The ball joints are very different in their wear patterns and replacement requirements. The lower joints support the weight of the car as well as hold the uprights in the proper position. As a result, the ball is pulled (or pushed, depending upon the year) into the socket, so looseness has virtually no effect on the function of the joint - at least until the joint fails. Most American cars have specs on how much looseness is acceptable, and some could have as much as 1/8" of movement allowable in the joint. I don't remember ever seeing a spec for the lower joint on a 928. The upper joints serve only to maintain the position if the upright. Since there is no weight carried or preload, any looseness will result in some uncontrolled movement of the upright. However, if the ball has no noticeable play in the socket, the joint should be acceptable, provided it is clean and lubricated. Wally Plumley 928 Specialists From: Jay Kempf [mailto:jkempf@tds.net] Sent: Thursday, August 28, 2003 10:08 AM To: 928 Subject: [928] RE: front end > OK, I"ve searched the archives and found posts relating similar > problems...but never the subsequent solutions. > > I've got a definit 'pop' under the driver's footwell, sounds as though its > inboard of the spindle assembly. I should stipulate that I am > aware of the > balljoint supercedence, this sounds like a much 'lighter' or > 'tinier' sound > than I would expect to hear from a worn/failing balljoint. > > After poking around underneath myself, the noise was gone for a few miles > and gradually returned with increasing frequency and intensity (something > about unloading front suspension made it go away temporarily?). I took it > to a European specialty shop, and the tech said that I needed a new rack > because there was some end play in the 'bushings' at the junction of the > rack and inner tie rods. > > Does this sound right? I thought the bushing that typically > failed were at > the mounting points of the rack to the frame? Is this something > that might > be remedied by replacing the inner or complete tie rod? Or are > there actual > bushings at this location and if so can they be serviced? > > Again, the noise was gone when I first started to drive home and slowly > reappeared/intensifying as I drive the car. > Finally got a couple thousand miles of driving this 83 Euro under my belt, > was hoping that this would be low-key. > TIA > ST Large Channel Lok pliers applied axially to the upper ball joint. If you can squish it vertically (shortening it) then it is loose. They will make exactly the noise you describe. Cannot be tested by prying cause it is internally spring loaded. Jay K. From: Wally Plumley [mailto:wplumley@bellsouth.net] Sent: Saturday, August 30, 2003 6:54 PM To: 928 Subject: [928] Re: balljoint At 12:46 PM 8/30/2003, sertan wrote: > How can I understand balljoint failure ?How can ý check it?When I press >the brake pedal hard (panic braking) My car moving head left to right. > 86 928s 4,7 16v Thanks To check the lower ball joints: Jack the car with the jack placed on the lower suspension arm as close to the lower ball joint as possible. When the tire is off the ground, use a pry bar under the tire to lift the tire and check for movement in the ball joint. Some movement is acceptable. To check the upper ball joint, use a very large pair of slip-joint pliers to squeeze the upper suspension arm down on the spindle and check for movement between the suspension arm and spindle. There should be almost no play in the ball joint. Other things that can cause darting under braking: Loose tie rod ends, either inner (at the steering rack) or outer (at the steering arms at the wheels). Loose steering rack support bushings. Poor alignment - if the car is jacked before or during the alignment, the alignment is wrong. Incorrect tire pressures. Loose front wheel bearings. Wally Plumley 928 Specialists From: kjcracer@yahoo.com [mailto:kjcracer@yahoo.com] Sent: Sunday, August 31, 2003 8:02 PM To: 928 Subject: [928] Re: Upper Ball Joint I wrote about this a decade ago. The boot from an '86 Audi 5000 Turbo works. I found out the old fashioned way...in trying to work on the suspension with a pick folks...not the recommended tool...torn boot. I hear that Porsche doesn't sell a replacement boot, and since the car hasn't been driven at all, I know there's not road grit in it (yet.) Off to the dealer...which also happens to be an Audi dealer. I put the torn boot down on the counter and asked them to get out their Audi replacements. Voila...here's one that looks like a fit. Worked fine. Passed that one on in Pano, long ago. If it's been "open," and driven, there is the risk of road grit grinding the ball joint apart...a nasty failure on the road...please be conservative about this. Kim