Stromius

It's odd that after probably 26 years, it's time for the bolts to loosen and create a pucker effect whilst driving to fetch junior from school.

Low speed, noticed a whirr at any RPM's above 1500....can you say U Turn!

Garaged it and found this:



It's tight quarters but there should be 3 bolts there (M6 x 12mm btw) but one is missing and two are loose thus the cocked pulley on the pump snout.

I tighten the two bolts and find a short M6 bolt to fix the problem or so I think. #3 bolt won't go in. Crap... wtf snapped bolt too??!!

Removed pulley after tightening a bolt to find this:





I am thinking of a Dremel to carefully grind off the offending end. Besides ruining the shaft (probably won't matter that much) any downsides to my approach. Given the tight quarters, there aren't many options besides removing to work on it at the bench.



Update: necessity is the mother of invention. Dremel is too tight so used a 10" metal blade for my sawzall and built up my left forearm to trim off the stub. Plugged it back together and

Pagnobito

Not the first time I've seen that, did you refit with 3 bolts?

Mrmerlin

I would suggest that you get a small diameter left handed drill bit,
and remove the pump and reservoir from the mounting points,
drop it down so you dont have disconnect the lines.
carefully drill into the remaining stud, , it should unscrew.

I will guess that the remaining part of the bolt could also come out and cause further damage to the pump

MFranke

Both my S4s had this happen in last two years and those bolts were never touched by anyone that I know of. Must be age related one car has more than double the miles. One S4 I caught early and just tightened. The other had a broken bolt.

If it's been awhile take the opportunity to remove the pump and rebuild it. You have to loosen up the accessories there anyway for the belt.
Add a fresh hose and filter too. It's easy job and cheap parts. As a bonus you will be able to remove the broken bolt much easier. I used a dremel to make a notch to unscrew it, but this was probably not needed unless really corroded. It came out real easy. It is the same bolt you find on your air pump if I recall correctly, so if air pump is removed just salvage one from there.

Stromius

Thanks all... its back together but I'll bust it out next week for a rebuild.

PSA: check that those pulley bolts are tight.

GregBBRD

There's a hollow dowel that gets pushed back into the flange that needs to protrude enough to pass through the pulley. This dowel absorbs a lot of the load. With it pushed back in, it's almost impossible to keep the stock pulley bolts from shearing, unless the car never gets close to the "lock" at either side.

I've had customers that turn their steering to lock (and hold it at lock) which will shear off the stock hardware frequently. For those customers, I began using 12.9 grade hardware, increased the torque, plus fitted a solid hardened dowel. That solved the pulleys coming loose, but would not keep the racks from blowing out the seals...

After I replaced one customer's 3rd rack (under warranty) I told him he was on his own. He now makes a three point turn into his "impossible to get into" parking spot, instead of forcing the power steering and making it into that parking spot in one try.

No more problems!

Stromius

Thanks Greg!

That dowel at least in my case was a glorified rivet near as I can describe it. Maybe protruded 1/2mm (somewhat visible in last pic). Will definitely go easy until I get the p/s pump on the bench to address.