I am trying to get my brake booster off the firewall and all nuts came off except the upper passenger side which now pretty rounded. Any ideas on how to get the nut free without cutting the stud? The issue is clearance and only an open-ended wrench seems to fit in the tight space.

Thanks
Sean

 

vice grips

self tightening wrench or enclose openable line wrench:

http://www.grainger.com/product/PROT...set&s_pp=false

http://cgi.ebay.com/ebaymotors/NEW-G...item5afdb40f91

http://www.ebay.com/itm/NEW-WILLIAMS...item3efa88b12d

cutoff wheel used judiciously

 

round nuts always yield to a small pipe wrench for me. Several stores hereabout have closed end wrenches with that 'nut-off' spiral on them ... but if open ended is your only option, I suspect you're down to Dremel territory.

 

Guys,

I will to see if I can get a small pipe wrench back there but from what I remember it is really tight. Do you know if the stud can be replaced easily should I choose to cut it?

Thanks
Sean

 

If you can soak it with pentrant and then use a small vicegrip or channel lock.

 

Ive used larger versions on locking lugs nuts where the key is long gone, and they work well.

 

The stud is actually a bolt with a flat, round end that is spot welded to the inside of the firewall. If you crawl under the dash and look at that area you will see the backsides of the studs. The spot weld on one of mine broke loose back in the 90s so I just used the remaining three bolts to attach the booster. Then when I got a replacement booster a few years ago I used a regular hex head bolt in that location - slipped it in from under the dash and used one of those flat nut thingies like you see on brake rotors to hold it in place. It's slightly more difficult to tighten that one but how often are you removing the brake booster?

If you can't get the nut off, you might be able to grind down the round backside of the stud so it will pull through the firewall. Then if you have access to a welder it would be simple to spot weld a regular bolt in its place.

 

Actually, the stud is welded to the dash brace that the brake pedal pivots from. You can remove the entire brace once the booster is off. Unfortunately, you may need to drop the steering column also.

 

Thanks guys. I will give it a try with a nut extractor first then if that doesnt work the job will get a bit more labor intensive....

Sean

 

You may want to re-install the other bolts and pull everything in tight against the fire wall. Maybe take some pressure off your rounded nut.
Tom

 

Heat it red hot with a acetyhlene torch should help it lose, be careful with the flame. If you try to break ithe rusted nut lose unheated with a pipe wrench you probably break the stud.

 

I had this issue and tried a nut-cracker. Did not work as only half was split, so I cut just the nut with a carbide bit on a dremel tool and eventually twisted the nut off clockwise. Just do not cut the stud threads!
I will share the fun here:
https://classicoldsmobile.com/forums...tml#post298896

 

Ah, that makes sense. Thanks for the clarification. I didn't disassemble it to the point of figuring out what it was welded to.

 

Well I went to Sears to get a set of nut extractors as well as a small pipe wrench. Neither worked after about 2 hours of messing with it. I then tried the Dremel with a metal cut-off disk and it worked pretty well until I got to a point where I could not cut any further without risking damage to the stud. I am pretty close to just cutting the stud flush and re-welding a new one later. Stay tuned...

 

Dremel...keep working, try a different bit if the wheel won't work. Sometimes a new wheel will get in places a used one won't, and vice-versa. Welding a new stud is not going to be a picnic, either!

 

If you've got a good slot cut, put a chisel in it at an angle and give it a good wallop with a BFH. You'll either spin it loose or break it off ... either works. You don't happen to have access to an air chisel, do ya?

 

Great build thread. Nice attention to detail