OK, I don't get it. I'm trying to remove the rear caliphers (so I can rebuild them and rework the emer-brakes) and I don't have a socket that will fit the bolt heads. 9/16 is too small and 5/8 is too big. 15 mm is too small as well. The only one that seems to fit the best is 16 mm, but that even feels like it has a bit of slop in it. I fear I've already wrecked one bolt head and don't want to round any more. All I had in the tool box at the beginning of this adventure were 8 and 12 point sockets, but have since added 6 point in all of the sizes mentioned above looking for one to fit. Anybody out there got a 19/32 or a 15.5 mm...??? I'm open to any other removal suggestions as well.

Thanks!

Jim, I'm pretty sure that a 5/8 was a perfect fit on mine. Maybe they changed it though by the time '77s rolled around. I had to use an impact gun to get mine off as well, but I'm sure it was a 5/8 because I had to take them off and put them on a couple times after trying to rebuild them just over a month ago. Sorry its not working for you.

Dale,

How the heck did you get an impact wrench up in there? Sure doesn't seem like there would be enough room for one. The 5/8 - 6 point socket I bought seems to be pretty sloppy to me. The 16 mm - 6 point is a little snugger, but still not snug enough. Maybe I'm just over reacting after doing a pretty good job of messing up one bolt head already with the 8 and 12 point sockets I had in the tool box. Been hosing them all down with penetrating oil so hope that helps free them up some.

Jim O.

Jim,
I put an extension bar on it and it fit on one better than the other, but they both came out. I tried with hand tools and even after soaking in WD-40 they wouldn't budge.

Extensions I have so will give it a try. Maybe a wobble joint will help some too.

Thanks!


Jim O.

I can tell you definitively that 15.5mm does not exist. 16mm is the standard across flats for ANSI & ISO M10 thread diameter hex head bolts. The Germans (DIN) use 17mm for the same M10 thread. Pretty sure you have a worn or slightly undersized 5/8" given the origin of the bolt in question. Stick with 6-point to avoid rounding. I can check with Armstrong or Proto to see if the make a tighter tolerance 5/8" (but I doubt they do).

PS - this is what I do for a living -- METRIC fasteners & industrial supplies -- check out www.metricmcc.com.
~ Joe

|UPDATED|7/31/2002 9:51:26 PM|/UPDATED|

Joe,

Thanks for the info. The quip about the 15.5 MM was just a joke, but a 19/32 doesn't sound that too out of line does it? I'm looking at having to destroy a 15 MM as that seems to be the only way I'm going to get one bolt out - beat the socket on there. Don't know of any vise-grip type tool that will work in close quarters.


Jim O.

Take it from experience, if a 15 mm is what you need to use to get the bolts off then use a 15 mm. Worst case is you chew up a socket and have to spend a couple bucks for a new one.

My bolts were so old and stuck that I would have bet large sums of money that the bolts and the bracket had bonded together to become one piece of steel.

2 cans of lubricant and 3 days later I was finally able to drill my way to freedom.

Also, you did the right thing by getting the right point socket for the job.

Good luck.

Also remember that rust makes bolts bigger then smaller!
( bigger as the rust forms on the bolt, smaller as the bolt rusts away )

You may have to hammer on a socket, take the bolt off and then hammer off the socket...

For my 72 and my friend's 73, 5/8" is definetly the correct bolt. Perhaps yours got worn or stripped. once they are removed (good luck) get some grade 8 bolts that are 5/8" and the proper length and install them. Metric didn't start until the late 70's.
Gary