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  #1  
Old January 17th, 2022, 06:10 PM
Jim A Jim A is offline
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Default Wheel cylinder

This probably should be in the brake forum, but the problem arose yesterday on my '60 1500 RWD..
After getting my clutch finally fixed (so I can go), I have begun on a front brake problem (so I can stop).
The right front cylinder is completely crudded up with a 60 year brake fluid/moisture cement.
I recently re-did the back ones (for leaks, not stuck) and I think the cylinders are available at reasonable cost.
The 3/8" bolts that hold the cylinder to the backing plate are refusing to loosen, however.
It may take removing the whole plate to get to them unless someone has a great idea.
I thought I may have rebuilt them 40 years or more ago, but now doubt it, since the pistons cannot be removed without the taking out the cylinder, because of a bracket that has two ears extending over its ends.
I am stuck, but not stymied and if anyone has recently worked in this area and has nothing to do this MLK Day, chime in.
Thanks
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  #2  
Old January 18th, 2022, 02:43 AM
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AZKen AZKen is offline
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Default Re: Wheel cylinder

If you are talking about the two bolts holding the cylinders to the plate. Turn them until they either loosen or break off. Bolts are cheap. Buy new cylinders. Done.

Use an impact wrench so you don't wallow or damage the holes.

Last edited by AZKen; January 18th, 2022 at 02:49 AM.
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  #3  
Old January 18th, 2022, 10:26 AM
Prowbar Prowbar is offline
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Default Re: Wheel cylinder

I've found that the cast iron of the wheel cylinder is really soft and the thread engagement is not that long. It should be fairly easy to snap off the heads of the bolts as you're replacing the wheel cylinder anyway. If the bolts are rusted to the backing plate a couple of whacks with a hammer and punch should loosen them up. Good luck.

The brake line and nut came out in one piece?
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Old January 18th, 2022, 06:09 PM
Jim A Jim A is offline
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Default Re: Wheel cylinder

Thanks for the replies.
When I mentioned recent familiarity, it was because it is easy to forget how nearly inaccessible the two bolts are. The only tool usable is a 3/8" wrench with the box end marginally the better.
One problem is that these bolts have had 60 years to weld themselves in place and another is that they seem to be 11/32", so the 3/8" (12 point) simply doesn't get a good grip. A 9.5mm six point might have been a choice
With a 3/8" six point wrench pushed firmly on the bolt head, I finally got one of them to round off. That so often feels at first like loosening!
So I think I have used up loosening options. Removal of the backing plate for a more brute force attack is tempting, but rhis requires getting the three big bolts (two castellated) off the steering structure, seriously buried in 60 years of grime.
The approach I think I will try today is drilling out the bolts from the front of the cylinder.
As noted, the bolts and the old cylinder are sacrificial.
One problem with old vehicles (though younger than I) is that 2 hour jobs so often aren't.

Prowbar: I am not sure what you mean by "brake line and nut."
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Old January 18th, 2022, 08:35 PM
Prowbar Prowbar is offline
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Default Re: Wheel cylinder

Sorry I meant to say did you get the brake hose removed from the wheel cylinder. But then again that does not really matter as it will be replaced also I assume.
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Old January 18th, 2022, 10:33 PM
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Default Re: Wheel cylinder

Hard to tell without pics but I don't see a big "access" problem. Cut the bolt heads off with angle or die grinder or sawzall now that you have rounded the heads Go nuclear or go home!

You only have to cut half way then air chisel/hammer chisel the rest. Smash it. Be psycho on it. From 1 to 10................it's a 1

Last edited by AZKen; January 19th, 2022 at 12:26 AM.
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  #7  
Old January 19th, 2022, 04:55 PM
Jim A Jim A is offline
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Default Re: Wheel cylinder

Ken: I know you like pictures, but the bolt heads are so securely tucked away good imagery is not on. Likewise access for the grinders you mention.
Best suggestion is that you go out and look behind any of your front wheels to see the problem.
To avoid the various possibilities, each with drawbacks, for removing the old cylinder, I went for cutting the tip off one of the protective "ears" on the backing plate.
This allowed me to drive out the old components and give the cylinder bore a good cleaning and inspection. This showed a sound bore that got even better with a light honing.
Since rebuild kits are no longer available, I had to buy a new complete unit. I was surprised to find both my favorite local independent parts stores had one in stock.
So I removed the pistons, seals, spring and end covers from the $40 beautiful new assembly and transplanted them to the old one.
So far, it looks like the best fix, if not for a 1000 mile cross country race, but fine for hauling this year's hay, etc.
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