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Problem With Brakes After Converting To Dual Ms On 66

  • Thread starter Thread starter slymongoose
  • Start date Start date Oct 2, 2014
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tos

Founding Member
Apr 27, 2001
896
68
59
Cincinnati Ohio
Oct 7, 2014
#21
  • Oct 7, 2014
  • #21
Also I noticed you said you upgraded to 5 lug on a 6 cyl car but that video you posted looks like that backing plate and spindle have been on there awhile. Did you use the old ones that were already on there. If that's the case - 6 cyl cars had a 9" ID drum and 8 cyl had a 10" drum so you could be using 9 inch pads with a 10 inch drum?
 

slymongoose

New Member
Oct 2, 2014
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captain cook
Oct 24, 2014
#22
  • Oct 24, 2014
  • #22
finally got around to putting a new master cylinder on last weekend. works great. i guess i just had a bad new part..
 

bartl

Active Member
Feb 4, 2001
218
8
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68
West Rutland, Vermont
Oct 25, 2014
#23
  • Oct 25, 2014
  • #23
"R" goes on the PASSENGER SIDE. It does NOT indicate a "right hand thread" on the adjuster "star wheel", it indicates "right side", just like on the adjuster lever. That said, I doubt it's the cause of your problem, unless you backed it all the way off, and then I'd have my doubts. It's possible you have the wrong hold down pins (too long), the wrong hold down springs (too weak), the wrong shoe "pins", the little forked pins that connect the wheel cylinder cups to the shoes (too short), the wrong shoes, or the wrong wheel cylinders. When properly installed, it is pretty much impossible for a master cylinder to generate enough pressure to "blow out" a wheel cylinder.
 

bartl

Active Member
Feb 4, 2001
218
8
29
68
West Rutland, Vermont
Oct 25, 2014
#24
  • Oct 25, 2014
  • #24
tos said:
Also I noticed you said you upgraded to 5 lug on a 6 cyl car but that video you posted looks like that backing plate and spindle have been on there awhile. Did you use the old ones that were already on there. If that's the case - 6 cyl cars had a 9" ID drum and 8 cyl had a 10" drum so you could be using 9 inch pads with a 10 inch drum?
Click to expand...
THAT will definitely do it.
 
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