Bill Harmatuk

30 Chrysler Brake Cylinder Question

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Ok

My original brake cylinders were screwed up by a well known rebuilder. The bleeder seat on the cylinders was destroyed by an over acheaver on the bead blaster, when they cleaned them up prior to re-sleaving. Cut the machined seat for the bleeder valve all to............. Sent them back. They installed heli-coils and what ever, and they still leak from the bleeder valves. Not looking back. I'm moving forward. Cost me a lot of time which is expensive.

 

THE QUESTION

I have a new set of 4 brake cylinders that have 1 1/4 and 1 3/8 bore. 248.00, thank you.

My old brake cylinders were a straight 1 1/4 bore.

I don't think it makes a hill of beans differance in regaurd to the stepped bore. . Am I wrong?? Hope not. I'm using the original master cylinder.

Which way is the larger bore on the brake cylinder supposed to be orientated.?? I hope the front shoe. Thats the only way it can bolt up.

 

Yes, I'm using silicone brake fluid from Cartel. 

 

Thanks in advance

Bill H

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There will be more force on the 1-3/8 end in the ratio of the area of 1-3/8 to 1-1/4 = 1.21. You MUST have the same on the other side if you do that. The larger bore goes on the leading shoe which is on the front.

 

Is the master cylinder big enough? it will take extra fluid to operate the larger cylinders.

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I think you're going to find the bolt patterns are incorrect on two of the cylinders.  I went the same route and discovered the pattern is different on the front and rear.  Luckily, my originals were resleeved with out any issues.

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Were the wheel cylinders re-sleeved with brass ? 

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The new cylinders were not re-sleeved with brass.

They are new.

I dis-assembled them last night and checked the bore for rust etc.

Taped up the ends of bore, cleaned and painted exterior with Eastwood Brake Gray paint.

 

I dry fitted this morning and they all fit. Large bore to the front and all bolts match holes in the backing plates. (I must be living right).

It appears that the cups were pre lubed from the supplyer. I will add a little more silicone grease to the cups before final assembly.

I'm happy. Moving forward. I can"t believe I got this lucky.

The cylinders were purchased off of E Bay. 

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I had a set of 30s mopar brake cylinders sleeved with brass       when I got them back the bleeders leaked     don't know why    sent them back they put fee male bleeder sleeves and sealed with lock tight blue and smaller male bleeders      worked fine       why would you put wheel cylinders with stepped bores if your car does not call for it ?    if you send a picture of the original cylinders I may have new ones

Edited by broker-len (see edit history)

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