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My Matco Master Cyl leaking again MC4?

riobison

Well Known Member
Matco Master Cyls leaking. Just confirming that on my 9A that its the 0-Ring Rebuild Kit MC-4 that's needed from ACS?
And not the MC4A?
My stickers are gone so I have no idea.
Thanks
Tim



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MC-4 REBUILD KIT

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06-02998

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In addition to the rebuild kit, order a new shaft. They leak due to side loading of the shaft which wears the seal. A new seal will not last as long as it should unless the shaft is replaced. Some have had good luck with polishing the shaft but for my money I just replace it.
 
In addition to the rebuild kit, order a new shaft. They leak due to side loading of the shaft which wears the seal. A new seal will not last as long as it should unless the shaft is replaced. Some have had good luck with polishing the shaft but for my money I just replace it
Probably a good idea as this appears to be an ongoing problem.

Is this an MC4 or MC4A? Part # for the shaft?

Thanks Tim
 
I’d like to help but it’s been a long time since I had to do mine and don’t want to steer you wrong.
 
Probably a good idea as this appears to be an ongoing problem.

Is this an MC4 or MC4A? Part # for the shaft?

Thanks Tim
If you don’t get an answer, i will go back to me acs order archives. I thought it was mc4, but just can’t recall.
 
MC4

Part# 06-02998
MFR Model# MCMCRBD4

This was the rebuild kit I ordered and it worked
Thanks, I do appreciate the help. 60 hrs ago I changed the seals and its started again. I didn't see any scarring on the shafts but I will change them as well. Its such a pita on working under there.

Thanks again

Tim
 
Thanks, I do appreciate the help. 60 hrs ago I changed the seals and its started again. I didn't see any scarring on the shafts but I will change them as well. Its such a pita on working under there.

Thanks again

Tim
Thats odd. It is pretty straightforward to reassemble, but wonder what would cause that. My shafts looked decent, but I chuck them in a drill and hit with 600 grit. Recommend you try that. Also make sure you do not assemble it dry. Each piece of rubber needs a bit of fluid on it when reassembling. You can trash the orings in a few strokes when dry.
 
Ordered MC-4 Rebuild kit and Shaft MC -4F, 2 of each. It was aligned as best as possible with the washers, may need to try the all thread option or something similar. Thanks for the help guys.
 
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