When fluid leaks from where a metal line inserts into a hole sealed by rubber it is intuitive to me that the rubber has a failure -- not the metal. In your case you have already replaced the line, therefore the cylinder has got to be the problem. I have seen this failure before, and it generally can not be discerned by just looking at it.

My advice is to purchase a used cylinder. I have one to sell you, but it will cost an additional $50 to first send it to Dennis Ficken to be resealed. You can also find cylinders on eBay.

If you want my cylinder, then PM or email me with a fair offer. I will surely accept it.

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For Sale: many used R129 parts from a white '92, black interior. Send email if interested.