The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - Brand new master cylinder leaking from the lid

76JimmyBlue · 08-27-2023, 04:32 PM

Hi everybody, having a really frustrating problem here. I replaced the original master cylinder on my '76 K25 with a new AC/Delco one and it leaks from the lid at the gasket. I swapped the bales from the old one and it seems to hold the lid tighter, but still leaks. Either the gasket isn't thick enough or the lid is bent or something. Worst case is the machining of the casting was done poorly. Doesn't look as good as the original M/C, but a straight edge doesn't show any gaps that would cause a leak. Getting REALLY angry at this truck so please, any help is appreciated!

08-27-2023, 04:32 PM	#1
76JimmyBlue Registered User Join Date: Jun 2022 Location: Bothell, Washington Posts: 25	Brand new master cylinder leaking from the lid Hi everybody, having a really frustrating problem here. I replaced the original master cylinder on my '76 K25 with a new AC/Delco one and it leaks from the lid at the gasket. I swapped the bales from the old one and it seems to hold the lid tighter, but still leaks. Either the gasket isn't thick enough or the lid is bent or something. Worst case is the machining of the casting was done poorly. Doesn't look as good as the original M/C, but a straight edge doesn't show any gaps that would cause a leak. Getting REALLY angry at this truck so please, any help is appreciated!