1968 Cornet R/T Master cylinder - manual 4 drum brakes - Ebay MC clone part question

[Mory]

I just purchased a new aftermarket Master Cylinder off Ebay that looks identical to my original. I found that the push rod and rubber bushing slide into the piston with no resistance and will easily pull out. I checked with t a caliper and the new piston inner bore is the same size and the rubber busing. Also, there is no machined slot inside the piston bore. I contacted the seller and he said he sold 77 of these with no reported problem. Also, I found the piston retainer with rubber sleeve mounting holes are now metric. The loose piston/bushing has to be a safety issue being the brake light switch would be the only thing preventing the push arm pull out. Has anyone installed a manual MC without a secured push rod bushing? Is it possible the power brake MC can use this? I wanted to run it past the forum experts. Thanks

 

[R/T Boy 67]

Manual brakes should have the groove for the retainer. I wouldn't use that master for manual brakes. I wonder if your original piston would fit with the cups off the new master?

 

[Mory]

I thought about using my old piston with seals from new but a little concerned with the metric threading on the casting. Any chance there could be an issue?

 

[Don Frelier]

I think I would return it.

 

[Mory]

I have it boxed up and waiting for seller to respond. He wants me to pay shipping and I told him the part is not correct so I shouldn't have to pay. I'm concerned that he sold 77 of these with no issues reports. Too bad, the MC does look good. Either way its going back.

 

[sam dupont]

Get a half dozen padded flat rate envelopes and use them all if you can. Look at it as the same as driving across town for a waste of time and fuel. It's less than $8 to ship it back, then look for threads here for opinions and options to source the best master for you.

 

[gtx6970]

Ive used 2 of them . one on a manual brake car and one on a power brake car

No issues with either

 

[Mory]

Ive used 2 of them . one on a manual brake car and one on a power brake car

No issues with either

How did you get the bushing to lock in the piston? My push rod / bushing slide in and out of the piston with little or friction. Did yours also require using metric screws for the piston retainer/boot? I'm sure the brakes would work but concerned with potential of the push rod not secure.

 

[gtx6970]

How did you get the bushing to lock in the piston? My push rod / bushing slide in and out of the piston with little or friction. Did yours also require using metric screws for the piston retainer/boot? I'm sure the brakes would work but concerned with potential of the push rod not secure.

One of the cars was a power brake car so no issues with the rod retention.
2nd car was manual brakes and my original rubber sleeve locked in with no issues .
I didn't have the rear dust boot to worry about. Bolted it on and away we went.

 

[Mory]

One of the cars was a power brake car so no issues with the rod retention.
2nd car was manual brakes and my original rubber sleeve locked in with no issues .
I didn't have the rear dust boot to worry about. Bolted it on and away we went.

Thanks for the response. The MC I bought looks exactly like my original but the piston hole is several thousandths bigger than my original. The rod/bushing will not lock and can slide in and out with little resistance, also dust boot screw threads are metric so I would need new screws. I'm sending it back. I hope the other 79 the seller sold didn't have the same issue.