CorvetteForum - Chevrolet Corvette Forum Discussion - 1992 Master Cylinder ABS Prime Nipple Repair

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1992 Master Cylinder ABS Prime Nipple Repair

Finding a replacement for the '92 to '94 reservoir is near impossible, and none of the aftermarket sources provide the ABS piped reservoir, even with the pruchase of the entire master cylinder. I found one source, and they wanted $139, just for the reservoir......No thanks!

After not finding a repair thread for the '92-'94 master cylinder reservoir broken ABS prime nipple, I figured I'd share how I fixed mine.
I found an 1/8 to 5/16 pipe to hose adapter (Dorman 072020BP) at my favorite parts place. I measured the threaded end of the adapter, found the closest drill bit, and expanded the hole to match. I removed the drilling debris from the reservoir, and cleaned the bore with alcohol. Then I used used two-part epoxy on the adapter threads, as well as around the hex of the adapter, to fix it to the reservoir. The resulting fix is much stronger than the flimsy plastic pipe and works well. :cheers:

https://cimg1.ibsrv.net/gimg/www.cor...634bb40f03.jpg

https://cimg2.ibsrv.net/gimg/www.cor...03f20de7d2.jpg

https://cimg3.ibsrv.net/gimg/www.cor...4ad87dc093.jpg

Great job, thanks for sharing.

I'm having a 92 corvette restored and have been looking for a replacement reservoir only (with no success) when I came across your post. Is yours still working? If so, I'll ask my mechanic to order that piece and try it.

Thanks

Sorry to bring back such an old thread but can you tell me where the other end of that prime pipe connects please?

thank you so very much!

Quote:

Originally Posted by IHBD (Post 1605934697)

The other end is at the ABS pump in the LR cargo bin behind the driver seat. Lift the carpet, remove one screw (7mm head), open the lid, pull out the insulation blanket. There is a bleeder screw above the prime pipe. I connected my Motive bleeder to the master cyl, a hose to the prime pipe bleeder, opened the bleeder and purged/bled the prime pipe. Didn't spill a drop, and the prime pipe had new, fresh fluid in it.

Appreciate the reply. I'm missing the hose at the Mc. So, if I were to connect a new hose at the Mc, where does it connect first so that it goes back to the ABS pump?

Quote:

Originally Posted by IHBD (Post 1605935999)

Only the 92-up has the prime pipe. (The years with Traction Control System).

EXCEPT 96 doesn’t have the prime nipple, even though it has ASR.

Quote:

Originally Posted by IHBD (Post 1605935999)

Only the 92-up has the prime pipe. (The years with Traction Control System).

The prime pipe is a 5mm metal pipe that runs with the other metal brake lines along the bottom of the car just inboard of the LH rocker panel. The forward end of the pipe comes up and runs with the two metal lines that go to the inboard side of the master cylinder. The prime pipe becomes a rubber hose right adjacent to the master cylinder. Look straight down on the inboard side of the master cyl, if you only see two metal lines descending to the frame, there is no prime pipe. If you see three, the larger one is the prime pipe.

Thanks so much for the info. Got a 91 that someone must've put a 92-up MC on so I'll have to figure out what to do with that nipple or get the correct reservoir for it.