Master Cylinder Replacement Challenges, Reservoir Lines and Single Pole Contact Options

[DennisV]

I've run into a couple challenges while replacing our brake system.

The new master cylinder has a single pole contact, whereas the original had 2-pole. I read somewhere that you just leave one wire detached. Do you lose some functionality doing that?


I am having a hard time getting the plastic lines that run to the fluid reservoir to naturally land in a position where they would connect. The old lines appear to be identical to each other. Whereas the new lines are different from each other with different part numbers found in the factory parts catalog. Has anyone else run into this? These came from Porsche and I triple checked the numbers on the bag against the catalog. I inserted them into the master cylinder per the indication of the factory parts catalog. I have done all sorts of twisting and contorting but would have to bend one of them substantially to get them to align with the reservoir hoses.


Thank you.

[Superhawk996]

Just a guess

I would think the line with the arrow that has more “reach” (red arrow) would go to the master in the hole that is furthest away from the mounting face of the master and through the slot in the body that is furthest from the reservoir mounting point.

Can’t imagine it will make much difference (IMG:style_emoticons/default/confused24.gif)

Shame Porsche can’t be bothered to make proper parts given how spendy those lines are.

[DennisV]

I would think the line with the arrow that has more “reach” (red arrow) would go to the master in the hole that is furthest away from the mounting face of the master and through the slot in the body that is furthest from the reservoir mounting point.

This logic makes sense, so I gave it a go. Note that this contradicts the placement shown in the factory parts catalog, but it wouldn't be the first time there was an error in the catalog. The shorter metal bend seems to match the footwell contour better. Still not a great fit though. I looked back at some photos I took before disassembly. It appears the line from the master cylinder to the right brake ran forward of the reservoir tubes. So maybe I need to move that.

Up above, the tubes seem too tall where they should mate with the reservoir and are not parallel. The reservoir is not mounted in the photo, but standing a few inches too high. I thought they should follow the floor of that compartment, but they didn't in my before photos either.


This really tried my patience and sucked up much more time that it should have. They seem to have been very deliberate in the bends on these pieces, so I would have expected them to fit the contours of the car much better. Feel like I'm missing something. Maybe my expectations regarding fit and finish are too high for 1970 914.

I may take a heat gun to these and see if I can massage them into a better position.

[Superhawk996]

Maybe my expectations regarding fit and finish are too high for 1970 914.

It’s not a 914 thing. The original lines fit nice.

It’s a Porsche (IMG:style_emoticons/default/sheeplove.gif) thing. They screwed up something - just like they did with the whole CV joint fiasco.

I think 914Sixer may have hit upon it in earlier post - they are probably substituting a 911 line as a 914 part. They already proved how incompetent they were with the CV joints.

I almost wonder if you would be better off comparing the new lines to the old; pick the one that is closest and then order a 2nd one of those. If I’m not mistaken it’s that line with the hard 90 degree bend that doesn’t belong. If you’re lucky maybe argue for a refund of the one that is clearly different. They did refund CV’s to at least 1/2 dozen members here due to that screw up.

I think it might all work out once you do that and move the brake line to the front.

Frustrating though since you’re trying hard to keep it original as a /6.

EDIT: if you would be so kind, please post for others which part number is the one that matches the original line