Brake booster/master cylndr FLANGE(spacer) question

[PATZ]

Hi All! I decided to replace the un-original wrongly sized master cylinder and brake booster from the 240z. I ordered the correct ones from a NON-specialist autoparts supplier. The problem is that there was no flange(the 10mm spacer between the brake booster and master cylinder that nissanman mentioned to me) supplied with the booster. The haynes picture gives me a rough idea what it looks like. I thought it would be as simple as going to the machine shop and having the spacer made with a hole in the middle for the master cylinder to go through till the "ears" with mounting holes contacted the face of the brake booster. But i`m told the flange/spacer has to be made so the m/c seals AIR-TIGHT when it contacts the brake booster. I always thought any such seal/seals to be found in the flange/spacer were to just prevent brake fluid from leaking into the brake booster , and has nothing to do with preserving the right high pressure-low pressure differences within the brake booster housing. Does the fact that the m/c pushrod have to move in and out of the booster necessitate this airtight brake booster and m/c fit? Can anyone possibly show me any pictures(different views) of the flange/spacer and the hole with and without whatever rubber seals are in it? Anyone know where i can order this part in case it isnt just the simple spacer with a hole that i thought i could just have made? I tried the search function but no luck. THANKS! patrick

[Nissanman]

Patrick, I really don't think that the M/C to spacer and spacer to booster surfaces are anything near airtight.

The booster should have a diaphragm in it that has atmosphere on one side, the pedal shaft side, and manifold vacuum on the other side, the M/C side.

There is a seal that goes around the shaft, P/N#1 in the attachment, which seals the vacuum chamber from the atmosphere.

There is no mention of any seal either side of the spacer, so unless anyone else has a different opinion.....

[sblake01]

Graeme, as far as I know, and I've been around these thing for quite a while, your post is 100% correct. Patrick, if you can't find one or don't decide to have one made, I'm pretty sure I have one. I have to look through my stuff which may take a day or so and if it's not here, one on my parts car over in Upland. I don't need it and you can have it for the cost of postage.

[sblake01]

PATZ, this is just a follow up to my previous post. I found a spacer. Now the only problem would be getting it to you over there. PM me if you're interested.

[PATZ]

NISSANMAN- Thanks for all the good info you`ve given me! I got hold of the haynes manual but thanks for posting the illustrations for me anyway! I may take up sblake on his offer.

SBLAKE- i just PM`d you

[Bruce Palmer]

Steve,

FWIW the US Postal folks do a good job for us on overseas shipments.

[sblake01]

Like I said, if he wants it, he's got it. We'll work out the details. Unless time is of the essence, I think the OEM part would be the most foolproof way to go. There's some semi-intricate machining on that part that may or may not make a difference compared to the one a machine shop would make.