39 minutes ago, Zed Head said:

I think that the assumption was that the gas leaking from the damper caused the pressure drop.  That would be a lot of gas though.

The leak was causing gas to puddle underneath the car. 

That's a lot of gas.  Scary.

It didn't start out that way. During the summer there were gas fumes in the garage but no puddle. Any drips would quickly evaporate in the 110 F Phoenix heat. Once it cooled off here I noticed the small puddles. I traced it and you could see the gasoline fizzing out around the dampner adjustment bolt. So I'm sure there was a total loss of pressure between the dampner & engine. 

If is was fizzing out around the adjustment bolt, then the diaphram was ruptured or perished to a point where it started leaking. Would have been interesting to cut it open to see if the rupture was fuel or age related. Could be an early sign of things to come with all these new fuel mixes.

10 minutes ago, EuroDat said:

If is was fizzing out around the adjustment bolt, then the diaphram was ruptured or perished to a point where it started leaking. Would have been interesting to cut it open to see if the rupture was fuel or age related. Could be an early sign of things to come with all these new fuel mixes.

The old dampner was the original one so after almost 40 years its time was up. But I did order a spare Bosch dampner in case it has something to do with the new fuel mixes like you say. On a side note, I had my wheels balanced on a top of the line Hunter Road force balancer today at the Lexus dealership. (They did my 280Z as a favor since we have a LS460) The nasty vibration I was getting above 70 MPH is all gone. I took it up to 95 MPH and it ran straight and silky smooth. Its like a new car! 

I strongly believe in the "road forcing" of the wheels/tires for our Z's. I have to have mine done whenever I get new tires. It costs more but is well worth it.

My damper, both of them, leaked from the exact same place. I think its pretty good it lasted this long though.

 

Update

I bypassed my fuel damper today. Just wrapped a section of injection hose around the top side of it for now. I have put about 50 miles on it and also just let it idle for about 15 minutes and I have no line vibrations or anything else for that matter. I do have the Delphi FD0035 aftermarket fuel pump which has been on there for about 16 years. So far no issues. Unlike Consigli, my line pressure still bleeds off. That'll be next.

Hi all:

Bringing this one back from the dead for an update because I'm going through the back-half of my fuel system; cleaning and de-rusting the tank, new fuel pump, lines and damper.  After searching for OEM unsuccessfully, I ordered this:

https://zcarsource.com/fuel-damper-280z-280zx-75-83-new

But after getting it the other day, I realize it won't work without making a custom mounting bracket.  And I'm concerned about its relatively small size when compared to OEM.  Perhaps it doesn't matter.  But I'd rather find something that mounts like stock.  I've searched repeatedly for the Bosch 0280161024 one referenced in this thread.  But I think they're NLA as well.  I did find one website that listed them, and placed my order last night.  But I halfway expect to get an email from them saying "sorry, out of stock".

https://thmotorsports.com/3304076-bosch-0280161024

We'll see.

EDIT: They cancelled my order.  The part is NLA.

While I'm waiting, how are the "damperless" cars running after a couple of years?  Any issues?

Any other options for the damper?  I've searched using more generic terms, but not found anything in stock that mimics the morphology of the OEM damper.  Thanks in advance.

Edited September 13, 20186 yr by the_tool_man
Updated with order cancellation info.

I don't recall exactly when I removed my leaky damper, maybe 3 years ago? Anyway, no issue's here but then again besides it being an "anti-vibration" device what else is it there for. I don't recall.

 I can see the pointer in my fuel pressure gauge bouncing ever so slightly.

Update:

After much searching, I ordered this one from eEuroParts:



Somewhat disappointingly, it took them a week to ship it, and another four days in transit. But it fits perfectly.  As you can see from the part number stamped on it, it's the same BMW part Consigli found two years ago (280161024).  It just wasn't listed under the same part number.  Maybe that's why they hadn't sold out yet.









Just sharing in case it helps someone else.

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Edited September 24, 20186 yr by the_tool_man
Updated OEM part number

Thanks for doing the research, switched to a new fuel pump on my 77 but pressure drops to zero 1 hr after shutting the engine off. Checked my old pump, cleaned it up and all seems fine. Thinking I will re-install with the damper you found. Cool!


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Can't wait to hear that it worked out. Let us know as soon as you can. I'm thinking of going back to OE fuel pump and damper. So this would be good info.