Vapor lock questions for the hotter climate guys

[Stanley]

Won't help though if it happens sitting in traffic.

[jalexquijano]

On ‎12‎/‎16‎/‎2016 at 7:10 PM, siteunseen said:

And a Merry Christmas to us all!  

Please replace the fuel rail with rubber fuel hose.  it's proven to help with percolation of fuel, as per Jeff G an automotive engineer with a race team that uses the 240Z.

Jeff G,

Any picture of your engine bay? I would like to see how you routed the rubber fuel hose far or behind the valve cover....

[Jeff G 78]

My Z is in a friends garage, so I don't have anything handy.  I do plan to go over and work on it this weekend though, so I will try to get some pics.  Keep in mind, my car is a race car and function was far more important than looks when I routed the lines.  For a street car, I would have done things differently.

[jalexquijano]

I dont ming! Just want to know how was the routing done and which type and size of hose did you use.

 

 

[jalexquijano]

On ‎10‎/‎05‎/‎2016 at 3:33 PM, Zed Head said:

Sounds more like percolation, I think.  Basically, fuel getting too hot in the carbs and forcing/finding its way out unmetered, adding extra fuel, I believe.  Still heat-related, so the rubber lines Jeff G described should help.  Progress!

It's been discussed before, part of the saga.  Might even be in previous pages of this thread.  Here's Nissan's take on it. - http://xenonzcar.com/s30/files/1973 240z 1974 260z fuel system modifications.pdf

That document is on the CZCC site also - 

 

This is correct. What i am getting is fuel percolation at both carbs. I even replaced the fuel rail with rubber hoses this weekend and was still getting rough idle under a heavy traffic at 11:00 a.m. bumper to bumper. Car started to hesitate and stalled a couple of times. However i did found this company called THERMO-TEC which provides solutions to wrap the fuel lines and wrap the heat shield extensions:

http://thermotec.shptron.com/c/heat-protection?pp=8&pg=2

Which of all the products they sell can work to wrap the fuel rail and cover the heat shield extensions?

 

 

[psdenno]

This has been an ongoing problem for a long time and I don't remember all of the remedies you've tried other than fuel pump and fuel lines, so excuse me if you've already tried what follows. 

Have you tried letting the Z idle in a shaded spot with the hood open all the way and an external fan blowing down on the carbs to push  heat build up away and then revving the engine when it gets to operating temperature to see if it stumbles?  That could confirm or eliminate the fuel percolation aspect.  Have you connected with any of the Nissan clubs in Panama?

Dennis

 

 

[jalexquijano]

On ‎05‎/‎03‎/‎2017 at 5:28 PM, psdenno said:

This has been an ongoing problem for a long time and I don't remember all of the remedies you've tried other than fuel pump and fuel lines, so excuse me if you've already tried what follows. 

Have you tried letting the Z idle in a shaded spot with the hood open all the way and an external fan blowing down on the carbs to push  heat build up away and then revving the engine when it gets to operating temperature to see if it stumbles?  That could confirm or eliminate the fuel percolation aspect.  Have you connected with any of the Nissan clubs in Panama?

Dennis

 

 

I think the 280zx injector cooling blower is the remedy. Anyone differs?

[Mark Maras]

 Try the fan. You've got nothing to lose except the problem. BTW, If adding choke improves the performance, The engine is running too lean AT THAT POINT IN TIME.

[psdenno]

On 5/3/2017 at 3:28 PM, psdenno said:

This has been an ongoing problem for a long time and I don't remember all of the remedies you've tried other than fuel pump and fuel lines, so excuse me if you've already tried what follows. 

Have you tried letting the Z idle in a shaded spot with the hood open all the way and an external fan blowing down on the carbs to push  heat build up away and then revving the engine when it gets to operating temperature to see if it stumbles?  That could confirm or eliminate the fuel percolation aspect.  Have you connected with any of the Nissan clubs in Panama?

Dennis

 

 

I think the 280zx injector cooling blower is the remedy. Anyone differs?

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Perhaps it's a language problem.  I asked a couple questions about troubleshooting and your ability to connect with other Nissan owners in Panama.  In your response, you quoted my questions and then answered with a question about an injector cooling blower.  WTF! (Spanish translation available upon request). Ya no puedo ayudarte.

Dennis

 

 

[jalexquijano]

No language problem! I just want your confirmation that asides from the wrapping of the stainless Steel heat shield extensions, the 280zx air injector manifold cooling blower shown could solve the percolation. As simple as that. And by the way, no nissan club in Panama!

[Zed Head]

The blower might help.  Odd that the nozzles appear to point directly at each carb.  Could be that they designed it for carbs, then switched to EFI, then finally broke it out for the ZX's.  Wouldn't be surprised if they had all of the tooling ready to go for carbs but avoided implementing it.

[Mark Maras]

10 minutes ago, Zed Head said:

The blower might help.  Odd that the nozzles appear to point directly at each carb.  Could be that they designed it for carbs, then switched to EFI, then finally broke it out for the ZX's.  Wouldn't be surprised if they had all of the tooling ready to go for carbs but avoided implementing it.

 I didn't notice that. It does look "made to order" for twin hitachi's.