I think you should go ahead and plug that off but a better way to test it would be hold that tube on first start up of the day. If it gets hot quickly then you have coolant running through there for sure.  But if you drive it for awhile and it feels hot that would be the exhaust manifold heating it up. I drove mine an hour or so Saturday and grabbed that tube and it was hot as hell. It's right above my header. I'll show you a quick and easy way of testing it tomorrow,  I'm using my phone now and away from my laptop.

A simple way to accomplish the objective would be to find a ball bearing or short stud that will fit inside the short section of rubber hose, but not in to the metal nipples the hose attaches to.  Remove one end of the hose, insert the plug, reattach the hose.  The flow is blocked and the original sealing surfaces are maintained for no leakage.

pictures please!! need to see pictures before doing the surgery!!

It's minor surgery!!!! Go ahead and try it....

Site, you don't really have to plug the carb intake holes, you could leave them open with no problems, makes the job 50% easier.

Post #208, first picture.  Loosen hose clamps (turn screw counterclockwise), pry off hose, stick something in hole, put hose back on, tighten hose clamps (turn screw clockwise).

I was going to also suggest Vise Grips if there is a longer section of hose that you can clamp.  As a test.

http://www.irwin.com/tools/locking-tools/the-original-long-nose-locking-pliers-with-wire-cutter

13 hours ago, grannyknot said:

Site, you don't really have to plug the carb intake holes, you could leave them open with no problems, makes the job 50% easier.

I plugged mine to keep bugs out and it looks a little better than an open hole.  But the Vapor Lock man can make that decision, it would be easier especially for testing.

13 hours ago, Zed Head said:

Post #208, first picture.  Loosen hose clamps (turn screw counterclockwise), pry off hose, stick something in hole, put hose back on, tighten hose clamps (turn screw clockwise).

I was going to also suggest Vise Grips if there is a longer section of hose that you can clamp.  As a test.

http://www.irwin.com/tools/locking-tools/the-original-long-nose-locking-pliers-with-wire-cutter

Yes!  Just plug the thermostat housing and the hose coming off the hardline at the rear for a quick test.  If it helps with your problem then go back and make it look good.

Like I showed in post #202,  

 

Pull these hoses off and stick a bolt inside them and retighten the clamp for a temporary test.  Drive the car and see if it helps, won't cost you a dime and you should be able to do it in ten minutes.  Then take the metal fuel rail off and replace with rubber fuel line like Jeff G said a month or two ago.

This is your motor so there shouldn't be any confusion.

Front hose coming off thermostat housing,

Rear hose coming off the hardline that runs behind the head,

 

Edited December 15, 20168 yr by siteunseen

14 hours ago, jalexquijano said:

pictures please!! need to see pictures before doing the surgery!!

Sounds like some doctors I use!  

 

On ‎12‎/‎01‎/‎2016 at 1:18 PM, siteunseen said:

Yes.  I would do both if it were mine and I was having problems with percolation.  Take one of the old fittings to the parts supply and match it up.  I used brass NPT 1/8 I think but don't really remember, take the old ones for comparison.  

EDIT: Looking back I see I used the old threaded plugs off the balance tube but you can get brass plugs at any hardware store.

I started on the passenger's side, that hose pulls from the rear intake.  Plugging it at the water pump eliminates the metal tube running behind the head to the rear intake, threaded plug goes into the intake.  Picture #2

Then plug the front intake,

Then plug the thermostat housing,

 

 

 

Okay! Im doing this on Friday! i am blocking it with brass plugs. Hope this keeps the heat out of those carbs and eliminates the rpm oscilations at idle and tendency to stall during traffics and traffic lights.

2 hours ago, jalexquijano said:

Okay! Im doing this on Friday! i am blocking it with brass plugs. Hope this keeps the heat out of those carbs and eliminates the rpm oscilations at idle and tendency to stall during traffics and traffic lights.

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.

Merry Christmas to all of you!!! Picking up the car today from the mechanic!! Hope the plugging helps!! If not i will need to eliminate the fuel rail. Its a shame as i wanted to keep the car stock!!