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Mysterious vacuum ports on intake BN4

ronzet

Jedi Knight
Offline
Oh gurus of gurus....
I am perplexed. 1958 AH 100-6, BN4.
I have two intake manifolds (BN4 and BJ7) that have two ports, fore and aft, on the intake manifold. I can not figure out what they are for...
Picture 1:
AH intake 1.jpg

AND
AH intake 2.jpg


Can anyone enlighten me???
Thanks,
Ron
 
These ports are on the underside of the manifold. The screw-in fittings are plugged with gunk...

Ron
 
Hi Ron,

This is for the manifold petrol drain pipes. There are small copper pipes, fittings and clips to make up the whole assembly. Check out a Moss catalog in the Manifold section and they will show the Petrol drain assembly. The pipes extend down to just below the oil pan flange (and go through small brackets or clips there). The idea is to allow an out for raw fuel that gets in the manifold during cold starting or when something malfunctions with the carbs. If your carbs are set up properly and you don't over choke they shouldn't need to come into play. Basically, if you see raw fuel under your car something is wrong.

Cheers,
John

Cheers,
John
 
[ QUOTE ]
I have two intake manifolds (BN4 and BJ7) that have two ports, fore and aft, on the intake manifold. I can not figure out what they are for...Can anyone enlighten me???
Thanks, Ron

[/ QUOTE ]

----------------------------

Ron--

When I was in college I had a BN7 to which I fitted a Wolf Whistle which ran off of manifold vacuum--I recall that I drilled and tapped a port on the top and toward the rear end of the manifold. Perhaps some previous owner fitted two of them to your car.

For those not old enough to remember these items--which were required equipment for me and my friends--you can view and/or purchase one for your Healey as well at:

https://www.parts123.com/parts123/yb.dll?parta~showpictxt~Z5Z5Z50000021d~Z5Z5Z522876
 
[ QUOTE ]
For those not old enough to remember these items

[/ QUOTE ]
So what the heck does it sound like.....
Is wolf whistle another name for cat call /ubbthreads/images/graemlins/confused.gif
 
Michael,
I might have agreed with you but for the fact that both the BN4 and the BJ7 manifolds have the same ports.. the chances that two, actually three counting yours, wanted a wolf whistle are, at best, slim... /ubbthreads/images/graemlins/smirk.gif

John, I will check out the manifold overflow on Moss. Thanks one and all..
Ron /ubbthreads/images/graemlins/cheers.gif
 
[ QUOTE ]
So what the heck does it sound like.....

[/ QUOTE ]

wolf whistle

Hey Michael, did these wolf whistles work to attract the intended prey? /ubbthreads/images/graemlins/grin.gif
 
[ QUOTE ]
the chances that two, actually three counting yours, wanted a wolf whistle are, at best, slim

[/ QUOTE ]

Agreed Ron--no way that two other guys could be that cool.
 
[ QUOTE ]
[ QUOTE ]
So what the heck does it sound like.....

[/ QUOTE ]



[/ QUOTE ]

------- /ubbthreads/images/graemlins/savewave.gif

------------------------ Diapason-------------------Keoke- /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/laugh.gif
 
[ QUOTE ]
Diapason

[/ QUOTE ]
Nice word......Had to look that one up. /ubbthreads/images/graemlins/grin.gif

So what does "A full, rich outpouring of harmonious sound". /ubbthreads/images/graemlins/confused.gif sound like?

And do cicks dig it.

Will it make my Elva sound like an Enzo?
 
ronzet,john loftus is correct, my bj7 has the drain lines attached as original,my manifold also has two plugs on the top rear section one is a 3/4" flat hex head plug, the other a square headed 1/4"-3/8" pipe plug, i know this is original but what there used for is beyond me- anyone? johnloftus? --- john did you get my email? /ubbthreads/images/graemlins/savewave.gif
 
Hi Anthony,

The flat hex head plug is for the non-servo models. It gets removed and replaced with a fitting for a hose going to the servo. I think the square pipe plug is for accessory vacuum use .. like Michaels wolf whistle /ubbthreads/images/graemlins/grin.gif Anyway I have a couple BJ7 intake manifolds (non-servo) and they both have the same plugs as yours.

Cheers,
John
 
Gentlemen, Thanks for the words of wisdom... I found the Petrol Drain Pipe on a Moss diagram....once I knew what to look for.

Now, Michael, so that I can be tooooo cooool, where can I get 'one'a dose wolf whistles'? I am sure I can pick up some babes with that!!! /ubbthreads/images/graemlins/smirk.gif
 
[ QUOTE ]
where can I get 'one'a dose wolf whistles'? I am sure I can pick up some babes with that

[/ QUOTE ]

Ron--

Scroll up to my earlier post--there's a link to a site that sells them.
 
On my BJ8 there is also a port with what looks like a 1/4 square nut on it ,its on top of manifold just to rear of the servo pipe. I once saw a similar car which had the crankcase breather tube connected to this apparently it gave a small vacum to the crankcase and rocker box and consequently sucked out all the fumes and also stopped those oil drips. Anyone any ideas if this is a good mod and if so where could I get a suitable connector?
 
Well, now that I have thought about it...

Let's see, I have two float tank overflows and two manifold petrol overflows that, if overflowed, will dump GAS in close proximity to my HOT exhaust header?!?!? Wow, that is a well conceived design..... /ubbthreads/images/graemlins/crazyeyes.gif
 
[ QUOTE ]


So what does "A full, rich outpouring of harmonious sound". /ubbthreads/images/graemlins/confused.gif sound like?

:





[/ QUOTE ]

--- /ubbthreads/images/graemlins/savewave.gif

A Big Healey when he passes you.----Keoke- /ubbthreads/images/graemlins/devilgrin.gif
 
[ QUOTE ]
Anyone any ideas if this is a good mod and if so where could I get a suitable connector?

[/ QUOTE ]

I would think the crankcase breather hose from the valve cover to the rear carb would handle this better. Was this removed on the other car or on yours?
 
No David , to properly vent the crankcase using the manifold vac woluld require the use of a Positive Crankcas Ventillation valve. I have tried a number of them on the big healey and they simply do not work.However, Norm Nock has an article out definng how to do it still did not work for me.---Keoke- /ubbthreads/images/graemlins/hammer.gif
 
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