Moparts

Bogus fuel vapour separator

Posted By: RealWing

Bogus fuel vapour separator - 06/19/12 01:00 AM

Have had great difficulty getting my 440-6bbl Superbird fired up. Could not get fuel to the carbs. After installing another new fuel pump, finally found that by pinching off the return line from the vapour separator cannister, I got lots of fuel to the carbs. After some searches of A12 forums, I saw reference to bogus separators. I had purchased mine several years ago thru YearOne.
I cut it open and it is complete junk!!

There is no filter screen at all, there are only short stubs on the 3 lines and no orifice in the return line at all!! All my fuel was going straight back to the tank!!

Mumble, mumble

Attached picture 7255403-IMG_8181.JPG
Posted By: RealWing

Re: Bogus fuel vapour separator - 06/19/12 01:02 AM

The other end

Attached picture 7255408-IMG_8182.JPG
Posted By: RealWing

Re: Bogus fuel vapour separator - 06/19/12 01:04 AM

This is what it should look like inside

Attached picture 7255410-Vapourseparatorc.jpg
Posted By: 71birdJ68

Re: Bogus fuel vapour separator - 06/19/12 01:37 AM

Did you call them, and what did they say?
Posted By: sunroof446

Re: Bogus fuel vapour separator - 06/19/12 02:23 AM

The repros are junk. Real ones have a .060 hole on the return. The repros return fuel to fast to the tank. I cut a real one open. There is a brass screen inside. You can soak them in cleaner. Blow them out & reuse them.
Posted By: moparfan53

Re: Bogus fuel vapour separator - 06/19/12 03:10 AM

The thread below has some info about how to get the correct orifice size, how different return orifice sizes affect fuel pressure and which suppliers have ones with the orifice. It also mentions the correct ones may possibly be identified by having INLET OUTLET stamped on the can.

RealWing, is your's stamped that way?

https://board.moparts.org/ubbthreads/show...;gonew=1#UNREAD
Posted By: RealWing

Re: Bogus fuel vapour separator - 06/22/12 03:01 AM

Quote:

The thread below has some info about how to get the correct orifice size, how different return orifice sizes affect fuel pressure and which suppliers have ones with the orifice. It also mentions the correct ones may possibly be identified by having INLET OUTLET stamped on the can.

RealWing, is your's stamped that way?

There were no stampings on mine at all. Thanks for the link to orifice sizing. I'll be reducing the size of the orifice on a replacement down to approx .035".

https://board.moparts.org/ubbthreads/show...;gonew=1#UNREAD

Posted By: RealWing

Re: Bogus fuel vapour separator - 06/22/12 10:28 PM

I got a new one from Bill at A+M HighTech Auto. It has in and out stampings. The return line does not have an actual "orifice" in it. It is simply restricted by the size of the outlet nipple. The nipple ID was ~0.115" - which is a lot more area than the factory specified 0.060" (almost 4 times as big an area). I soldered the end closed and drilled a 0.040" hole.

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Posted By: RealWing

Re: Bogus fuel vapour separator - 06/22/12 10:29 PM

This is the other end and shows the soldered return line and the 0.040" hole.

Attached picture 7261161-IMG_8209.JPG
Posted By: 68jim

Re: Bogus fuel vapour separator - 06/23/12 12:15 AM

I soldered my return line as well when I discovered that the .090-.100 hole that was there would drop my fuel pressure at idle by 2 psi. I went slightly smaller around .031 and that only dropped the pressure by .5 psi, so I still have the same function of sending any air/vapors and some fuel back to the tank. I plumbed in a small fuel pressure gauge at the fuel line Tee (running 2 AFBs) so I could see what was going on. I've since corrected my other fuel problems (Carter mech fuel pump leaking check valves, clamp on line not tight and sucking some air when engine warmed up, return orifice too big) but I left the gauge in place. I've since noticed that when I shut off the motor, my pressure will soon drop to zero as the return line dumps any pressure back to the tank. My AFBs have a vent valve on the top of the carb and once the fuel/ethanol evaporates a small amount the float will drop and the line from the carbs drains down empty to the vapor separator. This is not really a problem for my set up since I run a small Carter electric pump in the back by the tank with a check valve in parallel. I run the electric for about 20 seconds to prime and pressurize the fuel lines then shut it off, and the hemi fires up quickly every time, even with points...
This may not be the best for every situation but it works for me. I even took it out in 100+ degree temps last Summer to see how it would act - all happy.

Jim
Posted By: moparfan53

Re: Bogus fuel vapour separator - 06/23/12 02:08 AM

Thanks RealWing and 68jim for the pics and info.
Posted By: biginchmotor

Re: Bogus fuel vapour separator - 06/23/12 02:20 AM

Thanks for taking the time to post this, buddy of mine bought one of these from Year One about the same time. His car is running good but we will be cutting his to see if there is a screen in there also. Great info here, John.
Posted By: 68jim

Re: Bogus fuel vapour separator - 06/23/12 02:18 PM

When I became aware of the lesser quality seperators on the market I checked the ones I had to see if they were the good ones or not. I can't think of a way to verify the screen but I did verify that the inside tubes were the correct length by using a small piece if wire (coat hanger maybe) with just a slight bend or partial hook at the end. As I slid it down the tube I could feel where the tube ended then marked the wire. Holding the wire on the ouside of the can gave me confirmation that at least the tubes where the correct length.

Jim
Posted By: hemi71x

Re: Bogus fuel vapour separator - 06/23/12 10:02 PM

Not to hijack this posting, but i purchased this fuel vapor seperator this morning at a local car show.
It's a NOS piece and the part number appears to be 3577867
Purchased back in 10-21-82
Can anyone tell me which year it's officially for?
I have been hearing that the mounting bracket is different between years, but i haven't a clue as to what the difference is.

Attached picture 7262366-FuelVaporSeparator003(Small).JPG
Posted By: Firepowerflyer

Re: Bogus fuel vapour separator - 06/23/12 10:56 PM

I have to crank my 69 GTX over forever for it to get fuel.Once it's started it seems fine,I don't have any miles on it yet,but if it sit's in the garage a day or two it's the same deal.Whats going on is the fuel draining back to the tank?Shouldn'nt there be some left in the carb float area?I bought the seperator from A&M and had my carb done at Harms,it seems to run great other than the hard start up but. I've been meaning to ask on here what was going on with this thing.
Posted By: 1MYTGTX

Re: Bogus fuel vapour separator - 06/24/12 12:51 AM

Quote:

I have to crank my 69 GTX over forever for it to get fuel.Once it's started it seems fine,I don't have any miles on it yet,but if it sit's in the garage a day or two it's the same deal.Whats going on is the fuel draining back to the tank?Shouldn'nt there be some left in the carb float area?I bought the seperator from A&M and had my carb done at Harms,it seems to run great other than the hard start up but. I've been meaning to ask on here what was going on with this thing.



Went through that same BS with my restored AVS....I fixed it by swapping my Holley back on!
Posted By: hemi71x

Re: Bogus fuel vapour separator - 06/24/12 12:59 AM

https://board.moparts.org/ubbthreads/show...e=1#Post7252958

Guys, read this posting over in the Q&A section about fuel problems, hard starting, long cranking, problems.
Posted By: Firepowerflyer

Re: Bogus fuel vapour separator - 06/24/12 02:06 AM

Quote:

Quote:

I have to crank my 69 GTX over forever for it to get fuel.Once it's started it seems fine,I don't have any miles on it yet,but if it sit's in the garage a day or two it's the same deal.Whats going on is the fuel draining back to the tank?Shouldn'nt there be some left in the carb float area?I bought the seperator from A&M and had my carb done at Harms,it seems to run great other than the hard start up but. I've been meaning to ask on here what was going on with this thing.



Went through that same BS with my restored AVS....I fixed it by swapping my Holley back on!



I can't beleive theres not a way to fix it.I like my holleys but the avs are good carbs.
Posted By: gtx6970

Re: Bogus fuel vapour separator - 06/24/12 04:39 PM

Quote:


Can anyone tell me which year it's officially for?




1972 only
Posted By: Snoopy

Re: Bogus fuel vapor separator - 06/24/12 05:51 PM

Quote:

I had purchased mine several years ago thru Year One.




Contact Year One about the problem. I bet they will rectify the problem. They are one of the best companies around when it comes to backing what they sell.
Posted By: Anonymous

Re: Bogus fuel vapor separator - 06/24/12 06:35 PM

Quote:

Quote:

I had purchased mine several years ago thru Year One.




Contact Year One about the problem. I bet they will rectify the problem. They are one of the best companies around when it comes to backing what they sell.



Posted By: JohnRR

Re: Bogus fuel vapour separator - 06/25/12 01:27 AM

Quote:

Quote:

Quote:

I have to crank my 69 GTX over forever for it to get fuel.Once it's started it seems fine,I don't have any miles on it yet,but if it sit's in the garage a day or two it's the same deal.Whats going on is the fuel draining back to the tank?Shouldn'nt there be some left in the carb float area?I bought the seperator from A&M and had my carb done at Harms,it seems to run great other than the hard start up but. I've been meaning to ask on here what was going on with this thing.



Went through that same BS with my restored AVS....I fixed it by swapping my Holley back on!



I can't beleive theres not a way to fix it.I like my holleys but the avs are good carbs.



Tthere is , install an electric fuel pump and fill the carb before starting.

The fuel today is formulated to work with FUEL INJECTION, the carburetor hasn't been OEM for over 20 years ...
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