Hello! Log in or Register   |  Help  |  Donate  |  Buy Shirts  See all banner ads | Advertise on TheSamba.com  
TheSamba.com
 
EFI air bleed?
Forum Index -> Performance/Engines/Transmissions Share: Facebook Twitter
Reply to topic
Print View
Quick sort: Show newest posts on top | Show oldest posts on top View previous topic :: View next topic  
Author Message
TinCanFab
Samba Member


Joined: April 04, 2006
Posts: 2546
Location: Waterford, California
TinCanFab is offline 

PostPosted: Wed Nov 25, 2015 10:46 am    Post subject: EFI air bleed? Reply with quote

Hey guys, I've got a question about my EFI setup. Do I need, or should I incorporate a way to bleed the air out of the lines? I'm familiar with fučl injection, but I've never installed a system that I've made from scratch. I'm getting fuel pressure, no leaks but a ton of gurgling and squeeking noises coming from only the regulator. I changed the spin on filter and allowed the tank to drain out of it all the way to the pump inlet. Then I connected to the pump. Do I just run the engine until air goes away?


Image may have been reduced in size. Click image to view fullscreen.


The regulator is the highest point in the system, but sounds like a whoopie cushion every 10 seconds or so.

Image may have been reduced in size. Click image to view fullscreen.


I have the return line routed back to the fuel inlet instead of dumping into the top of the tank.

Image may have been reduced in size. Click image to view fullscreen.


The gauge bounces around when I hear the gurgling but mostly stays around 40 psi.
_________________
Check out my truck brought back from the dead... http://www.thesamba.com/vw/forum/viewtopic.php?t=420762&highlight=sprayed+blood

They're never really ever finished 58 rag build...
http://www.thesamba.com/vw/forum/viewtopic.php?t=658092
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
mikedjames
Samba Member


Joined: July 02, 2012
Posts: 1356
Location: Hamble, Hampshire, UK
mikedjames is offline 

PostPosted: Wed Nov 25, 2015 11:22 am    Post subject: Re: EFI air bleed? Reply with quote

"I have the return line routed back to the fuel inlet instead of dumping into the top of the tank. "


So the air just runs around.

Look at swirl pots and running a low pressure loop throuh the pot
or simply dup the hot aerated fuel back into the tank.
Otherwise your burps and squeaks may end up with boiled fuel instead and no FI until it all cools down.

The choice of how to return fuel to the tank is one thing stalling my FI project.
_________________
Ancient vehicles and vessels

1974 VW T2 : Devon Eurovette camper with 1641 DP T1 engine, Progressive carb, full flow oil cooler
Engine 1: 40k miles (rocker shaft clip fell off), Engine 2: 30k miles (rebuild, dropped valve). Engine 3: a JK Preservation Parts "new" engine: 16k miles to date.

1979 Westerly GK24 24 foot racer/cruiser yacht Forethought of Gosport.
1973 wooden Pacer sailing dinghy
Back to top
View user's profile Send private message Visit poster's website Gallery Classifieds Feedback
fastfil
Samba Member


Joined: November 25, 2006
Posts: 351
Location: Sunshine Coast, AUS
fastfil is offline 

PostPosted: Wed Nov 25, 2015 11:58 am    Post subject: Re: EFI air bleed? Reply with quote

The injectors should run a priming pulse when you turn the ignition on. This should purge any small amounts of air out. If its a new motor, you might just need to turn it off and on a few times.
_________________
"...swingaxle...transaxle...same diff."
Back to top
View user's profile Send private message Gallery Classifieds Feedback
TinCanFab
Samba Member


Joined: April 04, 2006
Posts: 2546
Location: Waterford, California
TinCanFab is offline 

PostPosted: Wed Nov 25, 2015 12:26 pm    Post subject: Re: EFI air bleed? Reply with quote

fastfil wrote:
The injectors should run a priming pulse when you turn the ignition on. This should purge any small amounts of air out. If its a new motor, you might just need to turn it off and on a few times.


Yes, new everything. I don't have an ECU to connect to the injectors yet. I've just been putting power to the pump in short cycles so far.
_________________
Check out my truck brought back from the dead... http://www.thesamba.com/vw/forum/viewtopic.php?t=420762&highlight=sprayed+blood

They're never really ever finished 58 rag build...
http://www.thesamba.com/vw/forum/viewtopic.php?t=658092
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 12:32 pm    Post subject: Re: EFI air bleed? Reply with quote

mikedjames wrote:
"I have the return line routed back to the fuel inlet instead of dumping into the top of the tank. "


So the air just runs around.
This.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 12:50 pm    Post subject: Re: EFI air bleed? Reply with quote

i ran it like you did. no problems. it will go away once you purge out the air the first time.nothing wrong with running a tee instead of returning to tank.
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 1:24 pm    Post subject: Re: EFI air bleed? Reply with quote

There is a reason all manufacturers run an extra hose back to the tank.
I will likely work most of the time anyway, but not well enough to sell new cars.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
mcmscott
Samba Member


Joined: March 12, 2010
Posts: 4409
Location: sanger ca
mcmscott is offline 

PostPosted: Wed Nov 25, 2015 1:46 pm    Post subject: Re: EFI air bleed? Reply with quote

I had a system like that, burned up 2 pumps. There is a reason factory efi systems return in the top of the tank
_________________
There are no stupid questions, only stupid people,

68 Ghia
67 T-1
65 Notch
02 Mexican beetle
74 Thing
15 Long travel rail
07 Nomad
05 f-250
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 1:46 pm    Post subject: Re: EFI air bleed? Reply with quote

and there are also new cars that dont return at all. i guess they are wrong too. alot of people including myself have run it this way without problems. if it idles ok than it should be fine becouse thats when you get the most return. the more rpm the less return.
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 1:56 pm    Post subject: Re: EFI air bleed? Reply with quote

So, some undiscosed manufacturer runs without return. This is interesting, I would like to know more about this.
The rest of us should clearly do it as well, because those who burned pumps and suffered from hard starting with warm engines simply dont know what they are doing.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 2:05 pm    Post subject: Re: EFI air bleed? Reply with quote

You're probably familiar with "return-type" fuel injection systems, but have you worked on a "returnless" system?

Returnless systems are found on many late model cars and trucks. The first ones appeared back in 1993 on certain Chrysler V6 and V8 truck engines. By 1998, all Chrysler cars and light trucks had them. In 1996, Toyota introduced its first returnless system, followed by General Motors and Ford in 1999. Honda went "returnless" in 2001, and today you'll find returnless fuel injection systems on almost all new vehicles.


http://www.aa1car.com/library/returnless_efi.htm
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 2:21 pm    Post subject: Re: EFI air bleed? Reply with quote

I read through the link you provided. Interesting stuff. But as expected, those systems serve the purpose to solve a problem few of us are concerned about - namely emission control.
In order to make this work they have to raise fuel pressure to avoid vapor buildup in the lines.
I have never worked on newer tech like this, and still fail to see any relevance to us.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 2:26 pm    Post subject: Re: EFI air bleed? Reply with quote

So you just want to argue. well my dad can kick your dads ass!!!
next up religion!! Razz
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 2:36 pm    Post subject: Re: EFI air bleed? Reply with quote

No, advocating returnless fuel injection with older tech pumps and regulators is bad advice. The fact that more modern systems use this with completely different hardware is no reason for us to do it.
Experimenting should be encouraged, but this forum supply advice to people who need help on their builds.
Saying that a return is not necessary without also saying that you need a special pump/regulator/software is not nice.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 2:40 pm    Post subject: Re: EFI air bleed? Reply with quote

ok ok you caught me i was advocating returneless fuel injection. dang nothing gets by you.
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 2:41 pm    Post subject: Re: EFI air bleed? Reply with quote

before you reply. you win! everything you say should be followed to a tee...
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Boolean
Samba Member


Joined: January 19, 2012
Posts: 1712
Location: Stockholm
Boolean is offline 

PostPosted: Wed Nov 25, 2015 2:48 pm    Post subject: Re: EFI air bleed? Reply with quote

Very clever conclusion. It has nothing to do with the discussion, but hey - we can't have everything.
_________________
I strive for perfection. Excellence will not be tolerated!
Build thread here:
http://www.thesamba.com/vw/forum/viewtopic.php?t=529379
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gprudenciop
Samba Member


Joined: July 06, 2008
Posts: 579
Location: portland or
gprudenciop is offline 

PostPosted: Wed Nov 25, 2015 3:14 pm    Post subject: Re: EFI air bleed? Reply with quote

there is more than one way to skin a cat. why you would want to skin a cat is beyond me! i prefer woking the dog..... Laughing
_________________
Never look down at anybody unless you are helping them up..
Loaning someone your strength instead of reminding them of their weakness = kindness..
Back to top
View user's profile Send private message Gallery Classifieds Feedback
TinCanFab
Samba Member


Joined: April 04, 2006
Posts: 2546
Location: Waterford, California
TinCanFab is offline 

PostPosted: Wed Nov 25, 2015 4:12 pm    Post subject: Re: EFI air bleed? Reply with quote

Hey now.... Smile

I tried to research the pros/cons of the different returns before I set it up. The main reason I did it this way was the single cab tank placement. It was also easier to plumb into the existing tank drain. I'm using a fuel cell with no baffling so it seemed this method would keep air out of the drain while fuel sloshes around.

I've read that some guys feel the return in the top of the tank aerates the fuel? I tried to keep the lines away from heat and even made the rails out of steel to lessen the impact of heat soak. You can see I even used a Y fitting instead of a regular tee since some guys said the CB system's tee was no good... Hmmmmm...I went overkill on the tubing and hose sizes and used AN to keep flow restriction to a minimum. The pump volume is also ridiculous for my hp level, but that's how I roll. Overkilling the hell out of everything I build lately. Wink carry on
_________________
Check out my truck brought back from the dead... http://www.thesamba.com/vw/forum/viewtopic.php?t=420762&highlight=sprayed+blood

They're never really ever finished 58 rag build...
http://www.thesamba.com/vw/forum/viewtopic.php?t=658092
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
clonebug
Samba Member


Joined: January 29, 2005
Posts: 3217
Location: NW Washington
clonebug is offline 

PostPosted: Wed Nov 25, 2015 10:46 pm    Post subject: Re: EFI air bleed? Reply with quote

I have almost 12,000 miles on my FI turbo with a fuel tank tee.

I have not had any issue with fuel.......except I am now at 94% duty cycle on my 32# injectors at 22 lbs boost........ Crying or Very sad Crying or Very sad

Image may have been reduced in size. Click image to view fullscreen.

_________________
vwracerdave wrote:

Take a good long look in the mirror and report back on what you see.


Paul.H wrote:
That one line on that chart is probably better info than you can get from this place in a month



My Megasquirt Fuel Injection Turbo Buggy Build
(Now with Water/Alcohol Injection)
Upgraded to MS-2 Extra direct fire wasted spark

http://www.shoptalkforums.com/viewtopic.php?f=3&t=127936
Back to top
View user's profile Send private message Send e-mail Classifieds Feedback
Display posts from previous:   
Reply to topic    Forum Index -> Performance/Engines/Transmissions All times are Mountain Standard Time/Pacific Daylight Savings Time
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

About | Help! | Advertise | Donate | Premium Membership | Privacy/Terms of Use | Contact Us | Site Map
Copyright © 1996-2020, Everett Barnes. All Rights Reserved.
Not affiliated with or sponsored by Volkswagen of America | Forum powered by phpBB