Author Topic: Puzzle on return line  (Read 4908 times)

April 20, 2011, 03:42:30 pm

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Puzzle on return line
« on: April 20, 2011, 03:42:30 pm »
It`s NA and I suspect of small air leak on return line,so I put clear line on both.Line to tank is full of fuel(and for now it`s all about line from IP to Injector),but to injector NON of fuel, if i put same by hand pump it go to half and stop.Than I close line from IP, and put another line from injector to bottle to see only just drops aftar 30 min,even on high rpm,by the way motor ran OK.
I have little banjo on return from injectors so I lose one and than I blow it has flow so not blocked.Is it possible that there is no flow from injector to IP,and why they put on it anyway(I suspect about it)

ps. I see no presure on aditional line from injectors to bottle,puzzle man aka Quantum-man man as I remmember said that there is no return flow from 193,293 etc.nozzles-injector, and that is because construction of injectors themselvs.Puting 3 bar on every line and it hold.I change fuel filter because I think it created same vacum and air in return line,so I have more cranking,but what about flow you think?
pss.I thinking about blocking that line forever.


I`ll improve my English

Reply #1April 20, 2011, 04:20:35 pm

R.O.R-2.0

  • Veteran

  • Offline
  • ***

  • 7335
  • Personal Text
    Pacific Northwest - Oregon - USA
Re: Puzzle on return line
« Reply #1 on: April 20, 2011, 04:20:35 pm »
the over flow from the injectors doesnt even flow fuel unless your right around wide open throttle, if i understand things correctly..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #2April 20, 2011, 04:20:53 pm

745 turbogreasel

  • Guest
Re: Puzzle on return line
« Reply #2 on: April 20, 2011, 04:20:53 pm »
Worn injectors have more leakby.

Blocking the return will stall the engine or blow off a line.

Air in the return- so what? You are done with that fuel anyway.
sucking air at pump input shaft- that might give the impression of air entering at the return, but be a problem.

I may not have read your question correctly, hope this helps.

Reply #3April 20, 2011, 04:22:53 pm

745 turbogreasel

  • Guest
Re: Puzzle on return line
« Reply #3 on: April 20, 2011, 04:22:53 pm »
Worn injectors have more leakby.  Flow from the injectors is just a trickle when all is well.

Blocking the return will stall the engine or blow off a line.

Air in the return- so what? You are done with that fuel anyway.
sucking air at pump input shaft- that might give the impression of air entering at the return, but be a problem.

I may not have read your question correctly, hope this helps.

Reply #4April 20, 2011, 05:20:42 pm

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Re: Puzzle on return line
« Reply #4 on: April 20, 2011, 05:20:42 pm »
Thanks for responding

R.O.R-2.0
Man I try couple times wide open throttle in my 30 min test and noting

745 turbogreasel
So if i don`t have injectors leakby - than no flow to ip - than I am OK,but samehow not like to be normal for me(no fuel in that line).
 I Block the return FROM INJECTORS TO IP ONLY and what not stall the engine or blow off a line,by the time I try for shure.I didn`t block return to tank of corse.
I got air on seating same how,in a drive it`s OK.
Best
I`ll improve my English

Reply #5April 20, 2011, 05:37:10 pm

theman53

  • Global Moderator
  • Veteran

  • Offline
  • ****

  • 7834
  • Personal Text
    Holmes County Ohio - North Central Ohio
Re: Puzzle on return line
« Reply #5 on: April 20, 2011, 05:37:10 pm »
I would think at idle would be when you would have the most fuel unused and returning to the tank.

Hook the lines up just as they were and you won't have any problems with that side. If you are getting air then you probably have something before that giving you trouble...from the filter to the IP most likely.

Reply #6April 20, 2011, 10:34:57 pm

rabbitman

  • Veteran

  • Offline
  • ***

  • 2787
Re: Puzzle on return line
« Reply #6 on: April 20, 2011, 10:34:57 pm »
the over flow from the injectors doesnt even flow fuel unless your right around wide open throttle, if i understand things correctly..

I have clear lines on the injector barbs and I can see them flowing at idle. I haven't revved it to compare though.
'82 Rabbit, I put on a euro vnt-15, 2.25" DP, 2.5" exhaust, the result.....it whistled.

I removed the turbo, made a toilet bowl 2.5" DP, the result....it was deafening. Now it has a homemade muffler up front and a thrush in the rear, the result.....less loud.
Watch: AGENDA, GRINDING AMERICA DOWN

Reply #7April 21, 2011, 03:55:16 am

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Re: Puzzle on return line
« Reply #7 on: April 21, 2011, 03:55:16 am »
Air and return to tank isn`t problem.
Problem is RETURN TO IP from injectors,as I see this pump can (and must) deliver up to 3 times more fuel than one need,so look like I have same magic there,and I

drive it w/o problem on high rpm so I have enough fuel.

I think long time ago,when I put clear lines I have fuel in both return lines or not ?
In a few years on forum I never heard anything like this,so help me to have fuel instend of air in that line.
ps.injectors are tested 2k before.
I`ll improve my English

Reply #8April 21, 2011, 07:27:55 am

theman53

  • Global Moderator
  • Veteran

  • Offline
  • ****

  • 7834
  • Personal Text
    Holmes County Ohio - North Central Ohio
Re: Puzzle on return line
« Reply #8 on: April 21, 2011, 07:27:55 am »
I don't see any problem. I would think this to be normal. I must not understand, what is the problem with little to no fuel going back to the pump from the injectors?

Reply #9April 21, 2011, 12:32:20 pm

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Re: Puzzle on return line
« Reply #9 on: April 21, 2011, 12:32:20 pm »
Problem is because line is not only empty there is air,that air is sucked by seating overnight.So that I was pump before up to 1/2 line is gone.
Yea,I know you will say chek air leak,but puting 3 bar on every line and it hold,and no flow at all,before clear line I`ll bet that`s full. t
Does anybody have empty line from injectors to IP like me?Best
I`ll improve my English

Reply #10April 21, 2011, 12:39:28 pm

R.O.R-2.0

  • Veteran

  • Offline
  • ***

  • 7335
  • Personal Text
    Pacific Northwest - Oregon - USA
Re: Puzzle on return line
« Reply #10 on: April 21, 2011, 12:39:28 pm »
Problem is because line is not only empty there is air,that air is sucked by seating overnight.So that I was pump before up to 1/2 line is gone.
Yea,I know you will say chek air leak,but puting 3 bar on every line and it hold,and no flow at all,before clear line I`ll bet that`s full. t
Does anybody have empty line from injectors to IP like me?Best

pressure may not make the line leak. may need to apply suction to find a leak..
92 Jetta GLI - Black, 1.6D w/ GT2056V turbo..
86 GTI - 4 Door, Med Twilight Gray, Tow Machine..
86 Audi Coupe GT - Tornado Red, All Stock.. WRECKED.
89 Toyota 4Runner - Dark Grey Metallic, LIFTED!

Turbo: exhaust gasses go into the turbocharger and spin it, witchcraft happens and you go faster.

Reply #11April 21, 2011, 04:27:58 pm

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Re: Puzzle on return line
« Reply #11 on: April 21, 2011, 04:27:58 pm »
pressure may not make the line leak. may need to apply suction to find a leak..

Thx,but I have only compressor.
Q is for this pazzle:Does anybody have empty line from injectors to IP like me?Best
I`ll improve my English

Reply #12April 21, 2011, 05:38:23 pm

745 turbogreasel

  • Guest
Re: Puzzle on return line
« Reply #12 on: April 21, 2011, 05:38:23 pm »
It's a return line, and can't interfere with engine operation(unless plugged) why do you care?

Reply #13April 21, 2011, 10:06:59 pm

rabbitman

  • Veteran

  • Offline
  • ***

  • 2787
Re: Puzzle on return line
« Reply #13 on: April 21, 2011, 10:06:59 pm »
Mine have a little air in them, it stays because there isn't enough flow to push the air down from one injector to the next.
'82 Rabbit, I put on a euro vnt-15, 2.25" DP, 2.5" exhaust, the result.....it whistled.

I removed the turbo, made a toilet bowl 2.5" DP, the result....it was deafening. Now it has a homemade muffler up front and a thrush in the rear, the result.....less loud.
Watch: AGENDA, GRINDING AMERICA DOWN

Reply #14April 22, 2011, 10:15:51 am

mtrans

  • Veteran

  • Offline
  • ***

  • 308
Re: Puzzle on return line
« Reply #14 on: April 22, 2011, 10:15:51 am »
Thanks on replys,
I`ll put same fuel and see,after holiday.
I`ll improve my English