Author Topic: injector/return line  (Read 4282 times)

getterdone

  • Jr. Member
  • **
  • Posts: 57
    • View Profile
injector/return line
« on: March 07, 2007, 05:32:17 AM »
need some information regarding the injector return line. does this return line, the plastic one [on mine anyway] need to be hooked up? it makes it a little more difficult if i have to use it on wvo conversion. the way i see it you would have to have a switching valve here also. any way its in the way to put the heating element in place. i havent seen any pictures of the conversion's or seen were any one has talked about this. the way i see it is it's there just to get air out of the line. am i correct with this thinking? help please!

peterako

  • grazy dutch in Greece
  • Jr. Member
  • **
  • Posts: 91
    • View Profile
Re: injector/return line
« Reply #1 on: March 07, 2007, 02:23:29 PM »
oke lets start from the end.
If you have air in your feeding line there is bad pressure in your feeding line so your engine is not running. so it is not for bleeding air. ;D
The connection is used for any not injected fuel to be returned to the tank. ::)
To help you more maybe in the begin you do not see fuel but after some running time and temperture you will see same drops from here. this is the magic formula from wearing in, temperature and injection time.

You do not have to connectd this but after the first drops in combination with dust you creat a very dirty engine and ready to take fire.

I hoop that this helps you

Greetings from Greece  8)
lovson 6/1 DI backup for my new house using solar heating and power plus a 1000W wind generator.

getterdone

  • Jr. Member
  • **
  • Posts: 57
    • View Profile
Re: injector/return line
« Reply #2 on: March 07, 2007, 03:19:01 PM »
well, you ansered one of my questions; the line is for excess fuel that was not injected into the engine. now that being the case, it is needed, in saying that, shut down time,[on diesel fuel, or bio in my case] will take longer. i guess the best way to have a two fuel system is to have a small filter in place with return line port on it, have a two port valve ahead of the filter. then you can select what type fuel to be used. down side is that, purging time will increse. guess there's no way around it. any other ideas welcome .

adhall

  • Full Member
  • ***
  • Posts: 236
    • View Profile
Re: injector/return line
« Reply #3 on: March 07, 2007, 03:21:13 PM »
Getterdone:

If things are working right, you should only see a very small volume of fuel flowing through the return line.

Why not just connect it back to your WVO tank? True, you would end up with a small amount of your "starting fuel" getting back into the other tank, but given the tiny flow rate and the short amount of time you are running on this fuel it shouldn't amount to much.

If you can't tolerate any mixing of the fuels, you could collect the flow from the return line in another container. (The down side to this is that now you have to dispose of it.)

Best regards,
Andy Hall
JKSon 6/1, 5 kW ST Head, 1992 Dodge RAM Cummins 5.9L Turbodiesel, 2001 VW TDI 1.9L Turbodiesel, 2006 Jeep CRD Turbodiesel, Yanmar FX22D Diesel Tractor

mjn

  • Full Member
  • ***
  • Posts: 116
    • View Profile
    • My Changfa Generator Project
Re: injector/return line
« Reply #4 on: March 07, 2007, 05:01:06 PM »
Hi getterdone,

I ran into the exact same questions when I was putting my WVO generator together.

Don't confuse the injector return line with the injector pump return line.  Lister and Changfa injector pumps do not have a return line. The injector return line catches any fuel which slips past the injector pintle.  On new unworn injectors this is almost nothing.  In over 150 hours on my Changfa I have about 15 inches of fuel collected in my injector return line.

On my generator, I have two 3 way valves, one for the fuel supply, and one for the return from the injector.  The second 3 way valve was a total waste of time and money.

The line does need to be hooked up, but don't bother with a 3 way valve.  All you need to do is route the return line back to your WVO tank. 

Changfa 195 7.5 kw ST.  WVO conversion http://martin.nile.googlepages.com/
Metro 6/1 DI Listeroid. Pumping water for fire control.
1933 Stover CT-1 hit and miss
1936 Farmall F-12 -- unrestored, still used to mow the field

getterdone

  • Jr. Member
  • **
  • Posts: 57
    • View Profile
Re: injector/return line
« Reply #5 on: March 08, 2007, 07:17:04 AM »
well, what i ended up doing was ; i bought a small metal filter with a return line barb. autozone. they couldnt tell me what micron it is though. i assembled it as follows: both bio tank, and wvo tank lines to the three port valve. the valve i used is off a refridgeration gage set. removed gages plugged there holes and you have a nice manual valve. mounted it upsidedown where the cast filter was. center port to the small filter, and there you have it. i had a heater strip about 2 ft. long, wrapped the injecter and line back to the pump. along the line i added a temp sencer bulb attched to a thermostat. i can adjust the temp exactly where i want it. sence i have plenty of length of heater i'll wrap some of the wvo line going to the valve. havent tried wvo yet , to late, tomorrow morning batt. bank will be lower then, as to put some load on the 6/1. hey guys i'm loving it. thank's for your help.