Bleeding Injector lines?

[marand9199]

Does anyone have a better way to bleed the fuel lines from the pump to the injectors then cranking on the motor? I've been cracking open the nuts on the injectors one at a time now for 3 days, on and off, and I can only see fuel coming out of 5 of the lines. The reason for bleeding the lines is I put a new pump in. There'a got to be a better way!
Anybody?

 

[andy3]

Are you getting any out of that line if you crack it at the hydraulic head?

 

[Iceman3005]

Try starting from the fuel filter first, crack the screw on the top of filter, once you have fuel there close it. I then crack open cylinder #2 fuel line and start cranking, once I have fuel there I close it. Then I crank till it starts, usually it only takes about 30 seconds to a minute of cranking for it to start sputtering. This method has always worked for me when I work on the fuel system.

 

[Hasdrubal]

"Ditto" on making sure the filter is first purged of air. Then I would remove the glow plugs, makes it easier on starter and batteries. Put a piece of cardboard an each side inner fender, shows spray marks well and makes clean up effortless. Then loosen all 8 injectors at the same, take care your cranking cycles are short with cool off time for the starter in between. Tighten the injectors as they show a good spray pattern not just a little spitting.

 

[Iceman3005]

Yes, I should mention after 30 seconds of cranking I let starter cool for 2 minutes.

 

[Warthog]

The only way to get fuel from the IP to the injectors is to crank the engine. The pump has to turn to get the fuel down the line.

The above suggestions are correct. You can also remove the glowplugs while bleeding the lines. It makes the cranking easier.

 

[marand9199]

Thanks Guys!
I might not get to it until Sunday but I’ll post my progress.

andy3:
I can’t get to the hydraulic head with the manifold on but I’m getting fuel to some of the injectors so it must be good.

Iceman3005:
What is the significance of the #2 fuel line compared to the rest of them?

 

[Floridianson]

I have cracked maybe two on both sides and not removed the glow plugs. The old lady cranks it over and when it starts just start closing them.

 

[Iceman3005]

#2 fuel line is the shortest one, I have noticed if you try to bleed the rear fuel lines it creates an air lock in the shorter ones, this is just my oberservation so far. I should also mention I have someone help me, they crank while I crack open #2, once I get fuel I tighten it down. Usually the truck start's to sputter when I tighten #2 down. My theory is getting #2 purged of air the rest follow without bleeding, works about the same when I do the brake lines, I start with the shorter one, once I get to the back brakes not much bleeding is required.

 

[Hasdrubal]

Isn't 30 seconds of cranking too much? I don't think I ever used longer than 10 second intervals.

 

[marand9199]

I agree, 30 seconds sounds like a long time. If the glow plugs are removed no problem, if not, I wouldn't want to blow out my new starter.
10-12 seconds I like.

 

[Iceman3005]

If you look in the TM it states that 30 seconds of cranking is normal, followed by 2 minutes of cool down.....then repeat.

 

[firefox]

I would like to thank Iceman3005 for the following excellent advice, which
was spot on.

"#2 fuel line is the shortest one, I have noticed if you try to bleed the rear fuel lines it creates an air lock in the shorter ones, this is just my oberservation so far. I should also mention I have someone help me, they crank while I crack open #2, once I get fuel I tighten it down. Usually the truck start's to sputter when I tighten #2 down. My theory is getting #2 purged of air the rest follow without bleeding, works about the same when I do the brake lines, I start with the shorter one, once I get to the back brakes not much bleeding is required."

Bruce

 

[phil2968]

The injection lines on diesels are all the same length. They have to be or the timing and injected amount of fuel would vary from cylinder to cylinder. Look at the first couple of lines of the deuce multi fuel and note the spiral loops because those injectors are close to the pump. Number 6, not so much!

 

[firefox]

Maybe the reasoning behind the advice is flawed, but just bleeding the #2 line clearewd the problem right up. Maybe I just got lucky and bleeding any line would do the same thing,
But I have a feeling there is more to this than line length.

Well, I am happy with the results, regardless of the reason behind it. Time will tell.

Bruce

 

[grunex125]

Don't know if this helps much in this situation but this past week we had a 478 Hercules run out of fuel in a White farm tractor,(bad fuel guage) couldn't get it to bleed up through the system by way of the hand pump, so we found a place where we could splice in a 12v lift pump in the line, made contact with the battery, let it pump while we cracked open the filters, and bled the line right up to the IP. Got in cranked it with the lift pump still pumping, and it fired right up! no need to crack injector lines, just kept the lift pump running while purging the system which only took about 10 seconds. after that no more need for a lift pump so we removed it and chalked the rest up for experience. As I said I don't know if this will apply here much, but maybe it will help somone out. I do apologize for the hijack. best of luck to you gents.