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Discussion Starter #1
Hi, I dont like the original fuel injection lines, they are in the way when working on the valve covers.
Would it be possible to make new ones?
What are they made of? steel?
Whats the pressure in the lines?
Would be a bad idea to make them of copper or will it crack?

Per
 

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jimmy6.2;1889211; said:
Hi, I dont like the original fuel injection lines, they are in the way when working on the valve covers.
Would it be possible to make new ones?
What are they made of? steel?
Whats the pressure in the lines?
Would be a bad idea to make them of copper or will it crack?

Per
And where would you put them? They need to be all of equal length - because line length affects timing. Not only does the length of each line need to be the same, the total length affects timing. If you make them longer, or shorter, you'd then have to figure out how much the timing has changed and compensate for it.

The OEM lines are thick-wall steel and rated to at least 15,000 PSI burst pressure. Copper is a really BAD idea. So is changing length. And, if you DO change length, you have to get them all the same length, get them tie together to keep them from suffering vibration-cracks, etc. etc.

My general thought is - if you don't like the lines going over the valve covers - get a different diesel. Maybe an in-line Cummins. Even a Ford 6.9 or 7.3 is a little different since the injectors are closer in and vertical.
 

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I thought they were ceramic lined?
 

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Discussion Starter #5
The OEM lines are thick-wall steel and rated to at least 15,000 PSI burst pressure. Copper is a really BAD idea. So is changing length. And, if you DO change length, you have to get them all the same length, get them tie together to keep them from suffering vibration-cracks, etc. etc.
15000 psi = 1000bar

What is the pressure inside lines? not a 1000bar i guess.
 

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Typical injection pressure is around 1500 psi. That isn't a constant pressure, of course. That is a pressure pulse when the injector is supposed to fire.
 

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monz;1892225; said:
Typical injection pressure is around 1500 psi. That isn't a constant pressure, of course. That is a pressure pulse when the injector is supposed to fire.
Depending on what year 6.2, the pressure can be set as high as 1950 PSI (134 Bar), with the older long injectors being set at 1500 PSI when new, and as low as 1350 when used.

Many other IDI diesels have injectors set at over 4000 PSI, and a few diesels run injector pressures at 19,000 PSI.

Injector lines are prehardened on the inside,usually by being subject to very high pressures when new - sometimes 50,000 PSI. Line strength is not just about PSI, it is based on "compression-pulsating-fatique" strength. So it gets pretty complicated.
 

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I wouldn't recommend it. The lines are pretty special. It would be much better to just live with the existing lines if the only thing you don't like about them is that it makes it hard to get to the valve covers.

As jdemaris noted there are variations in injection pressure depending on application, the year of the engine, and how many miles are on it. The pressure generally reduces somewhat as the engine is used. Comparatively all of the pressures mentioned above are pretty low. Modern diesels use injection pressures many times higher than the pressures mentioned above. Some of them are now using pressures as high as 80,000 psi.
 

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jimmy6.2;1892537; said:
I understand that I cant use any lines, but it must be possible to get or have made.

Per
One thing a guy could do, although it requares a little bit of bending of the lines at that point, is to have an extra connector put in the lines where they come out of the intake manifold. i think a diesel pump shop would have these connectors, i never asked if they have them ,but i have been toying with that idea of and on myself. Down in my old country I worked for a shop where we made up a line when one broke, we never installed OEM, was to expensive .

I wonder if it is worth the time and expense for the odd time the valve cover has to come of.
 

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exactly, not worth the time and expense for something thats not removed that much, or at least should not need to be.
10+ yrs on one of mine and the covers have not been off.
 

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This is one area that should remain as the factory designed it. Too much went into the design, including a way to remove and replace them. As stated, it's not that much of a problem, given the amount of times most need service.

Modern sealing technology has all but eliminated oil leaks or at least made them liveable. Engine problems on the older 6.2's are on the low end of the scale as well. Most folks don't have to remove these lines very often, if ever.

If we keep our vehicles forever, we wll need a 5/8", 12 pt. crows foot, sooner or later! I'm still using the J-tool that came with the GM Essential Service Tools package, in the fall of '77 for the 5.7D's!
 
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