STUCK AND LEAKING

[armagedn]

Hey all anybody have one of the injector line pulse adapter fittings they are willing to part with for a 6.9 or 7.3. Mine split ,but fortunately I was able to limp it home the last 6 miles of my 1150 mile trip.
Thanks,
Armagedn

 

['94IDITurbo7.3]

you could check any local salvage yards.

welcome to te forum.

 

[franklin2]

I believe 6.9's do not use the adapter fitting. When I got a replacement #1 line from a 6.9, I had to take the adapter off my 7.3 for the line to fit properly.

If your 7.3 line is ok, and the adapter is the only problem, just take the adapter off and bend the line to fit without it, you don't really need it. Just make sure all the lines are well supported in their original rubber lined clamps, or you will have cracked lines everywhere. I learned my lesson on that the hard way.

 

[towcat]

.....If your 7.3 line is ok, and the adapter is the only problem, just take the adapter off and bend the line to fit without it, you don't really need it......

wrong.
all of the injection lines are length matched. this also includes compensating the line length for the timing adapter. you can run without the adapter but the cylinder will have an imbalance due to the uneven firing pulse.

 

[icanfixall]

Boy howdy is the above correct. Do not remove that pulse adapter and just bend the line to fit. That cylinder will be way off on the timing compared to the 7 other cylinders. Now as for the 6.9 not having this adapter... Yes, they do have it but its on number 4 cylinder as I recall. Its also on that cylinder in any 7.3 van engine. You can buy the number 1 hard line without the fitting too. The line is made the proper length to fit without bending too. They are around $45.00. I bought one for my engine but I found it was a little small in the diameter and my timing clamp wouldn't fit it. So I went back to my original 7.3 line with the fitting. Now I time off the number 4 cylinder. It seems to time better than the number one cylinder no matter what injector is in the head for the #1 cylinder...

 

[franklin2]

Don't knock it till you try it. My engine runs fine with the 6.9 line on it. If the timing is off, it's so slight it has no affect.

I need someone to explain to me how the line being a different length can affect the timing. I ready to learn something here.

The line is solid full of fuel all the time correct? And the fuel is not compressible correct? So it's like hydraulics. If the pump pushes fuel in on one end of the line, a like amount will be pushed out at the same time on the other end correct?

Let's talk about this in the extreme, and then maybe I will get it. Let's say one line is 10 feet longer compared to the others. It would have a larger volume of fuel to push through this line, and the fuel would have weight to it, and momentum would come into play I suspect. I suppose it would take longer to accelerate and then stop the increased volume of fuel. Possibly there would be a increase in friction in the longer line also.

If this is what you are talking about, I can't see where a 1 or 2 inch long adapter would make that much difference.

 

[Michael Fowler]

^^
Theoretically, I agree with you.
It remains for those with more practical experience to explain why it matters.

Does it matter ( in the real world) how long a wire is? Will a spark plug wire that is 10 feet long, be "late" compared to one that it 6" long?
Of course this is based on the line being filled with non-compressable fuel; systems with air leaking into the fuel will be different.

 

[icanfixall]

I do believe a shorter line will change the timing on that cylinder. Its difficult to put in words just why. So lets try this just once. Liquids don't compress like a gas will but. The line does expand with every pumping of fuel thru them. A longer line will slow down the flow of fuel because its length is more. So that cylinder appears to me to have a retarded timing pulse. Remember that we time these engines of the pulse felt on the hard lines. Or is this pulse an electronic feel.. Nope... Purely mechanical. A 6.9 hard line on a 7.3 engine number one cylinder works fine. Its the same length as the 7.3 line with the rotunda timing adapter. I hope this is not stepping on anyones toes. Its not ment to.. Only to attempt to inform...

 

[franklin2]

Apparently some of these "it has to be that way" and "you can't do that" comes from internet hype passed from one person to another. That's the only conclusion I can come to as to why everyone says it affects the timing, but no one really knows why.

I am still open to the idea that it may affect the timing, but I suspect there is a + or - length that still works. The factory threw these engines together on a assembly line, and everything has a tolerance. The position of the camshaft lobes, the locating pin or keyway on the gears that drive the cam and the pump, even stuff in the pump itself have + or - tolerances. As long as these components are built within the "window", they are considered good enough for the engine to run. I am sure most of you know what "blueprinting" means, trying to take out these factory tolerances and bring them in as close as possible.

I would suspect there is a length tolerance on the injection lines where they will work ok with little noticeable affect on the engine's performance, but I am guessing about this and still don't know for sure.

 

[Brimmstone]

Got a couple sitting in my toolbox. Might even have a 6.9 hard line somewhere. Shoot me a pm

 

[OLDBULL8]

Take into consideration that at 2000 RPM, that that cylinder fires 4 times per second and has only 23 thousandth of a second to inject the fuel. If the timing is set by #1 cyl., then all the other cylinders are off the set timing from #1. Certainly the engine will run, but how efficiently, when you try to achieve the perfect timing. The way to find out is to set the timing at #1, then check it at #4, see what the difference in degrees is if any. Just my thoughts, never did it, but might sometime.

 

[icanfixall]

I have one more thing to add to this hard lie length. This may shead so lite on the length of the lines. A few years back the immissions issues with the 7.3 engine was being looked at closely. The exhaust was dirty so.. It was found that if the injectors were pulled 60 thousands up out of the precups the burn would be cleaner... So the engineering was done to raise the injectors that amount and ALL the hard lines were SHORTENED the same amount. This didnot change the timing but it was done for the fit. So if you removed and just bent the 7.3 number one cylinder line back down to fit your going to be advancing that one cylinder timing compared to the other 7 cylinders. Does anyone have the timing equiptment to test this out... Probably not. I really feel if the bending of the line methode is used you may not actually feel the timing change but the engine will. And that is going to change the power no matter what you think. Matching and balancing all the actions in any engine is going to add power thats been lost because issues are found in every factory engine. We all know about a given + or - tollerance. Those are the "it will run ok here" measurements. Even Eric the Mahle piston ingineer I talked with told me our idi engines can run with a 14 gram differance between pistons and live a long life... So I made all my pistons closer. There is 1/4 to 1/3 gram differance in each piston in my engine. Does my engine run smooth... Well you can hear it run but you can't actually fel it run...

 

[franklin2]

I still can't figure out what it's all about. The fuel is not compressible, it's a solid connection between the pump output and the injector input. It's like saying the valve timing on one cylinder would be off if you had one lifter twice as tall as the all the other lifters.

P.S. With the proper shorter pushrod of course

 

[icanfixall]

I still can't figure out what it's all about. The fuel is not compressible, it's a solid connection between the pump output and the injector input. It's like saying the valve timing on one cylinder would be off if you had one lifter twice as tall as the all the other lifters.