Are 6.9/7.3 injector lines interchangeable?

[smolkin]

In the process of swapping the IP from the 6.9 to the 7.3 I discovered a "repaired" hard line that I don't like (it has a brass tubing union on it). Can I swap the hard lines too? The 7.3 has the timing adapter on #1, would the 6.9 lines work if I removed it? I was reading this tech article http://www.oilburners.net/forums/showthread.php?t=7639 which mentioned the 7.3 lines being slightly shorter...that shouldn't matter if I do the whole set, right?

 

[franklin2]

Yes, if you take the timing adapter off the #1 injector, the 6.9 line will fit. I have a #1 6.9 injector line on my 89 7.3.

 

[smolkin]

OK new problem. To recap I'm putting a newer IP from a '84 C6 6.9 onto a '90 E4OD 7.3. I'm swapping over the throttle sensors, remove the VRV and FIPL, and the levers are different!

Old pump (had E4OD/FIPL)

You must be registered for see images attach

New pump (had C6/VRV)

You must be registered for see images attach

Is there a way to mount the FIPL on the new IP? Is it a part that is interchanged? Or have I got myself into a mess?
I gotta get this done, need truck tomorrow.

e: It's the cross-piece on the new IP (bottom pic) that's the problem, it's too long for the FIPL socket. Can I file/cut it?

 

[towcat]

the roll pin for the VRV can be driven out and the FIPL blade is installed in it's place.

 

[johnnyb1]

I think I had to change that on a 7.3 IP. No problem. Hope you get it fixed.

 

[smolkin]

The part in question is held on by 2 3/32 Allen set screws that are rusted pretty good. I'm hitting it with wd-40 every few minutes, but so far I don't think they're coming loose before I strip them. Is this a part that you can get from a Stanadyne dealer? Gonna call and see tomorrow I guess.

 

[icanfixall]

Just remove the roll pin and install the tps driver wedge. Its that easy. Also set the voltage on the center green wire at .96 to 1.2 volts at idle engine off.

 

[smolkin]

OK, now I have a new piece from Test Calibration. But:

The guy (who built this pump, who I trust) there is telling me there are differences internally between 6.9 and 7.3 pumps. He said turning up the fuel will help compensate. So, although I heard it discussed here many times, I can't find a old thread on here where they say how to do it. Do I turn the fuel screw counter- or clockwise? I'm gonna start with 1 flat just don't know if that's in or out! Right now with the pump off the truck it's easier to adjust it. Anyone have any advice on this?

 

[icanfixall]

The advice is not to turn up the pump without a pyro but... I'm thinking your going to do it anyway so. With the pump off the engine see that "home plate" looking cover on the passenger side. It has two 1/4 inch hex nuts holding it on. Clean off the area and remove cover. Install a 5 32 alen wrench and turn it in just like any normal right hand threaded screw. Make sure you use a new and a quaility made allen wrench. Soft cheap overseas wrenches wont do the job. This thread takes plenty of force to turn. Your turning the internal screw towards the front of the truck to increase the fuel delievery. The internal parts thats differant between the 6.9 and 7.3 pumps probably wont be felt by you or your seat of the pants dyno.
As for the 6.9 injector lines being shorter than the 7.3... Maybe. Thats because as far as I know the lines were shortened by 60 thousands way back in the very early 90 or 91 year for emissions requirements. Its nearly impossible to look at a line and know if its a 6.9 or 7.3. Probably all being made today are shortened. The factory shortened them because they lifted the injectors 60 thousands out of the precups for emissions standards. Such an easy machining step too...

 

[Agnem]

In the process of swapping the IP from the 6.9 to the 7.3 I discovered a "repaired" hard line that I don't like (it has a brass tubing union on it). Can I swap the hard lines too? The 7.3 has the timing adapter on #1, would the 6.9 lines work if I removed it? I was reading this tech article http://www.oilburners.net/forums/showthread.php?t=7639 which mentioned the 7.3 lines being slightly shorter...that shouldn't matter if I do the whole set, right?

Yes, you need to have either all 6.9 lines or all 7.3 lines. Mixing them will result in inconsistent timing between cylinders.

 

[smolkin]

Well, the pump is stock atm, I haven't messed with anything except the adapter for the FIPL, so should I turn it up? I like the fuel economy that the 6.9 had, but it wasn't as fast as the 7.3 was even with the leaking IP, and not sure of what kind of mileage it was getting because half the fuel was pouring out! Will a 7.3-spec IP flow more at stock setting than a 6.9-spec?

 

[hesutton]

No pyro, no go on turning up the IP. The difference is negligible and will not be noticed when driving the truck. A more noticeable issue would be the timing of the IP once it is installed. Like stated above, 6.9 lines work great on 7.3 IDI's as long as that timing adaptor is off the #1 injector. I've had nothing but 6.9 lines on my 7.3 (in the F250) for years and years.

Heath

 

[smolkin]

No pyro, no go on turning up the IP.
Heath

Gotcha. OK then, not adjusting fuel screw, beginning re-installation, thank you everyone for your help!

e: I don't fault the guy at Test Calibration for telling me to turn it up, I think maybe he thought I have a turbo on the 7.3, he just called me back to say he had turbo-6.9 adjustment instructions that said 1.5 flats turned up. In a conflict between info from OB and anywhere else, I'll always go with the OB advice!!

 

[smolkin]

Last post just to say I got it running, just gotta tweak the timing a bit. It's a little down on power, harder to start than it was. IP is set about half a dime to the pass side of the center mark. Is it retarded maybe? Well at least I have a working truck again!

The '84 is now decommissioned, if anyone wants it PM me, no room here for a parts truck. It just needs an IP and some gps, I'll fix those as I have time.

 

[franklin2]

Here's the best article that tells you how to adjust the pump.
http://www.members.shaw.ca/k2pilot/Injection pump adjustment article.htm

Basically, if you are not blowing any black smoke at full throttle, you can turn it up a little bit. You don't want to be blowing lots of black smoke, that's when you are going to damage the engine. Being conservative is the key. Some people like too much of a good thing, and turn it up too much.