Looking for Some Sage Wisdom, 85 F250, 6.9IDI

Philip1

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Hopefully I'm wrong but from what I understand, the 6.9, 7.3, and 7.3 idit used different flywheels to compensate for changes in the internals. Its also possible that some (or all) smf manufacturers have adopted a "universal" flywheel that can cross between some of the engines.
 

IDIBRONCO

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It may have vibrated more than it should have and I couldn't tell either. I don't seem to have much out of the ordinary vibrations now that it's on a 7.3. It's been on there for over 6 1/2 years and I can't really remember how it was on the 6.9s. I just didn't notice anything excessive.
 

Austin Centurion

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Okay, it's been a while. Longer than I anticipated. We got hit with an ice storm on the weekend I planned to get things done, and when that finally cleared up, the hydraulic ram on the engine hoist had crapped out. So, I ordered a nicer replacement ram, a Big Red unit, same rating, but quite a bit beefier (1.5" piston compared to the 1" piston of the original, plus weighs about twice as much, more meat in the base and ram) and easier to use compared to the original from HF (moves faster per pump, and is more controllable when lowering). Then, it took way to long to get enough people together to help move the massive engine pack out of the garage.

With 6 people, including myself, assembled, and after some dancing around and magic (had to unbolt the hood springs and do some up/down dancing with the engine, adjustments of the leveler, etc) Now, It's finally back in, in all its glory. Apparently it was quite the show, because some neighbors came out to watch, and some passer-bys decided to slow down and rubber neck a little. Gotta love suburban neighborhoods.

None of my assistants were really tech savvy, mostly just free muscle, so I was running around making sure things were clearing and getting mounts lined up. I'm rather proud of my ability to get the transmission mount dropped into the crossmember by just eyeballing it and using the leveler to drop it into place.

That ice storm did some funky stuff, mainly with what items were in the bed, none of which are incredibly vital, including the old engine. In my haste to get things moved around in the garage, so I had space to clean up the new engine, I never fully drained the oil and all the diesel that I dumped into the old 6.9, so when the rain started pouring, and then freezing, it filled up the open cylinders and valley with quite a bit of ice, and then started displacing all the oil to leak out of both the front and rear main seals. So my truck bed, and driveway got a nice coating of dinosaur squeezings, which I then had to crawl in while installing the new engine.

But, after all that hard work, this was the big step that needed doing, it's finally done. So now I can move forward with ALL the little stuff that needs doing. I already got the transmission squared away with a fresh dowel pin for the shifter, a new shift knob, and fresh gear oil. And I got the new battery cables installed in their relative positions. All the wiring for the engine itself is reconnected. But that leads me to my next task.

I did crank the engine over a bit just using the crank and a socket, to make sure that the new fresh oil and additive could be circulated around before it actually starts. But I wanted to see if I could get it to turn over with the starter after doing that. I hooked up all the cables, new starter solenoid, new batteries, and got everything where I thought it should be, but got no power in the cab and no response to the key. So I'm guessing I missed something. I have a new 3G alternator, which is installed, but I haven't wired it in yet, I have a Painless Wiring 3G wiring kit, because I SUCK at electrical wiring and wanted something simple, but is the alternator a part of the power circuit? Meaning, does the alternator NEED to be wired in for the rest of the system to get power? This is the guide that I've found for the swap, but automotive wiring just goes over my head for some reason: https://www.ford-trucks.com/forums/1506233-130a-3g-alternator-upgrade-on-6-9-7-3l-idi-guide.html

Once I can figure that out, and get the thing cranking/running, I can bleed the air out of the injectors and see how this thing idles.

After that is done, its just a matter of replacing u-joints + a center bearing (the whole rubber ring is pretty much torn and gone and I'm struggling to figure out the correct one I need), filling and bleeding the clutch, getting tires on (I don't know how I'm going to manage to afford that until next year), and all the other items I've detailed in the past (brakes and suspension issues mainly) so I can FINALLY get this thing moving again.
 

Austin Centurion

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Well, I'm dumb, I went back through and checked my work, and did some basic Googling. I forgot to plug in the neutral switch for the transmission. And there's a safety switch for the clutch pedal. But I have power going to the cab now. I must have bumped something the right way. I was able to get it cranking over by jumping the relay, got great oil pressure on the gauge after cranking it over with the starter for about 10-15 seconds and even my fuel gauge works properly! I'm hopeful to have it running under it's own power today or tomorrow just to make sure everything is fine. Then I can attach the exhaust, and button up the front end and fill it with coolant.

Now, I just have to do some wiring for the alternator....
 

Austin Centurion

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Sorry for the long-term radio silence. Not much as really progressed with the truck lately. The weather and work has kinda put a damper on most things that need doing. I've gotten most things that need doing done, it moves under its own power, although I haven't moved it very far. Reversed it about 3 feet just to test that the clutch is indeed bled and works properly. It pulls itself up the hill of my driveway at idle. I love the meaty idle that it has, little bit of rumble in the cab and just chugs along happily.

I finished rebuilding the driveshaft, and reinstalling it. There's still an issue with feeding it diesel from the new front tank, which I'm suspecting has something to do with the tank selector valve. So I've been feeding it via a length of hose going to the 5 gallon jug I have. I've yet to determine if I want to omit the tank selector entirely. And just run new hose directly from the tank to the pump and then new hose from the return back. Or get a cheap replacement online and see if that would work.

Its still air cooled, until I get the front end put back together. Then I can get the new Mishimoto radiator installed and get it filled up with coolant.

The plan is to move it soon, and flip it around in the driveway so that it's facing into the garage, thus making it easier to put the front end back together. That'll be a team operation as brakes are still rather non-existent, so I'll need someone to grab the chocks out from under it, and then toss them back under when I get it flipped around. The lady of the house wants her spot in the garage back, so working to clear that up and then move the Mustang back over to its spot.

I finally got a replacement tire to deal with the driver's rear blowout that happened when I aired up all the tires for the first time. Went with a 235/85R16 Pro Comp A/T Sport. Nothing fancy, but it's a sturdy tire and looks more at home on the truck compared to the 265/75R16s that were on it. Still needing to replace the other 3, but that'll happen after Christmas sometime.
 

Austin Centurion

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Well, we got somewhat snowed in, or at least enough snow/ice to make me not want to crawl around the truck in the cold for the past few days. But I think I got my plans set for after Christmas. I'm going to bypass the fuel tank selector entirely, and just use the front tank for the time being, and run 3/8 hose from the tank, to the mechanical pump and replace the leaking return with a section of hose directly to the tank. I think that is 5/16 hose, but could be wrong. I've gotten tired of running the thing off a 1 gallon jug bungee'd to the core support and want to be able to put the front end back together and finally get the radiator in.

I did some research, saw IDI Performance's non-bypass style fuel system but didn't like the price-tag for right now. But I got to thinking about a future change to make bleeding the air from the system less of a PITA (I've done it 3 or so times now while tinkering with the fuel system trying to figure out or somehow magically get it to work again) and potentially improve the system. I've learned that the stock fuel filter setup kinda sucks, but I plan to keep it for the time being while changing over to a Holley Red Pump tucked into the passenger side frame rail. Eyeballed some hose routing, from the tank, up the driver side frame rail, across the transmission crossmember, and then up the passenger side to the pump, then from pump to fuel filter hat. The red maxes out at 7psi, so it shouldn't need an external regulator.

Now, I've seen a lot of people saying that it's not possible to retain both tanks without the selector valve. But I was still planning on swapping out the rear tank eventually (after what I found in the front tank, I can only assume that the rear is worse). I was wondering if it would be possible (after swapping the rear tank), to Macgyver a fuel system using T-fitting for the feed from both tanks, and a T-fitting for the return to both tanks. And have the feed setup in such a way that if 1 tank were to ever run empty, there'd be some form of check valve in the system to prevent it from pulling air. If that's just not feasible, I might just go the route of getting one of those universal selector valve kits (valve, pigtail, switch). But all this is for after I get everything else to the point where it'll go down the road straight, smooth, and stop.

I was going to start accumulating parts to tackle the rear end (brakes, suspension, bearings+seals, and fluid), but there are a lot, and they ain't cheap so I think I'm just going to address the power steering system first, it's a cheaper project and it'll allow me to move this thing around a little easier. Needs a pump, new hoses, and some fresh fluid. Easy haul from Amazon and a couple hours worth of work. Once that is done, I shouldn't really need to fiddle with much more under the hood.

I finally have established a deadline for this to be roadworthy (tires, suspension, and brakes done front and rear), and that's due to our lease being up next August and us planning to move into a more permanent living arrangement. So, as long as it is ready enough to drive itself to our new home, I'm happy. If it's able to pull a trailer and haul some furniture and boxes, I'll be ecstatic. I'm going to start at either the front or back first,sometime beginning next year, when the funds are there and the weather isn't miserable. I'll keep getting Discount Tire to swap out old tires every month or two until then.

Stay warm guys, Merry Christmas, and Happy Holidays to you all. Look forward to more progress early next year. :cheers:
 

IDIBRONCO

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You're right thinking that the return line is 5/16". I've bypassed the FSV on my Blue Truck. Instead of trying to become Mac Gyver, I'm just going to replace my leaking rear tank and then use an electric transfer pump to pump the fuel from the new tank into the front one. The issue that I could see about using T's like you suggested is that there'd be no way to guarantee that the fuel is returned equally to both tanks. If it's not, eventually, you'd be overflowing one tank. At least that's the way that I see it.
 

Farmer Rock

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The previous owner of my f250 bypassed the fsv and selector switch,and just used the front tank.I thought about ways I could connect the two tanks,or like IDIBRONCO said,use electric lift pumps,but I am leaning towards installing a bronco tank,so it is only a big single tank.Might be worth looking into.



Rock
 

Austin Centurion

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I really like the idea of using a rear tank as an onboard transfer tank. It's cleaner looking than a bed mounted tank. If I end up doing this with mine, I might use CDD's 38gal rear tank and sump kit, so I can get the tank, sump and sender all in one go. Then just use a micro diesel pump, like the Edelbrock or Mr. Gasket, and have it pull from the sump up to the front tank's return. And the engine can return to the rear tank. Might take that into some more consideration once I get the thing more road worthy.

Well, I got the thing all back into a truck shaped moving vehicle. Grill is back together, and the core support is in. I never was able to find a replacement or have someone come repair it, so I just slapped it back in for the time being, it has a brand new poly mount setup on the passenger side, and a wooden block holding up the driver side. It's not perfect, but it does keep the front more level than it was before. So it doesn't look like it had a severe stroke. I still don't know how images work on this site, but I'll do my best to include one below:

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The parts for my power steering came in, so I'm getting that done soon. But I got excited with some Christmas presents and got new cab lights installed. To go with the nice new headlights:
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If the pictures don't show up, I posted them in my media gallery: https://www.oilburners.net/media/albums/1985-f-250-centurion.79/

Now, I just have to get the bases of the front turn signal bulbs out of the sockets, because the bulbs came out but the bases are corroded in-place. I already have new LEDs for the entire thing, and a new flasher module. Even new side marker lens and LEDs, so it'll be nice to see it all lit up.

Random Fun Fact: The horns on the roof do work and are wired into the horn switch on the wheel. They're pretty pathetic sounding though.

The tail lights are another story, I have new bulbs in, and just got my new lenses, but there's something screwy with the wiring and I don't get reverse or brake lights. This thing has a whole mess of wiring from the cab back. It has a trailer hookup in the bed for a 5th wheel or gooseneck, and then a traditional trailer hookup by the rear bumper, but the wiring is a mess of T-taps and crappy wiring. I'm dreading the thought that I might have to cut all of it out, and rewire the brake and reverse lights back into the chassis harness properly and then figure out a better trailer wiring hookup. I think I'm going to keep the bumper that's on there now, and just throw a ball on it, as I don't plan to tow anything bigger than one of the larger uHaul trailers with this thing, and that should be enough. The bumper itself seems sturdy, with either 3/8" or 1/2" plate steel used for most of the structure.

I put the interior mostly back together. After installing new dash bulbs and after screwing around for an hour trying to remove the headliner that's basically just turned to dust, I found that it's holding up all the wiring going to the Centurion roof console, so I didn't want to have all those wires dangling around, especially because I can't figure out what the 4 toggle switches on that console do, and the CB Radio is shot. I also tossed the ratty old seat cover, to find a somewhat tattered and faded Saddle colored front bench. Dark red interior everywhere, but saddle colored seats seems a little odd to me, but I don't mind it. Eventually the front and rear bench is going to go, and I've decided that I'm going to get Corbeau buckets one of their bench style brackets for the front and just have storage space in the rear. After the majority of the floor pan is replaced though. Because while cutting out some of the really nasty old carpet, I found quite a few "speed holes" that are going to need attention... eventually. And not by me, I'm going to let a professional handle that... someday.
 

IDIBRONCO

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Why are you going to run off of the front tank and have the fuel return to the rear?
 

Austin Centurion

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Why are you going to run off of the front tank and have the fuel return to the rear?

It would save having to drill an extra hole in the front tank from my thinking. Unless I had some kind of Y-fitting going to the return port on the front tank's sender. I figured I could use the rear tank's feed side for the transfer pump and have the transfer tank pump into the front tank's return port. Here is my terrible MS Paint thought process:
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And now that I think of it, I could still use the tank selector switch to check the level of the transfer tank in the cab, without it actually switching the tank.
 

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