Looking for Some Sage Wisdom, 85 F250, 6.9IDI

These engines are heavy. Make sure your engine stand and lift can pull 1000 pounds. This is no small block Chevy.

DaveBen said:

These engines are heavy. Make sure your engine stand and lift can pull 1000 pounds. This is no small block Chevy.

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Yeah, I remember seeing that engine alone was something like 986lbs. Like 1/6th of the truck's overall weight lol. But I was planning to pull engine and trans together, so I can clean up the trans, change the fluid, and maybe replace the clutch while it's all out. Plus fix the issue with the shifter pin. The 7.3 swap is looking like a strong contender. I'm not getting any movement from the 6.9 after a day of drowning in diesel.

I did pressure wash the majority of the truck yesterday, to get all the filth off, and she cleaned up rather nicely. I'm rather impressed.

I'm still on track to start disassembly this weekend.

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I am getting error when I click on your links. Post the web addresses and not the titles.

DaveBen said:

I am getting error when I click on your links. Post the web addresses and not the titles.

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Sorry about that, I used the little thing to attach images from an album.

https://www.oilburners.net/media/pressure-washing-part-1.792/

https://www.oilburners.net/media/pressure-washing-part-2.793/

Austin Centurion said:

Plus fix the issue with the shifter pin.

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Several years ago, I ran into this on another guy's truck. He was in a hurry and wanted it fixed yesterday. I took a bolt that was about the right length and ground it down on a bench grinder, keeping it as round as I could. When it was slightly larger than the hole where the pin goes, I tapped it into the hole with a hammer and chisel. I left it slightly large so that it wouldn't vibrate out. It didn't work like new, but there wasn't much extra play in the shifter when I was done. I never heard otherwise, so I guess that it worked fine for as long as he kept the truck.
Although all of the externals will interchange between the 6.9 and 7.3, the IPs are different. they are the same, externally (I believe), but the internals are different. One will wok in place of the other, but the 7.3 one puts out more fuel, even N/A stock.

I think I'm gonna tear down the top end of the old IDI eventually. I mean, it's already f***ed, can't f*** it anymore. Or at least that's my view on it. Maybe I'll figure it out and get it spinning again.

Maybe I'll find out that it's something worse than I originally thought and that'll be the final nail in the coffin for this thing and push me further along towards a 7.3.

Or, fingers crossed, it'll be easier to get it spinning again, and from there I'll throw some new head gaskets on it and toss her back together.

Until then, I'll work on all the other things that need doing. Again, 1000 times thank you to everyone. I'll keep posting status updates as I work along through this.

Since you're into it this deep already, now may be a good time to think about installing a ZF5 if you want to. That's how my 1985 is set up. 7.3, ZF5, 3.55 gears (3.50? 3.54? whatever number they happen to be). I works great for a highway cruiser.

IDIBRONCO said:

Since you're into it this deep already, now may be a good time to think about installing a ZF5 if you want to. That's how my 1985 is set up. 7.3, ZF5, 3.55 gears (3.50? 3.54? whatever number they happen to be). I works great for a highway cruiser.

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I looked into a ZF5 after your recommendation. Definitely a consideration for this project. Much cheaper than a Gearvendors.

One of the things I added to my big list early-on as a long term goal, was a turbo kit (Banks, Hypermax, etc.) or I've seen some refurbished factory kits going on Ebay. To improve the get-up-and-go factor. I have a replacement mechanical lift pump, that I ordered early on when I thought this was going to be mostly a maintenance project and some other TLC, but I think that'll get replaced with a Facet pump that I read about in this awesome thread: https://www.oilburners.net/threads/...th-a-facet-duralift-electric-fuel-pump.54496/

I want to keep the 4.10 gears, just to keep things simple-ish, especially if this thing does end up towing something ever again. It's already got a limited slip, the seals aren't leaking, so I figured I throw some fresh fluid in it and a Lubelocker gasket and call it good. So a 5th gear would definitely be handy if this thing is going to cruise down the highway, .
Gotta have something for those big Ikea runs down to Dallas in the future. But it's going to spend most of its time running around suburban OKC, making Home Depot/Lowe's runs, especially when we get a house of our own and move out of the rental.

I got the rear 2 bed bolts out, the front 2 are pretty rotted and will need to be cut out, but I'm out of cutoff discs, at that point I'm going to cut the middle 2 out as well, because they are a PITA to get to with the tanks, fuel tank selector, and brake lines in the way. I don't want to open the brake system up yet, they somewhat still work, which makes moving it around a little less sketchy with my driveway being at an incline.

Tore most of the top end of the engine down. Took the water pump, fan, and fan clutch off as one assembly. I was shocked to see that there is actually still fresh coolant in the block from the thermostat down. Everything above that was pretty rusty, but it cleaned up easy with a gasket scraper and some carb cleaner. Still going to flush it out before I put the new coolant in.

Injection pump, injection lines, and gear housing came off together, couldn't get to 2 of the nuts to pull the IP by itself. I'm hoping this will allow me to keep the engine in time easier, should I want to put it back together. I don't have a balancer puller, so that'll have to wait. But so far so good. I'm going to try one more trick to potentially unstick the rings that are possibly stuck, before I go about pulling the intake, valve covers and heads.

If that doesn't work, then it's getting stripped.

I would not recommend the facet pump. Many people on this forum have found they do not supply enough fuel for these engines and some have found the screen bowl invites air intrusion issues.There are several threads talking about this as well.

Austin Centurion said:

Injection pump, injection lines, and gear housing came off together, couldn't get to 2 of the nuts to pull the IP by itself. I'm hoping this will allow me to keep the engine in time easier, should I want to put it back together.

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Not since you're going to turn the engine over (assuming that it will). You have no way to get the cam and IP gears back in time. Get ahold of a balancer puller, pull it off, then remove the front engine cover. When you start putting it back together, you can get the cam gear in the right place, then put the IP gear back on, and finally bolt down the IP gear cover that way there's no way that the gears can come out of time. When you put the front engine cover back on, all you have to do is slide it up in the groove in the IP gear cover. It's a little work, but not really too bad.

Pulled the valve covers today, let me just say that the valve cover bolt for the left bank, the bolt in the back under the heater/AC box is a PITA. With that said, after pulling the valve covers I am a bit shocked.

This engine looks clean as new on the inside. Rocker arms and push rods look mint. No glazing or anything that I've seen when pulling the covers on some higher mileage gas engines, so maybe that's just how these things are. No real signs of excessive wear on the rockers. Everything looks good as far as the valvetrain goes, so maybe the 126k on the odometer is accurate. I'll have to remember to take some picture of this thing next time. I always forget, especially when I'm covered in the 'schmoo' that this thing is covered in.

After seeing some threads here discussing how these head bolts are reusable (because replacements are hard to find and not cheap for some reason, and at this point I just want to get it running), I'm going forward with pulling the heads. Maybe this thing just wants some manual persuasion and a little "heat and beat" applied to free it up. Worse case scenario, to redeem this 6.9, I'll pop the pistons out with the block still in the truck, and see about replacing the rings, or getting some standard sized replacement pistons. And giving the bores a quick little drill hone to freshen them up.

Philip1 said:

I would not recommend the facet pump. Many people on this forum have found they do not supply enough fuel for these engines and some have found the screen bowl invites air intrusion issues.There are several threads talking about this as well.

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Thank you for the feedback on that, good to know bits of information like that. Would something like this Carter pump be a better option? https://www.amazon.com/dp/B000CIU8I...4W&psc=1&ref_=lv_ov_lig_dp_it&tag=coa_us_g-20

Seems like it flows quite a bit more at the same pressure range, and it doesn't have the same filter bowl that can lead to air intrusion issues. Adding an electric pump is still a bit in the future, but I'm a planner and I like having a game plan for things well in advance.

In other news, I filled up the tires yesterday, they were pretty low, like 10-20psi at all 4 corners. Pumped them up to about 40-45 with the compressor. And, of course with my luck, come outside this morning to one on the rear blown out. That's what I get for hoping that some 10+ year old dry rotted tire would hold air for more than 24 hours.

Also, I'm sorry that this is kinda slow going. It's been pretty hot here lately, so I try to do most of the work in the earlier hours, but today I decided to sleep in a bit, so I didn't get much time to work on things before my shop gloves were starting to fill up with sweat. Heads will most likely be coming off tomorrow.

You can get the front pistons out with the engine still in the truck, but you won't be able to get all of the rear ones out. They also won't come out of the bottom of the cylinders. There's no "in frame" work on these like there is on the bigger diesels. They're more like an oversized gas V8 engine. A word of warning, the heads are about 100 Lbs a piece so if you try to lift them manually, be sure to eat your Wheaties first.

People seem to use the holley series (red, blue and black) the carters were a very good option however I've heard the new ones are having reliability issues where the quality is hit or miss. I personally am using the holley black pump because im running a bigger pump. The blue and black flow more but also require a pressure regulator where the red does not and that leads the holley red pump to be popular for near stock applications.

If you’re going to pull both heads, recommend pulling the engine. The time save getting the work done, and frustration, are worth it.

stealth13777 said:

If you’re going to pull both heads, recommend pulling the engine. The time save getting the work done, and frustration, are worth it.

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I'll STRONGLY second this. Plus, if you decide to pull the pistons, the engine will have to come out anyway so you'll actually be saving yourself time there.