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I couldn't imagine being right there, especially with seals in hand, and not changing them wile it's like 1% the work as compared with engine in truck. You need to research IDI rear main seals and learn about your options.
Here's your start;
Google: 7.3l IDI rear main seal options
AI Overview
For the 1983-1994 Ford 6.9L/7.3L IDI diesel engines, primary rear main seal options include the Fel-Pro BS15868-1 (includes seal and plate gasket), and the Ford/International 1819733C91 kit, which often includes a wear sleeve to repair damaged crankshaft surfaces. These, generally made of FKM/Fluoroelastomer materials, fit the older IDI, not the 94.5+ 7.3L Powerstroke. Key Options & Considerations:
Fel-Pro BS15868-1: Common, reputable aftermarket choice covering 6.9L and 7.3L IDI engines.
OEM/International 1819733C91: Often preferred for durability, often bundled with a wear sleeve (often National Oil Seal #3893V included in kits).
Wear Sleeve (Repair Sleeve): If the crankshaft has a groove from the old seal, a kit with a wear sleeve is highly recommended to ensure a proper, long-lasting seal.
Installation: Requires removing the transmission and the rear seal housing plate.
Seal Type: These engines typically use a standard rubber or FKM rear main seal, not the PTFE type used in later engines, though high-quality FKM is crucial.
Ensure you are purchasing for the "IDI" (non-Powerstroke) engine, as the 1994.5-2003 Powerstroke uses a completely different, larger seal.
Thanks, it turns out the sleeve is only needed if there is major damage around that area. I hope mine doesn't need it. the viton seal that comes in the CDD kit is good to go. I plan on replacing the valve guide seals while im in there if it really is that much easier doing them with the engine out.
I'm not being disagreable, change the valve seals if you want, but I didn't on mine while it was apart, why? Because some ?long shield? ones, or 'better' valve stem seals can actually seal too well, your valves need a certain amount of oil, just not enough blowing by to burn blue smoke at idle, me, personally, because only, my engine doesnt burn much oil, and doesnt smoke at idle, I'm cool with a little more juice lubing down my valves, than possibly starving them with fresh virgin tite ones. .. But I would think you should make that call, and the correct shallow or smaller valve seals are almost certainly fine, if that's what you get in the kit, if yours burns oil or smokes at idle then yes 100 put, smaller, I would put ones on, bigger or tighter isnt always better with those one's unless your engine has issues, which it very might well have, depends, just my opinion, and thats all it is.
Only correction to the ai response on the gasket list, is the injection pump housing, there is not a gasket there, it should be sealed with good quality silicone or loctite 518, and dont do it, if you're not prepared to research how to disassemble and reassemble the gears correctly, and do make marks with a scratch awl.
I don't see any mention of "long shield" valve guide seals in that kit. I didn't see any such option when i got my kit. There are exhaust and intake which can't be mixed up, but no variate like that, that I'm aware of, nor would i use either. Just change to new factory stye fresh ones. I think I used a felpro set, but not near pc w/ records to check. If I'm missing it, my bad, but looks like just new replacement seals come with his kit.
I don't think I'd mess with the front cover either, if it's not leaking. I didn't when I replaced my engine, just the rear main seal w/ gasket for the plate. Such a cool design too, I like that. Both of these things, along w/ the oil cooler seals and gaskets are all 1/10th the job, w/ engine out.
Last edited by FORDF250HDXLT; Feb 9, 2026 at 09:19 AM.
Yeah, I heard the nightmares over the years enough to not even question that one, before engine went in. I noticed a big part of the issue, is that the headers allow you to get too close together. Out of the truck, it's easy to see and fix the lineup issue. In truck that could be hard to see. I prepped all for the turbo kit stuff to swap it over of course, but in that regard, I wouldn't purposely pull an engine to install one. They go in decent enough not to have too. No major advantage, though smashing in the firewall and a few other things would be a bit easier of course. Head gaskets, I wouldn't think twice. Pull her.
Next time I ever have to do another oil cooler, whether in the truck or pulled I'll get two all thread pieces the same as the cooler header bolts and screw one in a bolt hole on each side. Then you can dry fit it up once and then unhang it to install the gaskets. The two all thread will guide you in nicely and have the power to hold it up. I used short wooden dowels that fit well into a bolt hole each side to help me guide in the assembly. I didn't trust the dowels to hold up the cooler while I got in a couple bolts so had to help hold it up with one hand. All thread temporary studs would really help. Then remove them and install the last two bolts.
Next time I ever have to do another oil cooler, whether in the truck or pulled I'll get two all thread pieces the same as the cooler header bolts and screw one in a bolt hole on each side. Then you can dry fit it up once and then unhang it to install the gaskets. The two all thread will guide you in nicely and have the power to hold it up. I used short wooden dowels that fit well into a bolt hole each side to help me guide in the assembly. I didn't trust the dowels to hold up the cooler while I got in a couple bolts so had to help hold it up with one hand. All thread temporary studs would really help. Then remove them and install the last two bolts.
I wish I could picture what you're saying, as I've never done it before. Seems like good advice. Can you please elaborate and be more detailed?.
I wish I could picture what you're saying, as I've never done it before. Seems like good advice. Can you please elaborate and be more detailed?.
You don't have to understand a word he said because you're pulling the engine and with the engine out, it's a walk in the park. You wont have any troubles he's describing. It's wide open and fully accessible with engine out. Very easy bolt on part. No tricks required. The hardest part you'll have is pressing on the end caps with new o=rings. Nothing a floor jack and the truck bumper for a make shift press wont take care of. Little pressure, lots of grease and a lot of tapping with rubber hammer. Bolting back to engine is cake, while engine is out.
Last edited by FORDF250HDXLT; Feb 9, 2026 at 06:47 PM.
This is what AI says about pulling the engine. Anything to not,add or delete ( I have an automatic trans).
Phase 1: Clear the Front & Drain Fluids
Remove the Hood: Mark the hinge locations with a Sharpie first to make realignment easier later.
Drain Everything: Drain the coolant (radiator petcock) and the engine oil.
Front Clip Removal: To make life easier, remove the grille, headlights, and the upper radiator core support.
Cooling Stack: Remove the radiator, fan shroud, and—if equipped—the intercooler.
Note: If you have A/C, you can often unbolt the compressor and set it aside on the fender without breaking the lines, saving you a recharge fee.
Phase 2: Disconnect Support Systems
Electrical: Disconnect the batteries. Unplug the main engine harness (the big square connector near the driver-side valve cover). Disconnect the glow plug controller and the starter wires.
Fuel Lines: Disconnect the fuel supply and return lines. Cap them to prevent diesel from leaking everywhere.
Throttle Linkage: Disconnect the throttle cable from the injection pump.
Power Steering: Unbolt the pump and bungee-cord it to the frame to avoid opening the hydraulic lines.
Phase 3: Separating the Drivetrain
Exhaust: Unbolt the Y-pipe from the exhaust manifolds. These bolts are notorious for snapping; soak them in PB Blaster 24 hours in advance.
Transmission Bolts: * Automatic: Remove the inspection cover and unbolt the torque converter from the flexplate (rotate the engine by hand to reach all of them).
Manual: You’ll just be pulling the engine off the input shaft.
Bellhousing: Remove the bolts securing the engine to the transmission. You’ll need a long extension and a swivel to reach the top bolts.
Motor Mounts: Remove the nuts from the bottom of the motor mounts (accessible from under the crossmember).
Phase 4: The Pull
Rigging: Use the factory lift eyes (one front-left, one rear-right). Use a load leveler; it is almost impossible to clear the oil pan over the crossmember without tilting the engine.
The "Slow Lift": Slowly take up the slack. Ensure the transmission is supported by a jack.
Wiggle and Tilt: Pull the engine forward until it clears the transmission input shaft/torque converter, then tilt the front up sharply to clear the front crossmember.
Definitely will be easier to install the cooler with the engine pulled. But I think I'd still use the all thread to make it even easier. Takes no time what so ever to finger in a few temporary guide studs. YMMV of course.
I havent pulled an Idi, but plenty of other motors, so someone else probably knows, but I always leave the trans on the motor,
one less thing to take apart, and it helps the angle, and to guide it back in, but this might be too big a combo to pull up and out together idk.
?Would the Oil cooler interfere with lifting it out, if you just unbolted the exhaust mani and left em in place connected to the y pipe?
I always hate fighting exhaust studs, and many break even on a torch. That and motor mounts lining back up. ..
"You're plate rec is assuming I upgrade to electric right? Is there anything wrong with thermostats from today that led you to use that old one?"
Yep, don't ever bother with them damn mechanical pumps anymore, mechanical pumps used to be fine, once upon a time,
but some ask hat cornered the market, bought all the different brand's, and every one of em is the same trash pump with a different label,
spend 15 or 70, it's the same pump, and they're garbage unfortunately. ..
Same story with the thermostats,
most dont even fit or work right from the box.
I bought a motorcraft right from the dealership 10 years ago, and it was just a name box with a ***** thermostat, even dealer parts are suspect to bait and switch now a days,
I got burned, then I got a 39 year old therm, and it's perfect, rock solid, just like brand new.
Old doesn't mean bad, it's not wearin out, it's still new, just sits in a box waiting for you, new ***** sucks!
Thanks for the all thread tip on that oil cooler !
I'll be sure to remember whenever I have to attend to it. That sounds like the way to do it there !!
I've never pulled an IDI. I hear it's easiest pulling it straight out by disassembling the front end vs. over the front end.
Once you get the engine on an engine stand make sure you remove the heads before you try to rotate the engine around to service the oil cooler. I bent my engine stand bar trying to rotate it with the 7.3l I have on it.
Those instructions have you pulling the headlights and core support. That's many, many extra needless hours UNLESS your lift wont go high enough.
The engines are very heavy. 1k +. Don't pluck the trans with it, unless you have a very, very ,very hd crane and lots, and lots of help. You'd proably NEED to pluck the whole front clip off too. Way more work. You'll separate them to change rear main seal anyway, so just leave trans in truck, like I did.
By the way, be sure to get and change the front trans converter seal. You'll be right there too. Get an updated viton. You can change the tail shaft one anytime, by pulling the driveshaft. Change the front one now, because the trans or engine needs to be pulled to change it. Preventative maintenance, just like the rear main; catching them before failure, while it's easy.
Don't fuss about the oil cooler. It's EASY job w/ engine out. Silly easy. If you run into trouble, take whole works to machine shop and tell them you need the headers pressed on. Tell them to tap lots, while pressing and they'll be 5 mins max for you. To line it up to block, you'll fine you'll need to wiggle headers apart slightly. Apply some ultra black to gaskets and snug it down. All there is to it.
if you need more lift from cherry picker, let the air out of front tires, but watch you don't trap cherry picker legs so you can still slide engine out. It was a fine line with my f450. Your truck no doubt sits lower.
The rest of the list looks ok. Use it as a guide only, cheat where you can, where it looks worth it, pull whatever looks like it would be a pain if left and just work it out and back in, following what you see as you go, is really all there is to it. You can see what needs to be removed from engine/bay to disconnect, or for clearance.
Last edited by FORDF250HDXLT; Feb 10, 2026 at 09:22 AM.
Those instructions have you pulling the headlights and core support. That's many, many extra needless hours UNLESS your lift wont go high enough.
The engines are very heavy. 1k +. Don't pluck the trans with it, unless you have a very, very ,very hd crane and lots, and lots of help. You'd proably NEED to pluck the whole front clip off too. Way more work. You'll separate them to change rear main seal anyway, so just leave trans in truck, like I did.
By the way, be sure to get and change the front trans converter seal. You'll be right there too. Get an updated viton. You can change the tail shaft one anytime, by pulling the driveshaft. Change the front one now, because the trans or engine needs to be pulled to change it. Preventative maintenance, just like the rear main; catching them before failure, while it's easy.
Don't fuss about the oil cooler. It's EASY job w/ engine out. Silly easy. If you run into trouble, take whole works to machine shop and tell them you need the headers pressed on. Tell them to tap lots, while pressing and they'll be 5 mins max for you. To line it up to block, you'll fine you'll need to wiggle headers apart slightly. Apply some ultra black to gaskets and snug it down. All there is to it.
if you need more lift from cherry picker, let the air out of front tires, but watch you don't trap cherry picker legs so you can still slide engine out. It was a fine line with my f450. Your truck no doubt sits lower.
The rest of the list looks ok. Use it as a guide only, cheat where you can, where it looks worth it, pull whatever looks like it would be a pain if left and just work it out and back in, following what you see as you go, is really all there is to it. You can see what needs to be removed from engine/bay to disconnect, or for clearance.
