Hey everyone, I'm new to the Diesel & Ford world for about a month or so now and I was hoping for some ideas / insight.

I currently have a 88 F-250 with a 7.3 IDI w/turbo and an S5-42 Trans. I'm thinking about tearing everything apart here as the engine & trans needs huge help as well as a huge cleaning and painting underneath the body and throughout the frame. From what I've seen it's practically rust-free but of course, I'll see how true that is once I tear into it. Once I tear into the frame and body, the trans will have to be rebuilt as it wizzes in every gear on deacceleration and about half the time trying to accelerate. The Engine also has a big air intrusion issue, all the glow plugs are dead, runs at about 3.5mpg without any smoke, leaks, or performance issues (No idea how), has an oil leak above the starter as well as from the rear main seal, seems to also have a charging problem as it's constantly nearly dead and it's a pain in the *** to start and have to jump it every time. Overall ran well once started (before the plugs completely went) but it's completely soaked in oil and isn't functional at all to run, it'll need a big overhaul.

What I'm unsure about is if I should try to bring the 7.3 IDI back to life and improved upon with whatever performance parts I can get/mod, and same goes with the trans, or if I should go with an engine swap for better mpg and possibly hp. I'm just not sure if it's better to spend the money to bring the 7.3 to the same point I could be at for a base result with an engine swap. Any suggestions or thoughts are more than welcome!
Thanks in advance (:

 

first off I hope that is not the Turbo'ed 7.3 you are speaking of. because someone Stole yer Turbo....

that 5 speed Tranny should be giving you some pretty good mileage 3.5 mpg is extremely bad ...are you sure it is not Leaking the fuel out ?

I think the first thing would be to at least do a Compression Test .... cylinder leak down test would tell you more.. but just a simple compression test should give you an Idea of the overall condition.

 

Haha my bad, that pic is actually hiding it perfectly behind the top cover.

I'm surprised too about the gas, I've even cleaned the driveway underneath and let it sit for a few days. The only drips left were ones from the front two oil leaks. Still haven't been able to find fuel leaks.

I was able to do a compression test on it, however, I cranked it about 10 as opposed to six. I'm hoping to go back and do the test again, cranking six times per cylinder but doing it 10 times got me with these numbers.
1 ~410
2 ~400
3 ~410
4 ~430
5 ~400
6 ~430
7 ~430
8 ~430

For me, I'd love to see this truck going again but it's been a summer vehicle from the previous owner so I'm hoping to keep it that way this year and work on it till winter's passed. I live where the winters suck and salt is everywhere comes wintertime.

 

If the motor has less than 350psi per cylinder, I would sell it and spend my money elsewhere, rebuilds aren't cheap, the project you want to do will likely swallow 5-10k before you're done with it, now that's better than a new truck price tag, but I see too many "projects" for sale that someone has already disassembled and then found out it wasn't worth it or just didn't have the dough and they have hell selling it not to mention generally take a big loss.

I would address the fuel system first, get the glowplugs working, stuff you need for it to start and run, then address how much you like it and how much sweat, love, cursewords and money you're willing to put into it. Forget about the fuel milage and oil leaks, unless it's pouring out. Get it reliable then address the rest.

If you don't like it, at least you have a running/driving truck that will bring something fair on the used market.

Edit: I was writing my reply when you posted your compression specs, look pretty sweet to me. That motor is a good candidate to rebuild because it isn't slap wore out, but it also has enough life left in it to give you plenty of more miles.

 

I agree on the compression numbers.. I wouldn't rebuild a few seals and valve cover gaskets will most likely fix it up as far as the leaks go....

I'm still not sure about a Turbo with an OEM NA air cleaner

but if you have one sitting back there maybe that is leaking... I do see the Glow Plug Controller is relocated to the fender well so that makes that a lot easier to test than when mounted on the back of the engine. But the CDR is not relocated.

 

That's a pretty straight Bricknose!

The compression numbers are good too. Fix your air intrusion and leaks and drive it!

 

The trans noise may also just be gear rollover due to a single mass flywheel conversion. Assuming all your synchronizers are good I wouldn't stress it. Generally when bearing and stuff start going and having lots of play it'll show up when shifting or pop out of certain gears

You could try changing the fluid, or even going to a different fluid. I've heard really good things about the redline stuff, I just went with generic 10w-30 full synthetic, it shifts alot smoother than it did when I got it.

Edit: Good thread here on fluids for zf5

https://www.ford-trucks.com/forums/452207-best-fluid-for-a-zf5-manual-transmission.html

 

Are you sure you did the math right? Even my worst IDI had at least 7 mpg.

How did you calculate the mpg? If you drove it for anything less than 2 or 3 full tanks of fuel, you can't rely the results.

 

Hey, sorry for the late reply! I get about an hour at the end of my day to look at forums / respond after work & projects (:

Those are some awesome ideas and I do thank you all for your input. I'm also liking the idea of feeling it out until I know for certain if I want to dive into something like that as you said DarkOverCast. I guess I've felt the need to do an engine rebuild as I then know the condition of it for sure. I'll likely go that route though and have it running then shortly. Maybe do some logging this winter to sell as I just fixed up my personal chainsaw this evening too haha.

I also didn't know that the Glow Plug controller was located in a different spot. It's for sure been a huge help diagnosing, I think I'd lose it a bit if it was mounted that far back lol. I'll also attach one of the few pics I have of the turbo in the back. Definitely makes no sense to me as it goes from a nasty short cold intake that's above the manifold, to the intake bowl, down and back up to a rubber corner tube, then to the turbo. I'm really hoping on fixing that too soon lol.

Thanks Olds64, It's actually pretty off as the last owner didn't mount the body lift on the corner and has no lower mount nut. Ended up stressing the body and cracked the cowl on the passenger side... Just needs a weld and a new mount but the whole front is lower on the left and it also increased the gap between the front fender and door.

That's interesting too about the Trans.. I have changed fluids about 4 days ago now and it did help a little bit. The last batch that was in there was completely dark and smelled like overly burnt ATF. I'm hoping that's all it is though. I'll likely try changing the Flywheel, Clutch, & Synchromesh most likely and see what it'll do and go from there. Thanks too for the fluid post!

Lastly, I think I did the math right but I could be wrong. I filled it about three times so far and each time I drive is about 13km and it takes about a 1/8th of my tank (~9L) but I've also used my winch quite a bit with pulling trees (Never had a winch this powerful lol) and it still sucks it like a mad man. But I have a list so far of things to check and go over once I can get my GP's ordered and installed.
Thanks again everyone for your posts and ideas!

 

Almost forgot the pics...

 

hmmmmmm.

Can you take a few pictures with your phone back where your turbo is connected?

 

Isn't that a CTS? (Canadian Turbo Systems)

I could have thought they were the ones that used the oem air cleaner..there was also one more oddball company out there that I'm trying to think of..

Definitely interesting and I would love to see more pictures of this!

Edit found this video: https://youtu.be/YAhKHR5F5xE

 

Ahhh CTS ... 1st time I have seen that one

https://www.ford-trucks.com/forums/1...cts-turbo.html

 

That's an oddball turbo. I hadn't even head of it until now.

 

Hey it's Canadian ... lots of things are different on their Vehicles.

I have a buddy up in the Peg and I have sent him parts from my local junque yards and he had to do minor mods to make em fit windshield wiper parts for example are much more robust on Canadian vehicles than those used in USA