I got my 7.3 pulled and on the stand to replace the gaskets when i pulled the heads to replace the head gaskets I found this.







All eight pistons cracked and cracks between the valve in both heads. So looks like I need a new engine and the only thing I can find is a 6.9 im going to go look at this first thing in the morning 6.9 idi diesel motor what do you guys think? Is there anything I should look out for, what do you think its worth? I think 700 way too much if i cant see it run.

 

Aw bummer! I dunno, I would think a running diesel for $700 is a good deal, personally. But I'm not much of a negotiator. Probably could part out some goodies from the 7.3 to offset it a bit. Especially if you hawk the turbo...

As to buying an unknown engine, it depends on the seller. Scumbags will try and sell junk, but chances are a wrecked truck probably had a running engine before it was wrecked. Gonna just have to make an assessment.

If you pull the oil pan you will probably have a good idea if the thing ran out of oil- the rear two rods would be sloppy. Milkshake oil is hard to completely hide from a peek under the oil pan too. And you can see the pistons, and to some extent, the bores as well. Engines like these (diesels) tend to break rather than wear out though. IE is it broken?

Just took another look at that posting on CL. The low miles is REALLY suspicious IMO. I'd be a lot more comfortable buying an engine with 100k miles on it than one some random just had torn apart. Did some ding dong screw up the rebuild? Was it some pile of garbage mass produced crate motor with associated el-cheapo parts? Be careful you aren't buying some Idiot's screw-up attempt at an overhaul. Orrrr, it could be a freshly broken in Motorcraft longblock for a song...

 

Got a little toasty id say.

 

To be honest buying a used engine makes me really nervous. I haven't had any luck finding any others for sale around here, I wish they were easy to find I'm probably going to pass on this one.

 

I would consider looking at junkheap complete trucks while engine shopping. More work, and perhaps more money, but more of a guarantee that the engine isn't someone else's problem going away.

On most diesel engines in light vehicles the hard parts just don't see the duty to have any significant wear, so it's just a matter of seals or "abuse". The only difficult seals to do are the valve seals, which aren't critical anyway.

Don't be afraid of used engines, be afraid of crooks.

Look on CL in cars/trucks and set max price at $1500 and a bunch of stuff comes up for ford diesel- some are even misclassified engines for sale.

There's junkyard pull outs too. They may set you back more, but it's common to offer a guarantee- which has some value compared to a Craigslist promise.

I'd be considering a dead engine with different problems- like a bent rod or broken crank or the like. Someone's "core" might just need a couple valves from your old engine or something like that.

 

I went and looked at the 6.9 and its was a early block and there was no way it was ever rebuilt. It was covered with grime and rust, it also didn't have any injectors in it so I ended up passing on it. I found a good 7.3 that a salvage yard had shrink wrapped on a pallet with a warranty.

 

find some heads and put pistons in it.

 

Are you guys seeing something in those pics that I'm not? I see a little line (crack) in the one piston... Nothing in the heads.

 

I know this is an old thread, but for what it's worth others may benefit from my comment.

Even if you run a diesel out of the truck, you may have issues like cavitation damage, head damage, head gasket damage, oil cooler damage that will not appear until you pressurize the cooling system. So it is still a toss up unless the seller can guarantee the engine.

 

I'm curious: Of the pictures shown in the first post, what is actually critical and what is mostly cosmetic?
To me, I'm seeing a small crack in the middle of the piston, but it doesn't look huge or deep. Could you just /run/ the darn thing until it breaks worse?
Same with some of the other cracks and issues... I couldn't tell from the head pictures, but would it run OK in the current condition, or would it actually be leaking through those cracks?

 

The crack between the valve seats is important. the crack in the piston is important. Cracks in the pre-cups are not important up to a point.I have built 2 of these and I can't get one together for under $1500.00 and the only labor is the vatting and decking of the block. So use that as a guide these are not cheap engines to work on.

 

The cracked piston would likely pass gasses and creating a blowby type issue, although it should exhibit a greater discoloration that is difficult to clean. The walls of the cylinder look good with no apparent ridge which makes it perfect for rebuilding. Chances are, if cracked, it extends deeper down toward the rings. Any crack could get worse and become catastrophic. If one piston is cracked it would be wise to pull all of them for inspection.

 

Sure that's a crack?

 

I wonder if this is why the 6.9l in my truck runs so bad.. what symptoms/problems was this engine having?

I was looking at used engines.. ended up spending more on a reman with a warranty.. I couldn't see spending $1500+ on a used engine that might crap the bed in 100 miles...

 

How much was a remanufactured unit?