Are these engines worth their weight or what ??

 

I'd say they're more durable/reliable than the Powerstrokes. Other than problems due to poor maint. , they don't really have many problems. But, they don't have the power of the PSDs either.

 

I've got an 83 6.9 with an ats turbo, I think it is just as powerful and reliable as my father's 02 F350. My c6 is strong, but needs more gears.

 

What is an ATS turbo ??

Did Ford offer a turbo 6.9 in 1986 ??

 

The first year Ford offered a factory turbo was in 93. ATS is an aftermarket turbo like Banks.

 

ATS is also the company who built the factory installed system for Ford in 93/94 on the 7.3 IDI.
Anyhow, as for reliability and durability, these old engines are extremely reliable with proper maintenance, and still pretty reliable without it. About the only real issue other than air leaks in the fuel system is glow plugs not working.
And, since they're old, and nice and simple, parts are pretty cheap compared to the new engines... You can get a complete set of IDI injectors for what one 7.3 PSD one costs.

 

I'd say nearly bullet proof I've got one that was given to me, this guy knew nothing about diesels he thought the the compression was gone the tranny was bad. I knew what was wrong with it but I didn't tell him. new set of glow plugs two new batts. and the thing came right back to life after sitting for 6 years C6 tranny came to life also with some good oil

 

I have a 90 IDI and a 96 power stroke. The 90 is better. Easier to work on and more dependable.

 

I have a 89 F250 with a 7.3 diesel. After 276K miles I think it is just getting broken in. Other than replacing glow plugs and normal maint it is running like a top with a only a oil leak in the valve covers.

 

Before you go and put a hair dryer on the 6.9 make sure your head gaskets are in good shape you may even want to see if you can up grade the headbolts to studs from ARP.

The 7.3 IDIs have better head bolts but they suffer from cavitation so its one thing or the other.

The 6.9s also suffered from a bad GP system what most people do its make a push button GP system and use constant duty GPs.

As for IDIs yes they are good I would rather have a 7.3 IDI over the 6.9.

 

That is a little over 21,000 pounds as it sits in the picture.
It has done this kind of work for 20 years in the WV mountains.
I put a reman 7.3 turbo in it at 300,000 miles, only because the oil consumption was getting out of hand.

The first 7.3 blew up at 2,800 miles.
The second one made it to 9,700 miles.
The third one made it to 17,000 miles.

I just bought a salvage yard 6.9 to put back in it three hours ago.

 

Why do they keep blowing up ??

 

bought my 90 used now has 196000 mi on her seems to run fine . a month ago used her to move 5 loaded RR cars at work each weighing 231000 lbs +/- just let cluch out and idle away.

 

Dave is a little hard on his truck you should see some of the pictures of what he has hauled for loads on that truck

If you build the 6.9 right it should give you lots of service same with the 7.3 IDI. If you bought a rebuilt 7.3 IDI had all 8 cylinders sleeved you would never have to worry about cavitation again. If you wanted to spend more money find a set of turbo pistons and rods then a factory turbo you should be good to go.

 

Well the reman company does not have a clue on how to install sleeves is the main reason. I also am starting to think the 7.3 block can not take sleeves to well, when they cut out all the block to install the sleeves it is so thin it cracks.

The first engine had two sleeves that had dropped down into the block about an 1/8 inch on 1 and 3. It cracked the block between 6 and 8. The head gaskets were not installed properly, the head bolts punched new holes in the gaskets. Intake bolts were stripped out. Some of the head bolts were loose. About 1 pint of clean assembly oil drained off the head bolts onto the tray we laid them on when we removed the heads.

The second engine had a strange vibration from day one. It also made a very strange sound when we fired it up after installing the engine. It had a very high pitched rattle to it that hurt your ears inside the small shop. I also had oil pressure issues with it. Hot idle oil pressure was almost nothing. At 9700 miles the crank broke while driving down the road at 45 MPH empty.

Engine 3 cracked the block between 1 and 3. All the sleeves were below the deck of the block. Several of the sleeves were out of center so bad in the cylinder that it had scraped aluminum off the skirts of the pistons.

Bad or no quality control is why I think they keep blowing up.
That 6.9 hauled those loads for 20 years and 300,000 miles.
When I get the 6.9 back in it I bet she is gonna haul a lot more of them.
Don't everyone put 9200 pounds of rock on their 250?



PS maybe I should also say mine is not exactly a stock 1986 F250.
I have more springs than a 550 does from the factory.