Are these engines reliable? Parts available? Any drawbacks from this engine any input would be appreciated thx

 

That engine is very reliable. The old glowplug controller is not, so you might need to do something about that if it hasn't been addressed already.

The 6.9 and the 7.3 idi diesels are non-turbo from the factory (except early 94 models) so they don't have a lot of power. And you can't "turn them up" and chip them like the newer diesels. They do make turbo kits to add to them, and that ups the power nicely.

 

I just bought my 1986 F250 with a 6.9L IDI. I've thoroughly enjoyed driving it, even though it is sort of anemic without the turbo. The glowplug controller and air intrusion through the water separator have been little annoying problems I've had to deal with, but any vehicle has trouble areas. I would much rather deal with those issues than overheating and blown head gaskets on a 6.0L PS.

 

The great thing about the old diesels are the lack of wires. All those wires are good for power, but when something breaks watch your wallet get a lot thinner.

 

I use credit cards for everything, so my wallet stays the same thickness no matter how much I spend.

 

That seems to be the way the world works these days. I try to live without borrowing money. Of course I do not have a lot of the nice modern things that other people have either. But once I figure how much the bank is getting out of all this, that drives me to try and not borrow and pay my card off each month.

 

i have my first retro-drivver, an 85 diesel.4spd 2wd. yea, its ok. i like having to fuel only once a week as the mpg is strong in these rigs.

that 4x4 you will have , can be a basket of headaches.

i like my 6.9.

 

+1; pay the full balance every month, and it's no longer really a "credit" card, but a "secure payment" card.

 

x2


Sometimes I wonder if it's better to be more like my brother-in-law though. My mother always said he is a "free spirit." Which is actually a nice way of saying he doesn't have a J-O-B.


Sorry...

 

I am the original owner of an 86 F-250 with the 6.9l diesel. I love my truck!

I made a few modifications. I disconnected the fuel water separator. The fuel filter can hold a lot of water. This was done 20 years ago and no problems with the bypass.

I installed the Banks Power Pack which included the high rise air filter and a larger diameter exhaust. Improved the power significantly.

I also disconnected the glow plug controller and added a manual glow plug push button under the dash just under the glow plug indicator. It's a starter button switch. Push it in when the engine is cold for 6 seconds before cranking it up. If the engine is warm you don't activate the glow plugs. If the engine is somewhere between cold and operating temperature you can use less than 6 seconds of glow plug. I made this change after the controller turned on the glow plugs on the freeway at normal engine temperatures and fried the glow plug set. I recommend making this modification before you need to replace the glow plugs as they are not cheap and the momentary button is about $10 bucks.

Other than these mods the truck is stock.

Good luck with your 6.9!
Big Blue 2

 

I agree with not borrowing money, certainly not for luxuries. You are mistaken on credit cards though. My primary credit card company gives me a 2% discount on every purchase I would have made anyway via 2% cash back. Purchases on Amazon (good source for some automotive parts) I get a 5% discount by using a different card.

I haven't paid a bank directly for use of a credit card in over a decade. Keep in mind there are transaction fees for using credit cards (currently 1.4%-3.5%, sometimes plus a very small fixed cost per transaction), any store that doesn't offer a lower cash price has included that cost in the price of everything they sell. By using a card you recoup at least part of that transaction cost that you pay for in every purchase.

 

Very reliable engines and plenty of parts availability. The only exception would be 93-94 factory turbo engines which no one makes pistons for anymore. There are alternatives though.

Common failures on 6.9 engines are head gaskets, normally leaking oil or coolant at the rear corners of the gasket rather than a fire ring failure (i.e. do it at your leisure). 6.9 has smaller 7/16" head bolts. Studs are available that remedy the weak clamping force of factory small bolts and are fine for any of the "stock" turbo options.

The early 6.9 blocks had an issue cracking around the block heater if that was used. That changed I think at some point in '84, there is a document floating around with year and serial number of various changes to the IDI. The early 6.9 also had press in piston cooling jets rather than bolt on. This can be problematic when rebuilding the engine as they are NLA and must be very carefully removed and reinstalled in the proper position, there can be issues with them not being a tight press fit. I think this changed in '86 or '87 to bolt on jets.

Turbo options are available new from Banks, Hypermax, and R&D IDI Performance. Higher output injection pumps and improved injectors are available from R&D IDI Performance as well as Conestoga Diesel Injection. To make one of these trucks perform acceptably you will need a turbo and a higher output pump. The stock pump can be turned up easily, but is only capable of so much.