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A few years back I bought a 79 Silverado with the 5.7 Diesel. It ran well and had several upgrades to help with reliability through the years. I enjoyed it, although 60 mph was a tall order for the truck it would eventually get there, it was amazingly good on fuel!

Now my square body collection is all gassers,but I'd like to find clean pickup with the 6.2
 

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I drove one of those that was actually working... I believe it was 1984.
The change in the number of cylinders operating was imperceptible.
IIRC, the only sign that was something was going on was a display on the digital dash.

It was in a beautiful white Eldo with red leather.
If I knew what I know now, I would bought it... disabling 8-6-4 is very, very simple.
Then you have an iron block 368.
My parents never had an issue with their Coupe de Ville V8-6-4. The indicator was on the lower center console, next to the climate controls. They eventually traded it in on a 1987 Brougham D'Elegance.
 

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I own 3 Diesel Buick Rivieras!
My Olds Toronado diesel I reluctantly traded in when I bought a new car, I didn’t have anywhere to store a second car at the time. I remember when leaving the dealership there were 4 mechanics, a couple salesman and the owner of the dealership with the hood open, engine running and they asked me how I did it and kept it running. The Toronado had 468,000 miles on it and the only engine work I had done was as soon as I bought it (it had 78,000 miles in it) I studded the engine with ARP Studs and upgraded the head gasket to a Victor Reins gasket. Of course I replace the water pump several times, new radiator twice, several starters and the usual items.
I was and still am religious with changing oil every 3500 miles, I’ve used only Kendal D3 straight 30, (10w-30 in winter when I was up north).
I studded all the Rivieras’ engines and have never had any head issues at all.
They were actually good engines but at the time the dealership mechanics had never worked on diesel, poor to nearly no training on them and the no water separator was a big issue coupled with owners that didn’t understand diesel do’s and don’ts. By the time GM corrected they weak head bolt issues, water in fuel light and making sure ALL head bolts were replaced when there was a blown head gasket issue bs just replacing the broken bolt and the improved head bolts resolved most all issues, however damage was done.
If you maintain oil changes, premium diesel fuel and Stanadyne fuel conditioner you can get years if reliable performance. It’s also important to realize they were made for speed the were made for fuel economy and to get to the CAFE standards of the time.
The other myth that they were converted gas engines was flat out just that a MYTH.
The did share the same stroke, bolt pattern, displacement as the gas counter parts but it stopped there.
The block was heavier due to the addition heavier metals to strengthen the block, thicker connecting rods, floating wrist pins. The crankshaft were 3” in diameter vs 2 1/2” in the the gas. It had the valley for the gear driven injection pump, stronger heads, injector and glow plug holes in head, the stainless steel pre-combustion chamber, valve reliefs in the pistons(as the deck out), the webbing was thicker and the block was solid around pistons due to the increased pressures, having a 22.5:1 compression ratio vs 8:1 in the gas. The list goes on.
But if you changed the oil, used good fuel the engine will last a very long time.
None of my engine have blowby, burn excessive oil or leak oil.
And 32 mpg on the freeway isn’t hard to take in a 350 V8 5.7L engine and a 2 ton car!!!
 

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OMG I finally get to post something, why is replying on this board so hard?!? Just comes up blank with no where to put words....

I have just recently came into a 1983 cutlass ciera brougham with a 4.3 ltr LT7 diesel. The odometer says 98,000. It had sat for around 17 years(according to previous owner) before I came into it trying to dive deep head first into diesels having no prior knowledge of them, looking to turn it into a veggie car. I traded an old mower for it so i'm not out much. At least that is what I believe it is, then again the odometer only has 5 digits, 6 if you include the tenth mile so maybe it is realistically 198,000 but unlikely seeing as how the brake pedal is fairly new looking with few rips or tears on the seats, the car has the multi flag emblem which were only on the international series, which were supposedly only produced from 1988 up but my 1983? has it. So in retro spec I have no damned idea what I really have. I know it does run a little rough on start up and spits and sputters gray/white/blue? smoke at first but clears up once warm and runs better until you put the gas pedal to anything over half pedal it starts spitting and sputtering again but is getting better the more fuel I run through it. Aside from the leaking rear break seal it is golden, I am trying to just cap the rear drum brakes at the master cylinder so I can at least use the front brakes without the pedal going to the floor, sounds easier than it really is apparently getting the right sized plug with the right pitch is real complicated. The guy had just recently put a new battery in it and rebuilt the transmission a couple of years ago(according to him) and eventually just gave up on it. I am trying to figure out what codes it is throwing threw the computer and just recently tore the dash cluster apart trying to figure out why the service engine soon light didn't work just to discover they never intended for it to have a light there according to the cluster panel plug, so my question is how do I pull codes from an OBD 1? with out a reader or service engine soon light? I checked the OBD port under the dash board, in middle under ash tray!, and it only had two terminals..... Any help with this much appreciated.
 

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The OBD port was more for the assembly line
The smoke on start up, I’d check all glow plugs to make sure the are working and then the plow plug controller which was electronic on that engine VS the thermal style on the 5.7l. There is a tempature switch that feeds the controller and a “diesel diode” which is normally on the fender tower.
The “CEL” light (Check Engine Light) on the dash does and should work. There is a check list for when it comes on, how long it comes on as well as if it goes out above certain RPM’s.
The throttle issue could be one of several:
-dirty filter
-fuel pump going bad
-EGR valve stuck or not working correctly
-IP issue internal
-Injection timing off, it should be -6 degree TDC
-bad or sticking injector(s)
-the vacuum throttle position sensor on the side of the IP, if it is a California Emissions car it won’t have that but a MVS on the injection pump (which is a potentiometer)
Well I hope that helps
 

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Not to revive a dead post but more then a fair share of folks do!

I am just turning 42 and these were the FIRST Diesel engine’s I was trained to work on.

In the last year I have went from zero to the following list acquired :

1985 Buick Electra park avenue fwd 4.3l v6 diesel
1983 custom cruiser 5.7l diesel ( majorly rusty car removing engine.)
1981 Cadillac Eldorado 5.7l diesel
1980 Cadillac deville 5.7l diesel
1980 5.7l pencil injection engine 30k miles spare
1980 poppet engine spare (locked up from sitting outside)

Working on getting the following:
1985 Oldsmobile 98 regency FWD with Voice system !! Yes the kind of car that talks! (Aka your face is ajar lol )

26 foot load of spare 5.7l parts and a spare 6.2l engine

Multiple 4.3 motors also possible .

if anyone has parts they want gone or to sell message me please!
 
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