I wanted to share with you our experience with unsiezing an engine in the hope that it might help someone with the same problem. Obviously there are many issues that can cause this, but here's what happened to us....

We (my cousin and I) bought a 1984 5.0l 5 speed manual from Ebay, which had been sitting for 5 years after the clutch went; we hadn't even seen it until it arrived on the transporter . It only cost £450 so we felt that we could sort out any issues and put it on the road; however after connecting the battery it became clear that the engine was siezed which wasn't mentioned during the sale. Additionally we tried a long bar on the crank, but it just wouldn't budge. We decided to remove the heads with a view to pounding on the cylinders however upon removal of the carb we found the inlet manifold flooded with water and spoonfuls of salt covered the walls. Recently we had floods in England so perhaps the car had been towed out of the river we thought and the pistons were corroded to the block?

To cut a long story short, we noticed an incredibly minute amount of movement on the alternator each time we flicked the key, so did this for about an hour or two moving the engine millimeter by millimeter assuming that the movement would remove any internal rust after a full revolution. After a couple of hours the engine turned very very slowly so we guessed that we were correct and the walls were rough. Out came the spark plugs and down each went a mix of oil and petrol. Luckily as soon as jumped back in the engine turned immediately very quickly and now fires without rattles or blue smoke.

So if you've bought a car that has been standing, perhaps give ring corrosion a thought and try as we have... it might work. And a last thought, now its running it siezes as it becomes warm, yes we forgot to replace the petrol laden old oil which is obviously bad at lubrication so we're about to do that and we should be good to go!!!!

 

I'll try to be happy for you, but I've been through this, and as they warn, "your results may vary" Over the next 500 miles my fuel economy fell off to 9 mpg on the interstate, and Before the 500 miles were up, driving from Reno, NV to just past Wendover, it was burning oil getting past the rings to the extent that I seized the engine, despite topping off the oil when I bought gas in Elko. There was a huge cloud behind me as I coasted to a stop. Oil was literally dripping from my tailpipes rear spoiler and rear bumper. This was in an '80 Firebird, back in 1999

 

Lol, fingers crossed then