Not only is this possible, but it’s almost certainly what happened. If the “piston is pretty tore up” as it says in the OP, then something clanged around in there. Either the shop dropped something into the spark plug hole when putting the new plug in (highly unlikely), or a part of the plug or threads banged around in there.
those plugs had 150k on them.
The gas can be siphoned out of the tank.
Goto
to find a value for the van. At first glance the private party sale price looks like it is about $1470 for 150K miles–which suggest that selling it on Craiglist or to a junkyard and getting another used van is probably as good as anything else.
OK we are now at the root of the problem.
The plugs on a Ford V8 have a change interval of either 90,000 or 100,000 miles.
You did not do the required maintenance and you had a spark plug grenade at 150,000 miles.
If the top of the piston is damaged, and the engine is blowing blue smoke, it is 99.9999999% for sure it is from shrapnel left in the cylinder by the grenading spark plug.
It cannot be from a helicoil installation, the cylinder heads are aluminum and any chips that might have fallen into the cylinder would either burn during the first power stroke in that cylinder or blow out the exhaust valve on the first exhaust stroke. The idea that a piece of aluminum swarf scratched the cast iron cylinder walls of the engine is well silly. Even if it did, there is no way to get blue smoke from the tiny scratch that might be left.
If you were to have a tear down done, you will find one or more of the following conditions:
[ul]
[li]There is a hole in the top of the piston[/li][li]The rings were severely damaged from the shrapnel[/li][li]The cylinder walls have a serious grove from the shrapnel[/li][/ul]
The rough running indicates that this is now a V-7 engine and there is a lack of compression in that cylinder.
If the van were in my shop, I would want to replace the engine whole, as most likely it will need a a short block and head minimum, and you will want to do a valve job on the other head, so you might was well get a long block (compete engine)
Or
Buy a used junk yard engine and have it installed.
All because you didn’t do the required maintenance.
I hope you invested the money saved on the maintenance you didn’t do well, you are going to need a bunch.
Good lord, Detroit is still producing vehicles which self-destruct at 100,000?
Do they still use 5-digit odometers?
Ford has been building V8’s since the early 1930’s. How is this acceptable?
No they build an engine that requires new spark plugs at 100,000 miles.
It’s when the owner doesn’t replace them one of the plugs fails at 150,000 miles.
Not Ford’s fault.
I am a dope. I bought the van in May with 150k on it. I thot about replacing the plugs and wires but…procrastinated. A bitter lesson indeed. I’ll carry on. It could be worse.