[RandyP]

The 84 school truck I bought, it had been sitting for like 4 years. I put marvel mystery oil down each spark plug hole and let it sit for a day, poured some gas in it (was empty) with some marvel mystery oil and it fired right up for me.

Of course then it was obvious the valve cover gaskets were gone, gas lines were fairly rotten, most vacuum lines were very brittle and the brakes had issues. It was at that point I just sold it.

I will say this, I put some seafoam down the vacuum line from the brake booster to the intake in my 79 K5 today. It had been sitting since 2006 when I bought it a few weeks ago. It amazingly had fired right up for the PO after sitting that long, and I drove it 1 mile to my shop. It ran very rough though. I wanted to change the plugs but was told to do the seafoam thing first, and some B12 carb cleaner after that. You talk about one helluva smoke show, but I'll be damned if it did not make that thing start purring. I can not wait to get the new plugs in it now, I bet it will make that tired old 400 have a breath of fresh air to it.