A few weeks ago (November) I posted about a project 740T that had a total valve stem seizure due to aged reformulated gas.

I had the machine shop go over the head, then reinstalled it with all new gaskets, seals, etc. It ran beautifully. Excellent power, tight ride. The thing only has 85k or so.

Well, it sat for a few more weeks, and then was driven around again. Not much, maybe 5-10 miles in the last two days. Total mileage since rebuild maybe 20 miles.

Also, I had added a lot of fresh premium gas to the almost-empty tank to dilute the old stuff, if there was any left.

Well guess what I had to go and tow back today? The same car. The timing belt mysteriously slipped/broke/whatever. I thought I might've spaced something when I was stitching it back up last time. Subsequent investigation showed that the #2 intake valve had seized AGAIN. After pulling the valve cover, camshaft, and intake manifold, we were able to get the thing loosened with doses of PB Blaster and carb cleaner on the valve stem. And copious taps with a soft mallet combination.

The other valves were coated completely with brown molasses stuff, but were free in their guides. I sprayed them with penetrant too, just as a protective measure.

Obviously there is something in the gas tank of this car. Either the reformulated gas has deposited some jelly in the bottom of the tank, or someone dropped something in there. I doubt it's sugar, as the intake/injectors would've fouled, and the pistons would have been coated. They're totally clean.

Tomorrow I'm opening up the tank to see what the deal is. I'm sick of seeing this engine, and this car. I'll post back with the results. If it's a gas issue, or a tank degradation issue it's of particular importance to anyone in a reformulated gas area.
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Chris Herbst, near Chicago, IL. 93 940, 91 240, 90 240, 88 740, 87 240