"If you do any bottom end engine work with head work, the cost will exceed the cost of a fine used engine."

That's the kicker, right there. It surely needs a head gasket. The head *may* be so warped it can't be saved. I've seen a pretty bad '92 740T get saved before, and it always ran reliably- but they took almost 60-thou off the head. That's a sixteenth of an inch, an awful lot of aluminum! Too much in my opinion. And as for the lower end- it had tremendous piston slap, in spite of having good compression numbers. They were within 10psi. Turned out, later, when the owner couldn't stand the slap anymore and the engine was replaced with a healthier 70000 mile block, the #1 piston had actually started to melt. Don't ask me why the cylinder wasn't scored and the thing still had compression- there wasn't a good reason for it.

In the end, fixing both the top end, and bottom end of this engine is going to cost more than simply pulling it, finding a good used one, and calling it a day.

And yes, you shouldn't trust a flaky temp gauge. It's telling you something, even when it doesn't work!

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Rob Bareiss, New London CT ::: '87 244DL/M47- 229K, 88 744GLE- 218K, 82 245T-181K Also responsible for the care and feeding of: 88 745GLE, 231K, 87 244DL, 239K, 88 245DL, 246K