Usually if there is a power valve problem it will not idle very well and it will run extremely rich. the power valve should be a 2.5. Since you just recently rebuilt the carb you may have squirreled out the power valve gasket which will dump gas pass the power valve. Check your oil and make sure you are not dumping fuel into your crankcase. You can pull off the front fuel bowl and check the gasket behind the power valve. You also need to check your float adjustment in the front fuel bowl. Which is probably the problem since like I mentioned earlier a power valve problem creates an idleing problem.
1987 TriStar 190 Red & White
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