Having a problem with a 1985 mercruiser 140HP with volvo 4 cylinder engine and 2 barrel carb. Carb has a tag with the numbers:1389-8490. It runs great for the first 30 minutes or so. After that it idles rough. If you shut it off, it floods when you try to restart. Once you get it started, it often dies when put in gear. After you get it in gear and moving, it runs fine at all speeds above idle.<br /><br />Automatic choke appears to be working fine meaning it opens up after engine has run for a few minutes. I thought the float may have had a hole in it but checked and it is OK. Idle speed appears about right. My experience with carbs is minimal. I'm at a loss. Any help appreciated.