Bus Drops from 55 Mph to 45 Mph and back, huh?
Just bought a 1985 International 9 liter diesel. Test drove it and it ran fine, got up to 60 Mph. However, after buying the bus and driving it home it seemed sluggish. It got up to 55 Mph for awhile but would then drop to 45 Mph. After 10 mins or so it would get back up to 55 Mph then drop down again. The bus had sat for over a year, perhaps there's algae in the diesel that's clogging the filters. I put 15 fresh gallons of #2 diesel before driving it home. Any thoughts? Also the battery is about toast, but don't think that has anything to do with acceleration, only cranking the engine over. Thanks.