Mechanical Repairs & Troubleshooting On Diesel Engines, School Buses and Related Operating Systems.
Tuesday, August 28, 2007
A typical road test in a Thomas School Bus, this unit has a Cummins ISB Model [electronic] Diesel Engine and when roadtesting it's always best to find a good grade to find any faults with performance. Sometimes the transmission has to be considered if it's shifting poorly. If you're climbing a hill and the trans. upshifts too soon you'll start lugging the engine which feels like an engine power problem.
Hi Jim, This bus was shifting fine, it's an Allison electronic transmission 3000 series. I was just pointing out that checking out engine performance on a grade is the best way to detect problems. If the trans. is out of synch. with rpms then engine lugging happens which makes diagnosis harder. tks for the comment, John.
Does that video show a Thomas with a problem or did it shift fine. I can't tell from the audio. Thanks.
ReplyDeleteHi Jim,
ReplyDeleteThis bus was shifting fine, it's an Allison electronic transmission 3000 series. I was just pointing out that checking out engine performance on a grade is the best way to detect problems. If the trans. is out of synch. with rpms then engine lugging happens which makes diagnosis harder.
tks for the comment, John.