RE: X9 | X10 - Acquisition of interdeck coaches from Oxford Bus Company
(26 Jul 2020, 10:55 pm)deanmachine wrote Probably due to the smaller engine, the B9s engine was very under stressed for its application, 260ps from a massive 9.6 litre engine, the same basic engine making 380ps in the B9R coaches just shows how under-stressed it was. A little 5 litre, same size you get in streetlites afterall, doing similar work to a 9 litre+ just gives more potential of going wrong, even if it’s fundamentally a good design, which I’m sure it is being a Volvo.
I'm not a mechanic, but If it was down to the engine being over stressed, I'd think it would be more of a catastrophic failure than what actually happens.
To me, if the engine is being over stressed on a motorway journey, that is down to the gearing rather than the engine, once a vehicle is on the go, it takes very little power to keep it moving. It's the constant stop-start that puts the most stress on an engine.