Scary Incident - Glitch or Pilot Error?

[CPJS]

....and your qualifications are

probably the same as most yours and most folks here.

 

[MaDPRoFF]

Cant see stop starts happening soon on a bike, as emissions are regulated differently, and more so a good rider should pretty well never stop

 

[tanneman]

I had never heard of that method, and it certainly isn't used with my diesel car, and I'm pretty sure it isn't used with my wife's petrol car either as the starter can be heard to operate. I think the vast majority of these systems simply user the starter motor as normal, though apparently Mazda have a system whereby a controlled and optimised stop position of the engine is used to assist starting, though the starter motor is still used, but for a shorter period than normal.

On a multi cylinder engines the chances are that one of the pistons will be on compression or just past TDC on either inlet or power stroke. The rest is bollocks because the spark fires just before TDC and allowance has to be made for valve overlap.

 

[tanneman]

Stop/start does not use the battery/starter. The engine is stopped with one piston at a few deg past TDC and then started by firing the ignition and away she goes. If the engine stands idle for too long a period the engine fires up before to much compression is lost.

Interesting, which manufacturer uses this method? And how is the cylinder pressure measured? As I understand starters and alternators are now a combined design and the move to 24V electrics for cars is coming. The reason the engine starts back up is to preserve battery power or if the engine is cold. The condition of the battery is monitored among other things and the stop start disabled as necessary to keep the battery charged.

 

[fred_jb]

Interesting, which manufacturer uses this method? And how is the cylinder pressure measured? As I understand starters and alternators are now a combined design and the move to 24V electrics for cars is coming. The reason the engine starts back up is to preserve battery power or if the engine is cold. The condition of the battery is monitored among other things and the stop start disabled as necessary to keep the battery charged.

I guess if the engine is stopped in a known position as per the Mazda system you can inject a bit of fuel into the cylinder with the best positioned piston and ignite it with a spark. This is not going to be an optimum burn as when the engine is running properly, but I guess it will produce a bit of shove and so assist the starter motor to get the engine spinning quicker. Of course this is a bit of a non-starter (pun intended) for a diesel engine where there is no spark ignition available ....