Is it bad to turn the engine on and off frequently

**Vodka** · June 29th, 2018 11:34 PM

Originally Posted by yebo

I personally call it the Mig 15 philosophy. Why make something to last 10000 flying hours when it will get shot down after just 2 months? So the russians made the engines to last for just 100 hours, then made many hundreds of them.

sabi nga ni stalin: quantity has a quality all its own

**kisshmet** · June 29th, 2018 11:36 PM

Originally Posted by danegoesonline

Im a Grab Driver and after I drop the passenger off I am turning off the engine to save fuel consumption, after 5-10 minutes I will start it again. Is this ok? Am I shortening any parts of my car? Please help, I will appreciate it very much.

First observe your tachometer every time you start your car..note how high it goes (X rpm). Then observe your idle rpm (Y rpm).

Using ratio and proportion..X:Y you can deduce the number of minutes your idling engine matches the starting engines fuel consumption. 2000rpm:800rpm=2.5:1 ratio. To save fuel you need to anticipate the number of minutes you need to run idle and compare it to the ratio you get. If you will idle more than 2.5 minutes then you will save fuel by turning off your engine. If you will run idle in less than 2.5 minutes then you wont save fuel by turning off the engine because your car will gulp more fuel as you start your engine again

Every car has different oil so starting rpm is different on every car. So my ratio and proportion example could differ on each car you own. Thick oil are harder to start than thin oil so it would consume more fuel to start an engine

Now on what will be commonly affected component of your car if you frequently start an engine. Its the battery, thats why battery manufacturers cut the warranty period for commercial vehicles to just 6 months.

Sent from my GT-P3110 using Tsikot Forums mobile app

**dr. d** · June 30th, 2018 12:00 AM

Originally Posted by SoleusBB

I find it hard to accept that starter motors have gotten so fragile?

.

errr... what is the basis for the statement daw?

**dr. d** · June 30th, 2018 12:06 AM

Originally Posted by kisshmet

First observe your tachometer every time you start your car..note how high it goes (X rpm). Then observe your idle rpm (Y rpm).

Using ratio and proportion..X:Y you can deduce the number of minutes your idling engine matches the starting engines fuel consumption. 2000rpm:800rpm=2.5:1 ratio. To save fuel you need to anticipate the number of minutes you need to run idle and compare it to the ratio you get. If you will idle more than 2.5 minutes then you will save fuel by turning off your engine. If you will run idle in less than 2.5 minutes then you wont save fuel by turning off the engine because your car will gulp more fuel as you start your engine again

Every car has different oil so starting rpm is different on every car. So my ratio and proportion example could differ on each car you own. Thick oil are harder to start than thin oil so it would consume more fuel to start an engine

Now on what will be commonly affected component of your car if you frequently start an engine. Its the battery, thats why battery manufacturers cut the warranty period for commercial vehicles to just 6 months.

Sent from my GT-P3110 using Tsikot Forums mobile app

in my diesel innova, my cold starting idling rpm, is the normal temp idling rpm, is the initial few-seconds' idling rpm when started from hot.

i may have saved on gas, but i feel it made me replace my battery earlier.

i don't kill my engine anymore, during 1-2 minute red lights.

**DiliKoAmericano** · June 30th, 2018 12:07 AM

The last post doesnt make an ounce of sense to me.
(no offence intended)
Interesting comments about starter motors getting better and worse. I think theyre getting different, but not neccessarily better or worse.
One fact still remains, weaker batterys will expedite the death of a starter motor, and that is what my post was all about.

**dr. d** · June 30th, 2018 12:10 AM

weaker batteries won't expedite the death of starter motors.
on the contrary, starters will last longer, because they won't function because the battery ain't got no juice to make 'em function.

**Vodka** · June 30th, 2018 01:22 AM

well a weaker battery will have more voltage sag and will push out less amps. so the starter motor will end up operating at a bit lower voltage and amps i.e. it'll feel lethargic. so you may have to operate it a bit longer in order to start the engine

**oj88** · June 30th, 2018 09:35 AM

Originally Posted by dr. d

weaker batteries won't expedite the death of starter motors.
on the contrary, starters will last longer, because they won't function because the battery ain't got no juice to make 'em function.

I think what he meant was, with a weak battery, it may not have enough power to even turn the starter so it ends up burning the starter winding. It’s the same reason low coltage (ie. 110v) will kill your unprotected 220v appliances that uses a motor (ie. Old school ref and A/C).

On the topic, you can’t cheat physics. Frequent start-stops will definitely put a toll on the battery, starter, and related parts. By how much, will depend on the quality, tolerances, and design of the individual components. Internal to the manufacturer, these components all have MTBF and duty cycle figures which are not typically available to the public. The best thing to do is to use good judgment to balance between protecting the environment vs your vehicle and do the start-stop dance only when absolutely necessary.

**dr. d** · June 30th, 2018 09:58 AM

OT.
did you know, how VW factory workers used to move VW platforms in the factory?
they engage the starter.

**SoleusBB** · June 30th, 2018 10:28 AM

Originally Posted by dr. d

errr... what is the basis for the statement daw?

Morning guys. The statement was based on the insinuation that switching the engine on or off (under reasonable use) will eventually lead to failure of your starter motor. All I'm saying is hindi naman ganyan kadali masira ang starter, placed within the context of the thread starter's original post and intended action: the TS plans to switch off his engine in between rides, habang nakatunganga siya for 5min or more waiting for another passenger.

Although may days and times na high in demand ang Grab/Uber rides, I'm presuming na hindi naman ganun kalakas/frequent na may passenger siya all the time to the extent that he/she'd have switched the engine on & off more than what can be considered "normal" use for a day- perhaps to the extent na considered "heavy" use siguro but not that masira yung starter- note, I'm not saying it can't happen though. Wala pa naman taxi nagpareplace sa amin ng starter that I remember.

If the TS is that successful sa ganun kataas na volume ng rides niya, oh well, don't worry about it, sa dami na ng kinikita mo, just buy a new car and a new starter for the old one. Eh di dalawa na pang uber/grab unit mo