All modern cars - Stop start systems

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Thu 12 Nov 2015 16:33
All modern cars - Stop start systems - Steveieb
Walking along a busy road in town all I could hear was the sound of starter motors clicking as the cars shut down on stopping and started up when they started.

What damage these must be doing to the starter motors ? And are they fitted to autos ?
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Thu 12 Nov 2015 16:39
All modern cars - Stop start systems - RT

Damage? None, they're designed for that job

Autos? Yes, my Touareg's got it along with "coasting" - decoupling the gearbox from engine when lifting off the throttle.

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Thu 12 Nov 2015 17:14
All modern cars - Stop start systems - Falkirk Bairn

>>Damage? None, they're designed for that job

I have owned cars for some 51 years and only ever had 1 starter motor & 1 x dynamo (yes, dynamo) that has had to be repaired / replaced.

As yet I do not own a start /stop alt/starter but my sons have cars with these - we will just need to wait and see if they are as reliable " on the road" and not just on test bed mules.

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Thu 12 Nov 2015 17:09
All modern cars - Stop start systems - FP

"What damage these must be doing to the starter motors ?"

You're making the mistake of assuming that stop-start systems use a standard (old-fashioned) starter motor which engages the flywheel.

Most, if not all, stop-start systems use a combined alternator/starter.

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Thu 12 Nov 2015 17:21
All modern cars - Stop start systems - skidpan

Most, if not all, stop-start systems use a combined alternator/starter.

We are now on our 4th car with stop/start.

BMW, Kia, Seat, Nissan.

All use the starter motor.

As far as I am aware only hybrids like the Prius have the alternator in the transmission which can have a dual use.

Since the alternator is normally driven by a belt (has been on every car I have owned) it would need to be an incredibly good belt to turn the engine over.

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Thu 12 Nov 2015 18:00
All modern cars - Stop start systems - Engineer Andy

If I recall, the batteries, even for the standard (non Prius-types) cars are 'special' higher duty ones to cope with the large number of start cycles - how much expensive are they than 'normal' car batteries? - my last one cost (including fitting at the dealer) a whopping £120.

Is there a button/function so you can turn off the star-stop feature (say in hot weather when in jig-jog queues on the motorway (when the engine would regularly need to kick in to keep the A/C going as well as move forward a few meters? I wasn't sure if its a feature in all cars with this technology, or just the newest or higher spec models/makes.

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Thu 12 Nov 2015 18:11
All modern cars - Stop start systems - skidpan

Is there a button/function so you can turn off the star-stop feature (say in hot weather when in jig-jog queues on the motorway (when the engine would regularly need to kick in to keep the A/C going as well as move forward a few meters? I wasn't sure if its a feature in all cars with this technology, or just the newest or higher spec models/makes.

On all of ours there has been a button to disable it but you need to do it every time you get in the car, its not a permanant on/off.

I have found in all of ours that in traffic 4 cycles of stop/start is about the most you can expect before it stops working until you get some charge in the battery.

On some I am told stop/start does not work when A/C is on but that has not been the case with ours. However, sit in busy traffic with the A/C on and the car will start when it feels the need.

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Thu 12 Nov 2015 18:49
All modern cars - Stop start systems - xtrailman

Mazda cx-5 petrol uses two cylinders firing to restart the engine.

Diesel uses the starter motor a heavy duty type, as mentioned the battery is also a special type, replacement for mine is well over £160.

Among other things there are more plates which are a lot closer together than a standard battery.

There is also a few conditions for the i-stop to work, one is the battery must have 80% capacity. I often use the dash off switch to turn it off. both auto and manual versions have it.

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Thu 12 Nov 2015 21:33
All modern cars - Stop start systems - daveyjp
5 years and 50,000 miles with a Mercedes stop start. Lots of urban journeys where stop start was activated and not a single problem. Similar case with our other Mercedes which is 3.5 years old.

Mercedes don't use the starter motor, they use a modified alternator.
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Thu 12 Nov 2015 21:59
All modern cars - Stop start systems - xtrailman

http://media.daimler.com/dcmedia/0-921-1320460-1-1336960-1-0-0-0-0-0-11702-854934-0-1-0-0-0-0-0.html

This sound similar to the Mazda system to me?

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Thu 12 Nov 2015 23:02
All modern cars - Stop start systems - FP

I didn't do the research properly. Many systems do use the old-fashioned starter motor, though upgraded to cope.

Peugeot/Citroen do use (at least in some models) a combined alternator/starter. It is an elegant though costly solution.

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Thu 12 Nov 2015 22:02
All modern cars - Stop start systems - puckdrop

Toyota hybrids use one of the two motors as the starter, a generator, and a gear provider (the speed of one of the motors determines engine speed etc )

The Honda IMA system used in the Insight and outgoing Jazz (and possibly others like the CRZ etc. ) use the electric motor as a starter, but also have a traditional starter motor in case the IMA system is unavailable.

The start/stop motors of todays generation will be designed for the load. Probably one concern is the operation of the ECU regarding the engine starting. For example, the Toyota hybrid system spins the combustion engine up to 1,000 revs to build oil pressure and circulation within the engine before actually firing it. I wonder if "traditional" start-stop cars do the same ? And what the effect is of not doing it long term ?

Edit: Stop start is also not new. More recent 'modern' attemts by VW include the Golf Ecomatic, and the VW Lupo 3L ( not a 3 litre engine - but 3L per 100Km consumption lol ) - look them up.

Edited by puckdrop on 12/11/2015 at 22:04

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Thu 12 Nov 2015 22:20
All modern cars - Stop start systems - SteveLee

You can immobilise the stop/start system on most cars - which is a boon if you intend to keep the car for a long time as the heavy duty starter motor should last the lifetime of the car if you disable the stop/start nonsense.

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Fri 13 Nov 2015 20:24
All modern cars - Stop start systems - nailit

The mazda I-stop and I-loop (?) System on at least the new 6 sportnav car, uses the high (est) compression of the engine to restart together with (when fully charged) electric power from a huge capacitor which is quickly charged at high voltage from deceleration/braking. A capacitor charges many more times faster than a battery. The mazda engine is allegedly the highest compression mass manufactuted engine.

Sorry about any typos. On mobile....:-)

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Fri 13 Nov 2015 20:30
All modern cars - Stop start systems - nailit

Addendum. Forgot to mention 2.0 ltr petrol. Doesn't use battery power if capicitor full and...I think doesnt use starter motor as it 'holds the compression somehow. I need to re visit the documentation. ...seen a diagram somewhere. ..

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Fri 13 Nov 2015 20:40
All modern cars - Stop start systems - barney100

I really dislike my stop start feature and turn it off as soon as the car starts at first. Why can't you turn the thing off permanently or can you?

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Fri 13 Nov 2015 20:50
All modern cars - Stop start systems - nailit

I just keep my foot on the clutch if I wish to keep the engine from stopping. Which to be honest is most of the time unless really bad.

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Sat 14 Nov 2015 08:28
All modern cars - Stop start systems - skidpan

I really dislike my stop start feature and turn it off as soon as the car starts at first. Why can't you turn the thing off permanently or can you?

Stop start significantly reduces CO2 in the lab tests thus significantly reduces your VED. If you could turn it off permanantly you would own a non stop/start car which would be classed in a higher band.

We had 2 Volvo V50's at work, identical cars, one non stop start one stop start, think the stop/start one was £150 extra. Both did exactly the same mpg over the 5 years we had them but the stop/start one was over £100 a year less VED.

Its not that hard to press a button everytime you start the car is it.

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Sat 14 Nov 2015 08:48
All modern cars - Stop start systems - dan86

Stop start may only save a thimble of fuel but if it is switching the engine off when it'starts at its least productive then it's a good thing IMHO. When a engine is just idaling in traffic it's just wasting fuel and creating emissions. I don't own a car with stop start and TBH don't do loads of miles sitting in traffic but I think it would be handy at traffic lights ect.

Edited by dan86 on 14/11/2015 at 08:49

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Sat 14 Nov 2015 08:55
All modern cars - Stop start systems - csgmart

Stop start may only save a thimble of fuel but if it is switching the engine off when it'starts at its least productive then it's a good thing IMHO. When a engine is just idaling in traffic it's just wasting fuel and creating emissions. I don't own a car with stop start and TBH don't do loads of miles sitting in traffic but I think it would be handy at traffic lights ect.

Exactly - I really don't know why some people get so worked up over something so simple to use.

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Sat 14 Nov 2015 09:33
All modern cars - Stop start systems - Engineer Andy

The problem using this feature is that they only work well when the car isn't needing to use significant quantities of electrical power (using the engine to generate it via the alternator), such as the heater/fan or especially the A/C, thus the stop-start system only works well at the times of year when you're not using either - how often does that happen? Probably a couple of months a year at best. Outside of that the engine will soon re-start (even when you're stopped for ages in traffic) regularly to keep the battery charged because of the severe drain caused by the use of the high-drain electrical systems.

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Sat 14 Nov 2015 11:10
All modern cars - Stop start systems - jc2

Most modern cars are designed to start on the first or second full revolution of the engine-prolonged cranking is a thing of the past.

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Sat 14 Nov 2015 16:39
All modern cars - Stop start systems - grumpyscot

You obviously haven't driven a Vauxhall recently then!

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Sat 14 Nov 2015 17:03
All modern cars - Stop start systems - hillman

"Mazda cx-5 petrol uses two cylinders firing to restart the engine."

I once owned a Morris minor with a side valve engine that regularly used to blow the head gasket. Much of the radiator water was deposited in the cylinders and when I came to start the engine there was a thump as the piston hit the water. I would then get out the starting handle and ease the water past the rings into the sump. When it was free I would spin the handle until the engine fired on one cylinder, that encourage a second cylider to fire and I then could start off home. The rest of the cylinders soon kicked in.

We recently rented a Vauxhall Insignia and that had 'stop start'. After the first few miles we no longer noticed it. The rest of the innovations, especially the electric parking brake, I didn't like

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Sat 14 Nov 2015 19:54
All modern cars - Stop start systems - jc2

You obviously haven't driven a Vauxhall recently then!

I did say "most"!!

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