To lovers of stop/start

[Stevey Y]

Hi for all the people who value stop start, had a rather interesting Volvo/Ford engineer as a passenger this week and rather than a lecture on electric vehicles he had my attention talking about stop/start, mine as usual was zoned out and he enquired why, I explained that my theory was it put added wear on the starter and ring gear he laughed and said it was highly unlikely as both components were beefed up to accommodate the extra loads but in fact my theory wasn't as far off as I thought, he then went on to tell me he was working with the oil companies to produce new nano tech oils because the existing engine technology is suffering with stop/start  as when the engine is running the pressured oil forms a hydro barrier between the crank journals and the bearings, when the engine is stopped the journal/bearing come into contact and when the engine starts again there is a lapse between the oil pressure arriving to reinstate the hydro barrier, I.E. extra wear, he then explained that a normal engine is rated to start 50,000 times during its life and a stop/start engine will perform the same function over 500,000 times, so you can see where this is going and apparently the race is on to produce a coating for crank bearings that is self lubricating Teflon and Iron Oxide, Yes, Rust, which in fine particles reduces friction co efficient by 50%, also he explained that the engine conditions for stop/start have to be ideal as it won't work when the engine is too hot/cold or if you have the aircon working flat out, I have never experienced this as my stop/start is never on.

Steve.

[audia4b5kev]

i use slik 50               since i was 16  in my motobikes  and all cars i have owend      never let me down yet 

[DuncanH]

Hi,, not totally correct, when the engine stops at any time the oil pressure stops, but there is always a film of lubricant between the crankshaft and the white metal bearing. The technology behind automotive lubricants present day are very advanced. Speaking with a friend at fuchs he said they supplied oils to various manufacturers many years ago when stop/start was in it development stages.

[Magnet]

Thanks Duncan,

‘…not totally correct…’ Um! 

Let’s try and boil this down:-

Is stoping and restarting an engine (with zero oil pressure) unlikely to have any negative effect on the engine - particularly over many years of repeating that procedure numerous times/day?

If your answer is ‘No it doesn’t have an adverse affect’ ,then it would be great to hear your reasoning to support that.

As I see it we have two camps here who are not stop/start averse:-

Environment supportive motorists who are happy to accept the engineering averse system, based on the ‘temporarily on stop’ emissions reduction. I certainly don’t have any any argument with that, since I guess they know that they are paying the cost. 
 

Other group - my car has stop/start, and that’s posh and somewhat impressive, and I want it to work for that reason, and it won’t be impressive if I switch it off. Different, and they too obviously know about the increased wear element.

Back to your ‘… not totally correct….’ Interesting third group? 
Many thanks Duncan.

Kind regards,

Gareth. 

[DuncanH]

Gareth, if you notice I made no comment about the start stop technology! My comment was based solely on the comment about there being no oil and metal to metal contact. Not here to nit pick or argue just passing factual comment as you are doing!

[Magnet]

That’s fine Duncan. Best left as no score draw half time then.

[Stevey Y]

12 hours ago, DuncanH said:

Hi,, not totally correct, when the engine stops at any time the oil pressure stops, but there is always a film of lubricant between the crankshaft and the white metal bearing. The technology behind automotive lubricants present day are very advanced. Speaking with a friend at fuchs he said they supplied oils to various manufacturers many years ago when stop/start was in it development stages.

Hi I have done a fair amount of research on this and from personal experience would concur with what the guy said the oil film you mentioned is in fact physical but there is contact which is why some engines with middling milage I have worked on knock when being started from cold this is through naturally occurring wear on the bearings which would lead one to believe  that due to poor maintenance or low quality oil even some being how far they can go after the service due message comes on, as far as I can see given some of the parameters mentioned stop/start would merely accelerate the wear process, as for the lubricants they have been selling advanced oils for years but most of these are sold at a premium and contain PTFE same as the Slick 50 Kev mentioned, reading between the lines car producers are not necessarily worried by problems that occur outside the warranty period as in the case of Audi who are quite happy to sell you a short engine for £5000, but in saying that why are they so suddenly interested in beefing up con rod bearings, someone somewhere is having problems inside the warranty.

Steve.

[CraigR1977]

I’d like to know what the offset is in terms of carbon released by the engine running versus the extra carbon released from producing the bigger battery required to power the system. Had to buy a battery for our C7 just before we sold it last week. !Removed! expensive.

 On a side note that is without doubt the best car I have ever owned. 2.0 tdi S line Quattro. The kids are a bit bigger now and we didn’t need the load space and it stuck out of parking spaces… apparently. 

[Stevey Y]

6 hours ago, CraigR1977 said:

I’d like to know what the offset is in terms of carbon released by the engine running versus the extra carbon released from producing the bigger battery required to power the system. Had to buy a battery for our C7 just before we sold it last week. !Removed! expensive.

 On a side note that is without doubt the best car I have ever owned. 2.0 tdi S line Quattro. The kids are a bit bigger now and we didn’t need the load space and it stuck out of parking spaces… apparently. 

Hi same as electric cars no one wants to publish the carbon emissions produced in manufacturing or the fact that dead batteries for the car are virtually non recyclable and extremely toxic, but that won't matter in a world of we only want you to believe implicitly what we tell you, in fact the dark side of production is not good P.R. same as where did the last strain of Covid originate.

Steve.

[coupe4]

its an interesting debate folks,i personally hate the start/stop system and when i use our a6 i turn it off the minute i get into the car!

[CraigR1977]

22 minutes ago, coupe4 said:

its an interesting debate folks,i personally hate the start/stop system and when i use our a6 i turn it off the minute i get into the car!

We do as well, there’s apparently a plug and play delete you can buy for the A4 B9 that basically just inverts the switch, so the default position is off. I think I’ll give one a try. Other than that it’s a vcds 1/2 delete that stops it working if the a/c is switched on as far as I know. Unfortunately, I don’t think either is possible with the A6 C7.

[Stevey Y]

13 minutes ago, CraigR1977 said:

We do as well, there’s apparently a plug and play delete you can buy for the A4 B9 that basically just inverts the switch, so the default position is off. I think I’ll give one a try. Other than that it’s a vcds 1/2 delete that stops it working if the a/c is switched on as far as I know. Unfortunately, I don’t think either is possible with the A6 C7.

Hi you can disable it with VCDS, the system won't work anyway with the aircon on as that would be to much loading trying to start it frequently and drag the compressor round whilst starting.

Steve.

[coupe4]

i must see can i disable it so with the vcds,i must also get more familiar with the vcds as i only use the basic functions on it up to now.

[Stevey Y]

21 hours ago, coupe4 said:

i must see can i disable it so with the vcds,i must also get more familiar with the vcds as i only use the basic functions on it up to now.

Hi you would be amazed at what you can do with it, activate dormant functions on your car, check soot and ash levels in the DPF even when the last regeneration was as well as reset the Adblue level if that goes wonky, it will even let you check the amount in the tank and then there is a host of re adaption portals for just about any sensor/valve on the engine.

Steve.