Dear Honest John
I have a new Toyota Yaris which features a rather nanny state safety device in which the clutch pedal must be pressed to enable the engine to be started.
I complained to Toyota and asked for authority to have this inhibitor deactivated as I contend that this puts a load on the crankshaft thrust bearings when there is no pressured oil present and would lead to rapid wear of the washers.
In their reply they justified this device from the safety angle, and stated that although deactivation this wouldn't invalidate the warranty itself, subsequent failure that involved the systems around starting could result in its invalidation. They also said it could have insurance implications by being out of makers spec, and the hardest part I had of taking on board was that the thrust washers were splash lubricated, I find this very hard to believe.
Can you substantiate this lubrication question.
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If you are not happy with the system for starting the car why did you buy it in the first place?
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It's an American legal requirement;also autos can only be started in "P".On one I drove in the US,you had to have your foot on the brake as well but there is no similar requirement in the EU.Most thrust bearings do not have a direct feed and are only lubricated by oil from the main bearing and splash.
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Thanks jc2 for at least one sensible reply.
Point taken about direct pressure feeds to thrust bearings, but if the oil to the mains wasn't pressure fed how would it get to the thrust washers in copious quantities ?
Fed by the pressure forcing the oil out from the mains surely.
I am old enough to remember splash fed mains & big ends and no where on a modern engine do these components or the thrust washers rely on splash lubrication.
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"Can you substantiate this lubrication question."
I am sorry me old fruit, but the answer is no. It a baseless assertion.
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TourVanMan TM < Ex RF >
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Actually I always push the clutch in when starting as I was told somewher once that this lessend the load on the battery-is this nonesense?
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I'll save you worrying.
I have a 6 year old Ford - far more unreliable than any Toyota. For the past 80,000 miles, every time it's been started, the clutch has been engaged whether it's been in gear when started, or neutral.
It's still (touch wood) fine.
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im with toyota and agree with blue haddock
why did you buy it if you dont like its fundamental starting procedure,did you not "try before you buy" then?
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Go in there, find the switch and deal with it. Then make sure that you always disengage the clutch fully before starting. This is good pracyce as it can avoid an accident and lessens the gear oil drag on the starter. Thrust bearings are lubricated via radial oil carrying grooves from the oil fed to the main bearings. I have yet to see a thrust bearing failure on any recent engine, including those (like mine) where the clutch is disengaged for every start.
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I cannot believe anyone buys a new car without driving it. To complain about the way it is started after buying is imo quite unbelievable. Did you not test drive it?
If I were Toyota I would tell you any such change invalidates all warranties as- if they approve any such change - and you subsequently have any problem with it - you can by law claim it's THEIR fault as they approved your modification.So I personally can't see them approving it. I may of course be wrong.
madf
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I'll save you worrying. I have a 6 year old Ford - far more unreliable than any Toyota. For the past 80,000 miles, every time it's been started, the clutch has been engaged whether it's been in gear when started, or neutral. It's still (touch wood) fine.
I take it you mean the clutch has always been disengaged, Adam?
This is often said to be good practice anyway - presumably because it relieves the starter of the need to move some of the bits around, as well as ensuring you don't go off at half cock if it's in gear.
I'm not qualified to say the OPs thrust bearings won't wear out but I don't think I'd be worrying. In any case, wouldn't the axial load on the crankshaft be negligible compared with that when the car is being driven under load, as well as being of short duration?
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I'm given to understand that this standard cockpit drill for Police Drivers and in all likelyhood a IAM thing as well.
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Yes - I'm sorry. I meant disengaged!
Dad taught me to do it and it's stuck ever since. I also leave the car in gear when I park it up so it helps for quick getaways too ;-)
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I'm given to understand that this standard cockpit drill for Police Drivers and in all likelyhood a IAM thing as well.
Yes that is correct.
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Thanks for your input Manatee
I would like to comment on a couple of your points
>>presumably because it relieves the starter of the need to move some of the bits around<<
This is true and especially important on commercial vehicle engine/gearbox assemblies where the size of the components in the primary drive line are large and the oil drag on them is considerable especially during cold weather. It can make the difference between an engine starting or not especially with a Dicky battery. I have used the technique of clutch disengagement to good effect in these conditions but only in an emergency.
Car components are relatively smaller and oil drag much less.
wouldn't the axial load on the crankshaft be negligible compared with that when the car is being driven under load ? <<
As far as axial load is concerned, if you have the opportunity [like with a gearbox removed and clutch assembly exposed] try and disengage a clutch with your bare hands without the assistance of the levers and hydraulic advantage you normally have between the pedal and the release bearing, you won't be able to, and this is the magnitude of the axial thrust during clutch disengagement that you are subjecting the unlubricated thrust bearings to. Transmission stresses of whatever magnitude are not transmitted to the crankshaft but contained in the various transmission cases/boxes
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Transmissionstresses of whatever magnitude are not transmitted to the crankshaft but contained in the various transmission cases/boxes
I confess I hadn't thought this through properly - splined shafts and all that - stupid comment from me anyway as your point was about lubrication.
Is your objection mainly to the compulsion or do you think there is s real risk to the bearings?
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Hello again Manatee
>>stupid comment from me<<
Nothing stupid about learning Manatee I'm glad to have stimulated the mind.
>>real risk to the bearings<<
I don't really think my bearings will be damaged, I'm sure Toyota have carried out sufficient R&D to prevent that. But it is still technically wrong to load an unlubricated bearing.
If Adam{P}'s 80,000 mile Ford has remained unscathed with this abuse even without his superstitious preventive action I'm now reassured - thanks Adam.
I do find Toyota's abhorrent nanny state attitude to this feature a close second in the objection score though.
Just like Ziggy and his audible seat belt warning, I bet he hopes it does go wrong.
In my learner driving days the start up procedure was :---
1.Handbrake ON.
2.Gearbox in Neutral.
3.Switch on and observe warning lights, if OK
4.Start engine
Mind you in those days we had to do hand signals and double declutch to change gears so maybe thinking has changed.
Comments from an approved /registered driving instructor would be interesting at this point.
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I can't tell if you're being sarcastic but...you're welcome!
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I can't tell if you're being sarcastic but...you're welcome!<<
Moi !! Being sarcastic?, never let it be said.
But do you actually cross your fingers when starting ?
There must be an E.U. directive about this.
Sorry Adam{P} Now I'm getting silly.
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In my learner driving days the start up procedure was :--- 1.Handbrake ON. 2.Gearbox in Neutral. 3.Switch on and observe warning lights, if OK 4.Start engine Mind you in those days we had to do hand signals and double declutch to change gears so maybe thinking has changed. Comments from an approved /registered driving instructor would be interesting at this point.
you had a bad instructor, we were all taught to lesson the load by dipping the clutch, as batteries were crap back then.
i think you speak with forked tongue
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Actually I always push the clutch in when starting as I was told somewher once that this lessend the load on the battery-is this nonesense?
No it is good practice. I have always done the same. As I have always worn a seatbelt. But I cannot tolerate that warning beep 'reminding' me to belt up, and I would not tolerate this nonesense.
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In the old days-and I mean old-we were told to push in the clutch to reduce load on the starter when starting from cold but only on engines with a ball-race clutch release bearing;many cars in those days had a solid block of carbon as a release bearing and pushing in the clutch on these increased the load on the starter.
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