A good digital oscilloscope?
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From: Rich Grise on 15 Dec 2009 14:26 On Tue, 15 Dec 2009 11:07:15 -0800, Joerg wrote: > Joel Koltner wrote: >> "Joerg" <invalid(a)invalid.invalid> wrote in message >> news:7opq9mF3qhhh3U1(a)mid.individual.net... >>> We still learned how to hobble a stalled car off railroad tracks by >>> using starter, clutch and first gear. Of course now they have switches >>> on the clutch that don't let the starter engage unless fully depressed >>> which defeats that extra safety measure. >> >> I would have to guess the the ratio of how often people damaged or >> ruined their starter or gearbox from trying to start without the clutch >> all the way in to how often someone ended up with a stalled car on >> railroad tracks is perhaps about a million to one? :-) > > AFAIK you can't easily ruin the gear box even with the clutch released > and in gear. The starter, yes, but even that will take a while if it's a > good quality one. See my prevous post. ;-) It's been my experience that Fords will run forever if you keep the oil topped up. :-) (at service station: "Fill up the oil and check the gas.") ;-) Cheers! Rich
From: John Larkin on 15 Dec 2009 14:26 On Tue, 15 Dec 2009 10:52:38 -0800, "Joel Koltner" <zapwireDASHgroups(a)yahoo.com> wrote: >"Joerg" <invalid(a)invalid.invalid> wrote in message >news:7opq9mF3qhhh3U1(a)mid.individual.net... >> We still learned how to hobble a stalled car off railroad tracks by using >> starter, clutch and first gear. Of course now they have switches on the >> clutch that don't let the starter engage unless fully depressed which >> defeats that extra safety measure. > >I would have to guess the the ratio of how often people damaged or ruined >their starter or gearbox from trying to start without the clutch all the way >in to how often someone ended up with a stalled car on railroad tracks is >perhaps about a million to one? :-) My MGs had horribly unreliable hydraulic clutches. I got pretty good at clutchless driving, which involves starting the car in first gear. > >I keep hoping that one of these days an inexpensive and reliable continuously >variable transmission finds its way into cars. That's been the ME's Holy Grail for decades now. They have no equivalent to a switching regulator; they are still tap switching! John
From: John Larkin on 15 Dec 2009 14:28 On Tue, 15 Dec 2009 10:22:41 -0800, Joerg <invalid(a)invalid.invalid> wrote: >John Larkin wrote: >> On Tue, 15 Dec 2009 08:02:56 -0800, Joerg <invalid(a)invalid.invalid> >> wrote: >> >>> Jim Thompson wrote: >>>> On Tue, 15 Dec 2009 07:52:54 -0600, Jim Yanik <jyanik(a)abuse.gov> >>>> wrote: >>>> >>>>> "Joel Koltner" <zapwireDASHgroups(a)yahoo.com> wrote in >>>>> news:H3DVm.414201$ua.294023(a)en-nntp-05.dc1.easynews.com: >>>>> >>>>> >>>>>> Hey, don't cars with automatics generally get a mile or two per gallon >>>>>> better mileage than manuals? ;-) >>>>>> >>>>>> ---Joel >>>>>> >>>>>> >>>>> Manuals usually get better mileage,but that is changing in -some- >>>>> models,because of the addition of lockup torque converters and CVTs. >>>>> >>>>> automatics eliminate the need for driver competence. >>>>> >>>>> Note that "unintended accelleration" crashes occur only with automatics. >>> They should start teaching the basics again in drivers ed. Like how a >>> car works. In Germany you used to not be able to get a license unless >>> you could explain how an engine worked, and how other stuff such as >>> clutch, gear box or differential worked. >>> >>> We still learned how to hobble a stalled car off railroad tracks by >>> using starter, clutch and first gear. Of course now they have switches >>> on the clutch that don't let the starter engage unless fully depressed >>> which defeats that extra safety measure. >>> >>> >>>> You're living in the past... I can't recall any car using a purely >>>> "slush" type torque converter for at least 30 years, maybe longer. >>>> >>> But they all have to keep sloshing around some of the oil around the >>> shaft lock. There's a reason why even new automatic transmissions run >>> hotter than gear boxes. And warmer = more losses. >> >> My Audi is weird: it's a 6-speed automatic, but it has no torque >> converter. It has two gear trains, one for odd gears and one for even, >> and each train has its own automated clutch. >> >> Something like this: >> >> http://www.blogcdn.com/green.autoblog.com/media/2007/09/dsg_audi.jpg >> >> http://images.google.com/imgres?imgurl=http://www.my-gti.com/wp-content/uploads/dsg_trans_7_speed__550nm_1.jpg&imgrefurl=http://www.my-gti.com/887/volkswagen-dsg-7-speed-dual-clutch-gearbox-high-output&usg=__HFLOWMT2oKZ_i_DYIYjnc-zry5g=&h=905&w=1280&sz=221&hl=en&start=137&sig2=GfNeSyQkB6wul0biVhiuJQ&um=1&tbnid=1b9WYcJGttn2QM:&tbnh=106&tbnw=150&prev=/images%3Fq%3Daudi%2Bdrive%2Btrain%2Bdual%2Bclutch%26ndsp%3D20%26hl%3Den%26sa%3DN%26start%3D120%26um%3D1&ei=esMnS9OnHYmssQPA6fG1DA >> > >Wow, that looks like one expensive repair job if anything breaks in there. True, but any automatic tranny is complicated. Replacing the clutches is probably no worse than replacing the planetary bands in a regular automatic. And 4WD is always more hardware. John
From: Joel Koltner on 15 Dec 2009 14:30 Here's what the Car Talk guys have to say: Tom: So there's no longer any good economic argument for driving a standard transmission...especially when you factor in the inevitable clutch job or two you'll need. It's purely a matter of preference these days. If you like shifting, then get a stick shift. Ray: But if you have better things to do with your right hand and left foot while you drive, get an automatic, and don't worry about the mileage difference. (There's more discussion about how these things work -- they're targeting a rather non-technical audience, of course -- here: http://www.cartalk.com/content/columns/Archive/1993/September/09.html . I realize that Joerg managed to drive his Citreon a quarter-million miles without ever needing a new clutch, but the average soccer mom isn't quite so gentle to them. :-) ) ---Joel
From: Rich Webb on 15 Dec 2009 14:41
On Tue, 15 Dec 2009 11:07:15 -0800, Joerg <invalid(a)invalid.invalid> wrote: >AFAIK you can't easily ruin the gear box even with the clutch released >and in gear. The starter, yes, but even that will take a while if it's a >good quality one. Or even a not-so-good quality one. Had the clutch cable break on a Renault once upon a time. Speed-match shifting isn't so bad but there were a few places where I just had to stop. So, stop. When it was time to go, hit the starter and baby the throttle a bit. Luckily (hah) there were no up-hill starts required. Since that car also ate speedometer cables and ECUs, had a brake line split, and the alternator fall off, I'd not wager that the starter was within throwing distance of "good quality." ;-) -- Rich Webb Norfolk, VA |