http://groups.google.com/group/rec.autos.makers.honda?hl=en
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Today's topics:
* 2009 Odyssey Heater - 8 messages, 5 authors
http://groups.google.com/group/rec.autos.makers.honda/t/f8bc32418f5f599a?hl=en
* new Honda CR-V break in - 13 messages, 5 authors
http://groups.google.com/group/rec.autos.makers.honda/t/e22c4e2539b2b72e?hl=en
* 2009 Civic Ex excessive road noise - 4 messages, 2 authors
http://groups.google.com/group/rec.autos.makers.honda/t/4366bc21ccff7c3a?hl=en
==============================================================================
TOPIC: 2009 Odyssey Heater
http://groups.google.com/group/rec.autos.makers.honda/t/f8bc32418f5f599a?hl=en
==============================================================================
== 1 of 8 ==
Date: Fri, Jan 22 2010 7:45 pm
From: Tegger
Piperson <ppsn168@yahoo.com> wrote in news:lDt6n.1916$1m3.58@newsfe11.iad:
> My first venture into the Honda line has been received with mixed
> reviews. The vehicle in question is a new 2009 Honda Odyssey Touring.
> The only option added was the trailering package which was dealer
> installed. Some nice feature and some just plain disappointing. One of
> my biggest regrets was not opting for all wheel drive. Traction in Ohio
> winters is tenuous at best.
>
> More importantly, in Ohio winters, I would like a bit more heat! I have
> had it back to the dealers indicating it just takes too long for the
> engine to warm up. It never reaches half way on the gauge and is
> certainly less than satisfying in warming the the interior of the
> vehicle. The dealer mechanic has measured the air temp coming out of
> the dash as about 160 F which sounds okay, but has not offered the
> engine temperature. Having called "the factory", it would seem that
> that check is not necessary. The performance would indicate to me that
> the thermostat does not allow the engine temperature to reach the 195
> design level.
>
I think you're confusing dash vent temperatures with engine head
temperatures.
Assuming a 174F (78C) OEM thermostat and a fully-warm engine, an infrared
thermometer aimed at the upper rad hose outlet at the head will display
about 205F. Anywhere other than that, the thermometer will read drastically
lower. I'm very surprised the tech was able to get 160F at the vents.
That's hotter than the hot water tap in your house. I'd expect more like 70
or 75.
--
Tegger
The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/
== 2 of 8 ==
Date: Sat, Jan 23 2010 3:24 am
From: "Elmo P. Shagnasty"
In article <Xns9D08E68B2DA73tegger@208.90.168.18>,
Tegger <invalid@invalid.inv> wrote:
> I've been hearing this for much more than a year. Not just for Hondas but
> for Toyotas as well.
>
> At first I thought it had to do with defective thermostats. And indeed,
> people who had their thermostats replaced under warranty DID report an
> improvement. But the perceived improvement may have been imaginary.
>
> Given the frequency with which I'm seeing this problem, I wonder if there
> has been a regulatory change to emissions control laws. NOx are a product
> of excessive combustion chamber temperatures. Cool the chamber and you
> reduce NOx. Cool it too much without restricting the cooling system and you
> may actually affect interior heater performance.
>
> I see absolutely nothing in any of the official documentation I have (which
> is now extensive) relating to the problem, so evidently automakers do not
> believe there is an issue.
Frankly, the first thing that came to my mind was that he's warming up
the car in the driveway and complaining that it's not getting warm
enough just sitting there
That's just how modern cars work, of course; you have to drive them to
get the temps up. Been that way for years and years.
The clue was his claim that the temp needle never gets to the middle.
That's simply not true. When the engine is running properly, the body
computer will move the temperature needle to the middle to indicate "all
is well". It won't fluctuate up and down with minor variations. If the
needle is in fact not getting to the middle during normal driving, then
something is indeed wrong.
== 3 of 8 ==
Date: Sat, Jan 23 2010 7:08 am
From: jim beam
On 01/22/2010 07:39 PM, Tegger wrote:
> Piperson<ppsn168@yahoo.com> wrote in news:lDt6n.1916$1m3.58@newsfe11.iad:
>
>> My first venture into the Honda line has been received with mixed
>> reviews. The vehicle in question is a new 2009 Honda Odyssey Touring.
>> The only option added was the trailering package which was dealer
>> installed. Some nice feature and some just plain disappointing. One of
>> my biggest regrets was not opting for all wheel drive. Traction in Ohio
>> winters is tenuous at best.
>>
>> More importantly, in Ohio winters, I would like a bit more heat! I have
>> had it back to the dealers indicating it just takes too long for the
>> engine to warm up. It never reaches half way on the gauge and is
>> certainly less than satisfying in warming the the interior of the
>> vehicle. The dealer mechanic has measured the air temp coming out of
>> the dash as about 160 F which sounds okay, but has not offered the
>> engine temperature. Having called "the factory", it would seem that
>> that check is not necessary. The performance would indicate to me that
>> the thermostat does not allow the engine temperature to reach the 195
>> design level.
>>
>> Any ideas out there about how I might pursue an improvement?
>>
>
>
>
> I've been hearing this for much more than a year. Not just for Hondas but
> for Toyotas as well.
>
> At first I thought it had to do with defective thermostats. And indeed,
> people who had their thermostats replaced under warranty DID report an
> improvement. But the perceived improvement may have been imaginary.
>
> Given the frequency with which I'm seeing this problem, I wonder if there
> has been a regulatory change to emissions control laws. NOx are a product
> of excessive combustion chamber temperatures. Cool the chamber and you
> reduce NOx. Cool it too much without restricting the cooling system and you
> may actually affect interior heater performance.
but you'd then get excess hydrocarbon output instead.
otoh, if this is real, because ethanol has a lower calorie content, i
wonder if it could be high ethanol gasoline? [just an idle wonder - i
have no idea about comparative combustion temps.]
>
> I see absolutely nothing in any of the official documentation I have (which
> is now extensive) relating to the problem, so evidently automakers do not
> believe there is an issue.
if ethanol, it would not be an issue they could address easily. there
are two cooling circuits on modern engines - and one of them circulates
all the time. closing that off to get a higher temperature quicker
might lead to local hot-spots - you have to assume the manufacturers
have done /some/ homework on this.
manufacturers could of course move to an electronically controlled
thermostat and have the engine temp managed so it's warmer in winter and
cooler in the summer, but i'm not sure how the computer would know what
was "not warm enough" for any individual driver.
== 4 of 8 ==
Date: Sat, Jan 23 2010 7:08 am
From: jim beam
On 01/22/2010 07:00 PM, Piperson wrote:
> My first venture into the Honda line has been received with mixed
> reviews. The vehicle in question is a new 2009 Honda Odyssey Touring.
> The only option added was the trailering package which was dealer
> installed. Some nice feature and some just plain disappointing. One of
> my biggest regrets was not opting for all wheel drive. Traction in Ohio
> winters is tenuous at best.
>
> More importantly, in Ohio winters, I would like a bit more heat! I have
> had it back to the dealers indicating it just takes too long for the
> engine to warm up. It never reaches half way on the gauge and is
> certainly less than satisfying in warming the the interior of the
> vehicle. The dealer mechanic has measured the air temp coming out of the
> dash as about 160 F which sounds okay, but has not offered the engine
> temperature. Having called "the factory", it would seem that that check
> is not necessary. The performance would indicate to me that the
> thermostat does not allow the engine temperature to reach the 195 design
> level.
>
> Any ideas out there about how I might pursue an improvement?
i think you should check the facts. get an obdII code reader and use it
to find out what the actual coolant temperature is from the engine
computer output. if it's below 78C, you do indeed have a problem. if
not, you don't.
== 5 of 8 ==
Date: Sat, Jan 23 2010 7:08 am
From: jim beam
On 01/23/2010 03:24 AM, Elmo P. Shagnasty wrote:
> In article<Xns9D08E68B2DA73tegger@208.90.168.18>,
> Tegger<invalid@invalid.inv> wrote:
>
>> I've been hearing this for much more than a year. Not just for Hondas but
>> for Toyotas as well.
>>
>> At first I thought it had to do with defective thermostats. And indeed,
>> people who had their thermostats replaced under warranty DID report an
>> improvement. But the perceived improvement may have been imaginary.
>>
>> Given the frequency with which I'm seeing this problem, I wonder if there
>> has been a regulatory change to emissions control laws. NOx are a product
>> of excessive combustion chamber temperatures. Cool the chamber and you
>> reduce NOx. Cool it too much without restricting the cooling system and you
>> may actually affect interior heater performance.
>>
>> I see absolutely nothing in any of the official documentation I have (which
>> is now extensive) relating to the problem, so evidently automakers do not
>> believe there is an issue.
>
> Frankly, the first thing that came to my mind was that he's warming up
> the car in the driveway and complaining that it's not getting warm
> enough just sitting there
good point.
>
> That's just how modern cars work, of course; you have to drive them to
> get the temps up. Been that way for years and years.
>
> The clue was his claim that the temp needle never gets to the middle.
> That's simply not true. When the engine is running properly, the body
> computer will move the temperature needle to the middle to indicate "all
> is well". It won't fluctuate up and down with minor variations. If the
> needle is in fact not getting to the middle during normal driving, then
> something is indeed wrong.
yup.
== 6 of 8 ==
Date: Sat, Jan 23 2010 8:22 am
From: TomP
Your Honda dealer can connect the HDS to the vehicle and check ECT in real
time. That should settle the discussion whether there is a problem or not.
If they really want to go the extra mile; they can repeat the same test on
another like vehicle.
--
Tp,
-------- __o
----- -\<. -------- __o
--- ( )/ ( ) ---- -\<.
-------------------- ( )/ ( )
-----------------------------------------
No Lawsuit Ever Fixed A Moron...
== 7 of 8 ==
Date: Sat, Jan 23 2010 2:27 pm
From: Piperson
I never warm the car up in the driveway, except to clear the windshield.
I get in it and go, and expect when I hit the signal 1 mile away, I am
getting some heat out of the vents, just like the other three cars I
drive. It isn't happening on the Odyssey, until nearly the second mile.
Tom
On 1/23/2010 6:24 AM, Elmo P. Shagnasty wrote:
> In article<Xns9D08E68B2DA73tegger@208.90.168.18>,
> Tegger<invalid@invalid.inv> wrote:
>
>> I've been hearing this for much more than a year. Not just for Hondas but
>> for Toyotas as well.
>>
>> At first I thought it had to do with defective thermostats. And indeed,
>> people who had their thermostats replaced under warranty DID report an
>> improvement. But the perceived improvement may have been imaginary.
>>
>> Given the frequency with which I'm seeing this problem, I wonder if there
>> has been a regulatory change to emissions control laws. NOx are a product
>> of excessive combustion chamber temperatures. Cool the chamber and you
>> reduce NOx. Cool it too much without restricting the cooling system and you
>> may actually affect interior heater performance.
>>
>> I see absolutely nothing in any of the official documentation I have (which
>> is now extensive) relating to the problem, so evidently automakers do not
>> believe there is an issue.
>
> Frankly, the first thing that came to my mind was that he's warming up
> the car in the driveway and complaining that it's not getting warm
> enough just sitting there
>
> That's just how modern cars work, of course; you have to drive them to
> get the temps up. Been that way for years and years.
>
> The clue was his claim that the temp needle never gets to the middle.
> That's simply not true. When the engine is running properly, the body
> computer will move the temperature needle to the middle to indicate "all
> is well". It won't fluctuate up and down with minor variations. If the
> needle is in fact not getting to the middle during normal driving, then
> something is indeed wrong.
== 8 of 8 ==
Date: Sat, Jan 23 2010 2:57 pm
From: jim beam
On 01/23/2010 02:27 PM, Piperson wrote:
> On 1/23/2010 6:24 AM, Elmo P. Shagnasty wrote:
>> In article<Xns9D08E68B2DA73tegger@208.90.168.18>,
>> Tegger<invalid@invalid.inv> wrote:
>>
>>> I've been hearing this for much more than a year. Not just for Hondas
>>> but
>>> for Toyotas as well.
>>>
>>> At first I thought it had to do with defective thermostats. And indeed,
>>> people who had their thermostats replaced under warranty DID report an
>>> improvement. But the perceived improvement may have been imaginary.
>>>
>>> Given the frequency with which I'm seeing this problem, I wonder if
>>> there
>>> has been a regulatory change to emissions control laws. NOx are a
>>> product
>>> of excessive combustion chamber temperatures. Cool the chamber and you
>>> reduce NOx. Cool it too much without restricting the cooling system
>>> and you
>>> may actually affect interior heater performance.
>>>
>>> I see absolutely nothing in any of the official documentation I have
>>> (which
>>> is now extensive) relating to the problem, so evidently automakers do
>>> not
>>> believe there is an issue.
>>
>> Frankly, the first thing that came to my mind was that he's warming up
>> the car in the driveway and complaining that it's not getting warm
>> enough just sitting there
>>
>> That's just how modern cars work, of course; you have to drive them to
>> get the temps up. Been that way for years and years.
>>
>> The clue was his claim that the temp needle never gets to the middle.
>> That's simply not true. When the engine is running properly, the body
>> computer will move the temperature needle to the middle to indicate "all
>> is well". It won't fluctuate up and down with minor variations. If the
>> needle is in fact not getting to the middle during normal driving, then
>> something is indeed wrong.
> I never warm the car up in the driveway, except to clear the windshield.
> I get in it and go, and expect when I hit the signal 1 mile away, I am
> getting some heat out of the vents, just like the other three cars I
> drive. It isn't happening on the Odyssey, until nearly the second mile.
>
> Tom
>
don't top post.
what temperature does the coolant read on the computer output?
==============================================================================
TOPIC: new Honda CR-V break in
http://groups.google.com/group/rec.autos.makers.honda/t/e22c4e2539b2b72e?hl=en
==============================================================================
== 1 of 13 ==
Date: Sat, Jan 23 2010 6:36 am
From: "E. Meyer"
On 1/21/10 12:31 AM, in article 2vS5n.2479$CM7.1688@newsfe04.iad, "Greg"
<nospam@null.net> wrote:
> A CR-V will not require anything super dooper. When buying, look for an
> "Oil Change Special" (oil + filter) at the local parts store and call it
> good!
>
A US Market CR-V requires 5W20 weight oil per the mfr. You're not likely to
find that at any "oil change special" unless its the Honda dealer. If you
run anything else in it, they could invalidate the warranty if there are any
oil related engine problems.
== 2 of 13 ==
Date: Sat, Jan 23 2010 6:57 am
From: "Guy"
On Sat, 23 Jan 2010 08:36:03 -0600, "E. Meyer" <e.p.meyer@verizon.net>
wrote:
>On 1/21/10 12:31 AM, in article 2vS5n.2479$CM7.1688@newsfe04.iad, "Greg"
><nospam@null.net> wrote:
>
>> A CR-V will not require anything super dooper. When buying, look for an
>> "Oil Change Special" (oil + filter) at the local parts store and call it
>> good!
>>
>
>A US Market CR-V requires 5W20 weight oil per the mfr. You're not likely to
>find that at any "oil change special" unless its the Honda dealer. If you
>run anything else in it, they could invalidate the warranty if there are any
>oil related engine problems.
Pardon me for asking a dumb question but does Mobil1 come in different
viscosities like 5W20, etc... ?
== 3 of 13 ==
Date: Sat, Jan 23 2010 7:11 am
From: jim beam
On 01/23/2010 06:57 AM, Guy wrote:
> On Sat, 23 Jan 2010 08:36:03 -0600, "E. Meyer"<e.p.meyer@verizon.net>
> wrote:
>
>> On 1/21/10 12:31 AM, in article 2vS5n.2479$CM7.1688@newsfe04.iad, "Greg"
>> <nospam@null.net> wrote:
>>
>>> A CR-V will not require anything super dooper. When buying, look for an
>>> "Oil Change Special" (oil + filter) at the local parts store and call it
>>> good!
>>>
>>
>> A US Market CR-V requires 5W20 weight oil per the mfr. You're not likely to
>> find that at any "oil change special" unless its the Honda dealer. If you
>> run anything else in it, they could invalidate the warranty if there are any
>> oil related engine problems.
>
>
> Pardon me for asking a dumb question but does Mobil1 come in different
> viscosities like 5W20, etc... ?
how about this for a dumb:
"is your browser broken? can't you get mobil1.com"?
ridiculous attention-seeking.
== 4 of 13 ==
Date: Sat, Jan 23 2010 8:32 am
From: jim <"sjedgingN0Sp"@m@mwt.net>
jim beam wrote:
> On 01/21/2010 01:47 PM, jim wrote:
>
> >
> > Are you really trying to argue that the exhaust can't flow through that
> > hole and dilute the gasses on the intake stroke???????
>
> look at the fucking valve dipshit - all those marks are for exiting gas,
> not entering. now, you go ahead and argue what you like to the
> contrary, but it'll just be ignorant idiotic bullshit.
Yes the damage was done when pressurized air blow torched through the valve. And
all of that happened as gas flowed out the cylinder. The rapid oxidation of the
iron in the valve produces tremendously high temperature so there is a runaway
reaction until the air that is feeding it reverses direction.
But after that event was over with, from then on gasses can flow in and out
the hole with very little effect to the valve because (after a few seconds of
cooling down) the valve is very much colder than normal.
>
>
> >
> >
> > If you had a hole that size in your exhaust manifold, do you think
> > exhaust gas would not flow through it?
>
> does you ass fill with water if it's downstream of a fire hose? how
> about if it's upstream? cos that burnt valve is upstream, just in case
> your powers of observation hadn't allowed you to determine the facts. [sic]
The normal behavior of exhaust system dynamics becomes kaput when you put a hole
that size in the exhaust valve. The hole doesn't need to be that big to disrupt
the proper functioning of the cylinder and exhaust. A good bit of the cylinder
pressure is going to be lost during compression stroke and by the time it gets
around to the exhaust stroke there aint that much left. You are pretending the
gasses pushed out during the exhaust stroke would have the same inertia they would
have if the cylinder was working properly.
The hole in that cylinder exhaust valve is downstream from the other exhaust
ports and the flow from that exhaust port is less than the exhaust from the other
ports so there is nothing stopping the flow from higher pressure areas to where
there is less pressure.
>
>
> > Do you think momentum and and the
> > fact that there is a bigger hole someplace else is going to keep the
> > exhaust gasses from going through the hole?
>
> see above.
Yeah right I'm supposed to look above at some dimwitted remark about you putting
fire hoses up your ass. You seem to be relying on an encyclopedic collection of
meaningless metaphors for your attempts to understand how the physical world works.
If there is a hole in the exhaust manifold there will be exhaust flowing in and
out of the hole due to the pulsating exhaust pressure. But much more gasses will be
flowing out than in because of the average internal pressure of the exhaust
manifold is higher than outside. That momentary low pressure that draws air into
the flow is what is referred to as scavenging . The hole in the valve won't be
much different than any other hole in the exhaust manifold.
>
>
> >
> > Do you think no one has ever measured the exhaust gas temps coming
> > from a cylinder with a burnt valve like that?
>
> of freakin' course!!! but it's low compression causing low power yield,
> and thus lower exit temps, not "exhaust dilution"!!!! jeepers - for a
> guy that was bleating about knowledge of the 4-stroke cycle, you sure
> are amazingly ignorant of it.
No that is incorrect. If a hole in the valve is small enough that the cylinder can
still support combustion a Exhaust Gas Temperature sensor will show on average
higher than normal temp, due flames leaking past the valve.
Regardless of whether you hold the opinion that the cylinder is producing
power or not, if the sensor shows the exhaust temps are cold the valve is not
going to erode or wear any more. At that point the cylinder has stabilized and the
valve remains unchanged thereafter.
>
>
> >
> >
> >
> >> no, it doesn't cut like steel does -
> >> valves have to be heat and oxidation resistant. thus they DO NOT
> >> INSTANTLY BURN IN A SHOWER OF SPARKS BECAUSE THERE IS NO OR LITTLE
> >> OXIDATION MECHANISM
> >
> > Except that isn't always the case. The mechanism that protects the
> > iron in the valve from rapid oxidation is an extremely thin surface
> > layer of chromium oxides.
>
> absolute bull fucking shit. you clearly know as much about valve
> metallurgy as you do about flow dynamics.
I know that if an exhaust valve does not have sufficient clearance it will get much
hotter than normal. And that can mean the valve will crack, fracture, warp or erode
away over time. But the end result of any of those scenarios will look much
different. And your feeble repetitions of the word "bullshit' doesn't change that
reality.
>
>
> > Under the right conditions that protective
> > layer can be destroyed and then the iron in the valve can rapidly
> > oxidize just as fast as mild steel.
>
> absolutely not. you're just guessing. and guessing wrong.
> bullshitting idiot.
Nobody saw what happened,. But we can be sure that your guess can not be
correct, because valves that burn slowly don't look like that. Valve
manufacturers have done extensive failure analysis. Based on that analysis, some
folk's guesses are more educated than others.
Small engine manufactures are a good source for information on this because
when a single cylinder engine is running along fine and abruptly stops running and
you open it up and find a valve that looks it has been flame cut with a torch there
is much less room for guessing as to what happened. Both Briggs and Kohler blame
this type of valve burnout on a chance encounter of combustion chamber carbon
deposits and the exhaust valve seat.
== 5 of 13 ==
Date: Sat, Jan 23 2010 9:52 am
From: jim beam
On 01/23/2010 08:32 AM, jim wrote:
>
>
> jim beam wrote:
>
>> On 01/21/2010 01:47 PM, jim wrote:
>>
>>>
>>> Are you really trying to argue that the exhaust can't flow through that
>>> hole and dilute the gasses on the intake stroke???????
>>
>> look at the fucking valve dipshit - all those marks are for exiting gas,
>> not entering. now, you go ahead and argue what you like to the
>> contrary, but it'll just be ignorant idiotic bullshit.
>
> Yes the damage was done when pressurized air blow torched through the valve. And
> all of that happened as gas flowed out the cylinder. The rapid oxidation of the
> iron in the valve produces tremendously high temperature so there is a runaway
> reaction until the air that is feeding it reverses direction.
for ordinary iron, oxidation is strongly exothermic, yes. but ordinary
iron is no good at corrosion or heat resistance, so what are valves made
of, dipshit?
>
> But after that event was over with, from then on gasses can flow in and out
> the hole with very little effect to the valve because (after a few seconds of
> cooling down) the valve is very much colder than normal.
but the freakin' gases aren't dipshit! besides, valves burn slowly -
see above.
>
>
>>
>>
>>>
>>>
>>> If you had a hole that size in your exhaust manifold, do you think
>>> exhaust gas would not flow through it?
>>
>> does you ass fill with water if it's downstream of a fire hose? how
>> about if it's upstream? cos that burnt valve is upstream, just in case
>> your powers of observation hadn't allowed you to determine the facts. [sic]
>
> The normal behavior of exhaust system dynamics becomes kaput when you put a hole
> that size in the exhaust valve.
so exhaust gasses are suddenly going to flood upstream - glad you could
re-write the entire book on flow dynamics and clear that up!
> The hole doesn't need to be that big to disrupt
> the proper functioning of the cylinder and exhaust.
really??!!!
> A good bit of the cylinder
> pressure is going to be lost during compression stroke and by the time it gets
> around to the exhaust stroke there aint that much left.
bravo. oh, btw, that's not "exhaust gas dilution".
> You are pretending the
> gasses pushed out during the exhaust stroke would have the same inertia they would
> have if the cylinder was working properly.
no, you are pretending that exhaust gas flows upstream!
> The hole in that cylinder exhaust valve is downstream from the other exhaust
> ports
eh? have you ever seen a honda manifold? you can't have to make a
statement like that.
> and the flow from that exhaust port is less than the exhaust from the other
> ports so there is nothing stopping the flow from higher pressure areas to where
> there is less pressure.
straw clutching drivel. what you /can/ get is a pressure wave, but that
is not exhaust flow. but you'd know that if you had the slightest clue.
>
>>
>>
>>> Do you think momentum and and the
>>> fact that there is a bigger hole someplace else is going to keep the
>>> exhaust gasses from going through the hole?
>>
>> see above.
>
> Yeah right I'm supposed to look above at some dimwitted remark about you putting
> fire hoses up your ass. You seem to be relying on an encyclopedic collection of
> meaningless metaphors for your attempts to understand how the physical world works.
>
> If there is a hole in the exhaust manifold there will be exhaust flowing in and
> out of the hole due to the pulsating exhaust pressure.
no, dipshit. does hydraulic fluid need to flow to transmit pressure???
of course not. neither does your phantom upstream flowing exhaust
gas. similarly, with a brake line, once you do get flow [open a bleed
valve], what happens to pressure???
[i blame [y]our education [system].]
> But much more gasses will be
> flowing out than in because of the average internal pressure of the exhaust
> manifold is higher than outside. That momentary low pressure that draws air into
> the flow is what is referred to as scavenging . The hole in the valve won't be
> much different than any other hole in the exhaust manifold.
except that a hole in the manifold is downstream, and an exhaust valve
is upstream!
>
>>
>>
>>>
>>> Do you think no one has ever measured the exhaust gas temps coming
>>> from a cylinder with a burnt valve like that?
>>
>> of freakin' course!!! but it's low compression causing low power yield,
>> and thus lower exit temps, not "exhaust dilution"!!!! jeepers - for a
>> guy that was bleating about knowledge of the 4-stroke cycle, you sure
>> are amazingly ignorant of it.
>
> No that is incorrect. If a hole in the valve is small enough that the cylinder can
> still support combustion a Exhaust Gas Temperature sensor will show on average
> higher than normal temp, due flames leaking past the valve.
bullshit. combustion temperature is a function of compression. as
compression decreases, so does combustion temp. basic thermodynamics.
>
> Regardless of whether you hold the opinion that the cylinder is producing
> power or not, if the sensor shows the exhaust temps are cold the valve is not
> going to erode or wear any more. At that point the cylinder has stabilized and the
> valve remains unchanged thereafter.
you are slowly getting there, except that it's not anywhere that simple.
at low exchange rates, i.e. low rpm, there is more time to establish
equilibrium, and thus tend towards zero pressure differential. however,
as rpm's increase, there isn't, thus combustion continues to occur, and
valves continue to burn for quite some time after symptoms first appear.
"stabilization" is long and slow, not "milliseconds" as you were
previously guessing.
>
>
>>
>>
>>>
>>>
>>>
>>>> no, it doesn't cut like steel does -
>>>> valves have to be heat and oxidation resistant. thus they DO NOT
>>>> INSTANTLY BURN IN A SHOWER OF SPARKS BECAUSE THERE IS NO OR LITTLE
>>>> OXIDATION MECHANISM
>>>
>>> Except that isn't always the case. The mechanism that protects the
>>> iron in the valve from rapid oxidation is an extremely thin surface
>>> layer of chromium oxides.
>>
>> absolute bull fucking shit. you clearly know as much about valve
>> metallurgy as you do about flow dynamics.
>
> I know that if an exhaust valve does not have sufficient clearance it will get much
> hotter than normal. And that can mean the valve will crack, fracture, warp or erode
> away over time.
cracking is almost unheard of. fracture is what happens after cracking.
warping is a function of temperature or loading - and warping is not a
factor in valve burn. erosion is caused by gas leakage due to failure
to close properly, or by a valve defect.
> But the end result of any of those scenarios will look much
> different. And your feeble repetitions of the word "bullshit' doesn't change that
> reality.
the "reality" that you clearly don't understand???
>
>
>
>>
>>
>>> Under the right conditions that protective
>>> layer can be destroyed and then the iron in the valve can rapidly
>>> oxidize just as fast as mild steel.
>>
>> absolutely not. you're just guessing. and guessing wrong.
>> bullshitting idiot.
>
> Nobody saw what happened,.
hey, you never saw that guy get shot, so that bullet hole didn't kill him!
or is the whole point of analysis to examine the physical evidence so
you /do/ know what happened??? [rhetorical]
> But we can be sure that your guess can not be
> correct, because valves that burn slowly don't look like that.
bullshit! dude, not only are you hopelessly undereducated on this stuff
[which would be curable if you weren't so closed], your problem is that
you refuse to learn, analyze, or even begin to seek out what it doesn't
know. thus, you're not merely ignorant, you're actually stoooopid.
> Valve
> manufacturers have done extensive failure analysis. Based on that analysis, some
> folk's guesses are more educated than others.
and some folk not only fiercely resist learning a damned thing, they
actually guess and bullshit, just for the sake of hearing their own voice!
>
> Small engine manufactures are a good source for information on this because
> when a single cylinder engine is running along fine and abruptly stops running and
> you open it up and find a valve that looks it has been flame cut with a torch there
> is much less room for guessing as to what happened. Both Briggs and Kohler blame
> this type of valve burnout on a chance encounter of combustion chamber carbon
> deposits and the exhaust valve seat.
briggs and kohler both have huge combustion technology and metallurgical
r&d facilities and make their own valves don't they. oh, wait, no they
don't... you don't work for one of them do you?
== 6 of 13 ==
Date: Sat, Jan 23 2010 10:35 am
From: jim <"sjedgingN0Sp"@m@mwt,net>
jim beam wrote:
>
> for ordinary iron, oxidation is strongly exothermic, yes. but ordinary
> iron is no good at corrosion or heat resistance, so what are valves made
> of, dipshit?
The reaction of the iron in exhaust valves with oxygen is every bit as
exothermic as the iron in mild steel. The alloys used in valves are
designed so that type of reaction normally can't happen, but your valve
is evidence that it does happen. Your valve can be easily cut with a
torch. Ask a welder to show you how.
== 7 of 13 ==
Date: Sat, Jan 23 2010 12:52 pm
From: "E. Meyer"
On 1/23/10 8:57 AM, in article uh3ml5tl90f3auv2t3nklcjh2pjrvjppov@4ax.com,
"Guy" <void@void.com> wrote:
> On Sat, 23 Jan 2010 08:36:03 -0600, "E. Meyer" <e.p.meyer@verizon.net>
> wrote:
>
>> On 1/21/10 12:31 AM, in article 2vS5n.2479$CM7.1688@newsfe04.iad, "Greg"
>> <nospam@null.net> wrote:
>>
>>> A CR-V will not require anything super dooper. When buying, look for an
>>> "Oil Change Special" (oil + filter) at the local parts store and call it
>>> good!
>>>
>>
>> A US Market CR-V requires 5W20 weight oil per the mfr. You're not likely to
>> find that at any "oil change special" unless its the Honda dealer. If you
>> run anything else in it, they could invalidate the warranty if there are any
>> oil related engine problems.
>
>
> Pardon me for asking a dumb question but does Mobil1 come in different
> viscosities like 5W20, etc... ?
Mobil 1 does come in 5W20. That's what I run in my CRV. For a long time
that was the only choice for that weight. Its starting to appear in other
brands now also.
== 8 of 13 ==
Date: Sat, Jan 23 2010 2:52 pm
From: jim beam
On 01/23/2010 10:35 AM, jim wrote:
>
>
> jim beam wrote:
>
>>
>> for ordinary iron, oxidation is strongly exothermic, yes. but ordinary
>> iron is no good at corrosion or heat resistance, so what are valves made
>> of, dipshit?
>
> The reaction of the iron in exhaust valves
/what/ iron in exhaust valves? you evidently didn't bother to read the
exhaust valve alloy cite i gave you. you still carefully snipped it though
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