new rotary engine trouble ?

On Sat, 25 Mar 2006 21:25:22 -0500, "Chas Hurst" >
wrote:

>
>"Ian Dalziel" > wrote in message
.. .
>> On Sat, 25 Mar 2006 16:22:56 -0500, "Chas Hurst" >
>> wrote:
>>
>>>
>>>"Conor" > wrote in message
.net...
>>>> In article >, Chas Hurst
>>>> says...
>>>>>
>>>>> "jw 1111" > wrote in message
>>>>> ...
>>>>> > Hi, i see tv ads for the mazda RX8 with the rotary engine. have
>>>>> > mazda
>>>>> > solved all the previous problems with this engine or is it still
>>>>> > trouble
>>>>> > awaiting?
>>>>>
>>>>> What problems were unsolved?
>>>>>
>>>> Apex seals and the rotor tips used to wear.
>>>
>>>The apex seal problem was solved in the early 70's. I never heard of rotor
>>>tip wear.
>>>
>>
>> Erm... Aren't the apex seals at the tips of the rotors?
>>
>They sure are, hence the name. But they are not the tip of the rotor.
>

<confused>

--

Ian D

Ian Dalziel wrote:
> On Sat, 25 Mar 2006 21:25:22 -0500, "Chas Hurst" >
> wrote:
>
>>
>> "Ian Dalziel" > wrote in message
>> ...
>>> On Sat, 25 Mar 2006 16:22:56 -0500, "Chas Hurst"
>>> > wrote:
>>>
>>>>
>>>> "Conor" > wrote in message
>>>> t...
>>>>> In article >, Chas
>>>>> Hurst says...
>>>>>>
>>>>>> "jw 1111" > wrote in message
>>>>>> ...
>>>>>>> Hi, i see tv ads for the mazda RX8 with the rotary engine. have
>>>>>>> mazda
>>>>>>> solved all the previous problems with this engine or is it still
>>>>>>> trouble
>>>>>>> awaiting?
>>>>>>
>>>>>> What problems were unsolved?
>>>>>>
>>>>> Apex seals and the rotor tips used to wear.
>>>>
>>>> The apex seal problem was solved in the early 70's. I never heard
>>>> of rotor tip wear.
>>>>
>>>
>>> Erm... Aren't the apex seals at the tips of the rotors?
>>>
>> They sure are, hence the name. But they are not the tip of the rotor.
>>
>
> <confused>

The rotor is the big solid bit of alloy in the middle.

The apex seals are attached to the end of the points, i.e. the rotor tips.
But they aren't the tip itself, just a bit of summat attached to make it
seal better.

More than most people are ever likely to want to know is here...

http://www.personal.utulsa.edu/~kenn...n/chapter7.pdf

(try about p15 of the PDF, p271 on the page for tip details)

"mrcheerful ." wrote:
>
> "Lin Chung" > wrote in message
> ...
> > John S wrote:
> >> jw 1111 wrote:
> >> > ...have mazda solved all the previous problems with this engine
> >> > or is it still trouble awaiting?
> >> Which problems are you talking about. I'm not aware of any
> >> problems with a rotary made in the last 25 years.
> >
> >
> >
> > Yes, the effective and durable gas seals at the three tips of the rotor
> > and
> > at the sides has been a major problem. This was so seemingly intractable
> > initially that the other car makers also in the race abandoned the
> > programme
> > very early leaving only Mazda to soldier on. After so many incarnations,
> > the trouble free period of a Wankel engine as we now have in the Mazda RX
> > series is at long last comparable to that of a modern conventional
> > combustion engine. But, it is a gas guzzler! 10 to 15mpg if I remember
> > correctly. THIS is the major issue at the moment. On the other hand, it
> > is
> > extraordinarily smooth and quiet running, unequaled by any conventional
> > engine design, even the V8 notwithstanding, for the generative motion is
> > rotatory instead of up and down then being converted to rotatory. Yes, I
> > have a dream, one day....
> >
> > --
> > Lin Chung
> > [Replace "the Water Margin" with "ntlworld" for e-mail].
> >
>
> I notice that the RX8 was only a tiny fraction of a second faster round the
> top gear track than a thirty year old lotus, so what is the point?

So? You don't drive flat out all the time, the RX8 is plenty fast for today's
roads. A modern road car is a compromise between many factors; RX8 is probably
easier to live with than a 30 year old Lotus. The point of this engine is
clearly the rotary smoothness.

It might as well be a two stroke with the oil it uses !!! we've got one
at work 16K on the clock and its had around 12 litres of extra oil !!!!
its driven by a woman (no offence) and it aint hammered
poor mpg as well

should have bought a crossfire !!

On Sun, 26 Mar 2006 09:49:09 GMT, "mrcheerful
.." > wrote:


>
>I notice that the RX8 was only a tiny fraction of a second faster round the
>top gear track than a thirty year old lotus, so what is the point?
>

I thought we were talking about engines, not cars. How well would the
Lotus engine do trying to haul around something as lardy as an RX8?

Cheers,

Colin.

In article >, Chas Hurst says...

> They sure are, hence the name. But they are not the tip of the rotor.
>
It could just be the Apex seals then.

--
Conor,

Same ****, different day.

In article >, PC Paul
says...
> Ian Dalziel wrote:
> > On Sat, 25 Mar 2006 21:25:22 -0500, "Chas Hurst" >
> > wrote:
> >
> >>
> >> "Ian Dalziel" > wrote in message
> >> ...
> >>> On Sat, 25 Mar 2006 16:22:56 -0500, "Chas Hurst"
> >>> > wrote:
> >>>
> >>>>
> >>>> "Conor" > wrote in message
> >>>> t...
> >>>>> In article >, Chas
> >>>>> Hurst says...
> >>>>>>
> >>>>>> "jw 1111" > wrote in message
> >>>>>> ...
> >>>>>>> Hi, i see tv ads for the mazda RX8 with the rotary engine. have
> >>>>>>> mazda
> >>>>>>> solved all the previous problems with this engine or is it still
> >>>>>>> trouble
> >>>>>>> awaiting?
> >>>>>>
> >>>>>> What problems were unsolved?
> >>>>>>
> >>>>> Apex seals and the rotor tips used to wear.
> >>>>
> >>>> The apex seal problem was solved in the early 70's. I never heard
> >>>> of rotor tip wear.
> >>>>
> >>>
> >>> Erm... Aren't the apex seals at the tips of the rotors?
> >>>
> >> They sure are, hence the name. But they are not the tip of the rotor.
> >>
> >
> > <confused>
>
> The rotor is the big solid bit of alloy in the middle.
>
> The apex seals are attached to the end of the points, i.e. the rotor tips.
> But they aren't the tip itself, just a bit of summat attached to make it
> seal better.
>
Ah, it's the Apex seals being referred to then.


--
Conor,

Same ****, different day.

In article >,
Paul Giverin > wrote:
> I prefer Sir Frank Whittle's approach to smooth running rotary engines
> although I concede it isn't practical for road vehicles.

Be great for tailgaters.

--
*I have my own little world - but it's OK...they know me here*

Dave Plowman London SW
To e-mail, change noise into sound.

The message >
from "Dave Plowman (News)" > contains these words:

> > I prefer Sir Frank Whittle's approach to smooth running rotary engines
> > although I concede it isn't practical for road vehicles.

> Be great for tailgaters.

Ha - now you can /really/ blow them away.

--
Skipweasel
Pay no attention to that man behind the curtain.

On Sun, 26 Mar 2006 08:35:34 +0100, "Tim Downie"
> wrote:

>John S. wrote:
>> jw 1111 wrote:
>>> Hi, i see tv ads for the mazda RX8 with the rotary engine. have
>>> mazda solved all the previous problems with this engine or is it
>>> still trouble awaiting?
>>
>> Which problems are you talking about. I'm not aware of any problems
>> with a rotary made in the last 25 years.
>
>Fuel consumption?
>
>Tim
>
Wow! Now I am beginning to understand why Mazda quit marketing the
rx-7 in the USA....a lot of misinformed people about the history of
the Mazda rotary engine program.

The first Mazda with a rotary introduced in the USA, I think was the
rx-3, and it did have a few problems relating to the apex seals and
cooling in general. I don't think any of the rx-7 rotaries inherited
these issues, in fact I understood that the intention of the initial
rx-7 USA debut was to demonstrate that all of the issues with the
rx-3&4 engines had been resolved in the new rx-7 rotaries.

Today the Mazda 13b and above series of rotaries is probably the most
sought after engine for use in homebuuilt aircraft, due to it's smooth
operation and overall reliability, as well as a better HP/Weight
advantage over most conventional engines.

I am glad they continued to have success with rotary powered vehicles
elsewhere around the globe. I would like to see them market the
"Cosmo" full size car which is in the Lexus/Infinity high end
competition in Japan and elsewhere.

I think the biggest problem with the Mazda rotaries is that they were
never able to successfully win over a skeptical USA market, in spite
of having resolved early technical issues long ago, in the pre rx-7
days. As is apparent in some of the comments from others in this
thread......IMHO, anyway. Joe.