Using exhaust pressure with diesels is a no-no because the moisture fro
the exhaust pullutes the fuel and stops the engine. Glows are mor
tolerant of moisture but at least it shows that running exhaus
pressure -does- introduce fuel contaminants in one form or another.
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Cha
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Chas's Profile:
I've never known a diesel that would need exhaust pressure - have never seen
one fitted with the necessary nipple either.
Most of mine are capable of sucking fuel from a tank considerably lower than
the carburettor be that with a throttle or just a "simple" venturi.
Malcolm
The problem is that most American diesels are not sold as true diesels, but
are converted glow engines, which are equipped with muffler nipples and
oversized carbs.
I'm surprised that some eager entrepreneur hasn't offered some true diesels
at reasonable prices in the US. Something with carbs sized for R/C diesel
operation.
Ed Cregger
Snip>
Pity one of the hobby outlets doesn't import some - there are a number of
manufacturers in Europe and Australia - at least there used to be :-(
Malcolm
For a while we could buy the MVVS .15 Diesel at a good price. Due to
procrastination, I missed my opportunity to pick up two or three during a
$50 a piece sale. 8>(
Ed Cregger
Yes, diesels really suck! :-}
Mfgs will never put a "pressure" manifold on the exhaust outlet though
for the abovementioned contaminants reasoning. Irvine, for example
specifically forbid "pressure", although if you do need it the usua
method used to be a crankcase tap.
Let's not go through the "how do you pressurise something with a bi
hole in the back of it" routine!
Cha
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Cha
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Chas's Profile:
True diesels have a lot of draw, therefore do not need exhaust pressure in
order to run. In fact, those with throttle will not run well with exhaust
pressure added.
There are no American diesels, only conversion heads for glow engines. I
owned one. I now own two PAW (Progress Aero Works) diesels, and 0.49in^3
and a 0.60in^3. Both have twin ball bearings and great carburetors.
Compression and needle settings interact, and cause newcomers to be puzzled.
But, they will run even if way off the proper setting. I have never had one
die in the air. If I am way off on my settings the engine may slow down due
to overheat, but it won't quit.
PAW's are not American engines, but they have an American distributor who
also sells diesel fuels. There are other American manufacturers of diesel
fuels, but I would never buy another gallon from the one that makes the
diesel conversion heads.
The distributor I am speaking of is Eric Clutton, email
snipped-for-privacy@cafes.net. He is a fine person, with a small, but very
responsive business. You may run into him at a flying event sometime.
Eric is a fine man! He is always ready to help with advice, too, and i
responsible for a great series of "cartoon" aircraft dating back t
the early sixties (Kwod, Sharkface, Fishface, etc etc).
I was lucky enough to visit the PAW factory in Macclesfield this year
and the guys there were terrific. They even machined up a few 3 BA pro
retaining nuts for my DC Merlin (koff) engine which I just happened t
have with me (koff koff), on the venerable and hallowed lathes
Considering that this was a competitor's engine, I think that speak
volumes for the spirit of the enterprise.
It was always said that diesels couldn't throttle down well, even b
experts like the late Peter Chinn. PAW have pretty well nailed that on
dead.
Happy flicking!
Cha
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Cha
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Chas's Profile:
| Let's not go through the "how do you pressurise something with a big
| hole in the back of it" routine!
Actually, let's go into that routine.
It's really quite simple.
1) It's not a straight shot -- there's generally a baffle in the
muffler that helps ... muffle ... the sound. This baffle increases
the pressure inside the muffler and the backpressure into the engine.
2) and the overpressure at the nipple is very slight -- like maybe
1/10th of an atmosphere anyways.
You don't need much pressure to help push the fuel to the engine --
the 1/10th or so of an atmosphere is enough.
DC no longer make model engines so are hardly "competition".
I still have some DC engines - Merlin, Spitfire and Sabre but the PAW
equivalents deliver much more power IMO.
Gig Eifflander, PAW founder, used to do a rebore service for ANY make of
diesel engine - I remeber an add quoting 7/6 for a rebore on a ED Bee for
example.
Those were the days...
Malcolm
Well you can bugger me gently with a conrod, I swear if I said "Deat
is Final" there would be some clever geek to argue the shout. What i
your bloody problem?
I said "Considering that this was a competitor's engine...". Which i
was. Which was remarked upon by Paul Eifflander, in exactly thos
terms.
Why not brush up on your English comprehension before posting thes
pointless quibbles? Yes, I am pissed off, because this forum i
populated by and ruined by nitpicking binaries who incorrigibly siez
upon and adhere to the wrong end of the bloody stick. Get a life fo
Christ's sake.
Moderator you can ban me I no longer give a toss.
Cha
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Cha
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Chas's Profile:
I don't have any "problem". I did point out that the founder of PAW would
undertake repairs to ANY diesel engine. Since DC no longer makes engines and
PAW still does, DC is hardly a "competitor".
I'm surprised that
As a "native" English speaker for over 60 years, I have no need to "brush up
on my English comprehension".
I have a life, and was not "nit picking". I have engines from both makers,
and I thought that, in my post, I had indicated that PAW were superior
engines - particularly as they make throttled, silenced versions. I don't
remember ever seeing a throttle for a DC, and the after market "mufflers"
robbed the engines of much of their available power, in my experience. I
admit I may not have tuned the engine for best results after fitting said
muffler, but it did make a considerable difference to the performance.
If you don't "give a toss" why bother responding in such a vituperative
manner?
Malcolm
It is because you can't understand basic English yet you pick people u
on it.
I didn't say DC are competition to PAW. I know that DC are out of th
diesel model engine business.
I said that the DC Merlin "was a competitor's engine". Paul Eifflande
said this too; it is a fact.
DC were a competitor to PAW.
DC made the Merlin.
Ergo the DC Merlin was an engine made by the competitors of PAW.
IE., "it was a competitor's engine".
I responded in a vituperative manner because you mightily pissed m
off. I -do- give a toss about this.
I do not give a toss about being banned.
Which is exactly what I said in the first place.
You -do- need to brush up your comprehension of English; it is at th
Mr. Magoo level. I do agree that you probably speak it like a native
but sixty years is not too late.
Still pissed off
Cha
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Cha
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Chas's Profile:
PMFBI, but this is an unmoderated Usenet newsgroup. You *can't* be banned
from it. In fact, many people flee to the websites because they fear the
freedom.
PRose
This comment is what started the feud between you two, Chas and Malcolm. IMHO it was uncalled for, but the reaction that followed was also uncalled for. There must be some animosity brewing from a former conflict, because I see no reason to get so steamed.
Relax guys!
So who are those "moderator" guys who issue warning strikes, clos
threads, deem language unacceptable ....?
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Cha
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Chas's Profile:
No animosity Brian, just "camel's back" irritation (at least on m
part).
Look, I do apologise, but this Forum is a fantastic idea and it i
ruined by semantics and pedantry. I have been involved in countles
fueds over complete nonsense, because someone picks up on a pett
inflection or grammatical slip; very often, as in this case, th
original criticism is unfounded and in error, and is patentl
patronising. The only motive in making the post is to air some imagine
superiority in knowledge, and not to advance the knowledge base of th
Forum.
I was out of order but I had just had a bellyful. It is typical that
fellow diesel-flicker, the last type of bod that I should rant against
should be the recipient; for this I offer my regrets.
Cha
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Cha
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Chas's Profile:
Chas, If that is a sort of apology, I accept it gladly.
Like you, I had had a bellyful - not, I may add form Usenet, and over
reacted.
My apologies are also offered.
Malcolm
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