Paul,
I have quite a bit of experience running the 13b on natural gas.
In fact Mazda built 13b natural gas engine blocks back in the '90's.
There are still some here in my state still brand new in boxes.
I just bought two. During testing when I worked at RPI the 13b
would run 8k -10k on the stock seals. With ceramic seals the
time doubled. The natural gas engines come with ceramic seals and
9.7 compression. Another interesting thing about the natural gas
engines is they run so clean that they have omitted the
trailing ignition. The rotor housings only have one spark plug
hole. And the oil metering is half of a gasoline 13b. So the
engine is equipt with two spark plug distributor and only two
line oil metering.
Back in the day we did a test in the field with the Idaho fish
and wildlife for an indian tribe raising salmon. They needed an
engine to pump water from the river into tanks where they would
raise the fish and then put them into the river. The engine had
to run for six week straight. The requirements where no engine
pollution, no noise, and no evidence left behind when job was
finished. The team parked the 13b on a trailer near the stream
with a belt drive running a pump. A propane take was delivered
to the area and feed the engine. The engine had an audible horn
and light to tell when it was time to add the oil. A local
indian tribe member parked a small trailer next to the engine
trailer and kept the engine topped off. Worked great. Maybe you
could pass this along to Danny Perterson.
Thanks,Skip Gorman
Who do you get ahold of to buy an engine and how much?
Dale Davies
Thanks for the info Skip,
I was out of pocket for a few days. Like Dale I am curious how I
can get ahold of one or more of these boxed engines. Next
question, what type of reduction unit should be used? Danny Petersen
I remember someone selling the ceramic apex seals for these on ebay
last year.
Ed Carver
I was watching Hot Rod TV on Speed Channel this evening. They were
talking about a liquid propane injection system that Mother's developed.
Looks interesting. They were building a dragster with it.
http://www.autoblog.com/2007/10/31/sema-2007-1-000-hp-propane-
chevelle-by-mothers/
You'll have to glue the URL back together. Check it out.
They said it was way better than the gaseous propane version.
Mark LaPierre
Not that big a deal to do. Size injectors for the new fuel volume. Works
better that methanol in a diesel as it wants to vapourize. Methanol wants to
cool the air before it vapourizes and ends up washing the cylinder walls. The
LPG or LNG is a gas at ambient air temps. LPG stays a liquid when colder than
-40, does not matter C or F because they are the same at that temp. LNG still
will turn to gas as it boils and condenses at -162C. One advantage of NG is
that its combustible limits in air are 5% to 15% which is a fairly narrow
range, very different than H2. The expansion during vapourization is a problem
should a tank be ruptured. LPG is similar in this respect. Calgary Alberta had
a school bus with kids running LPG rear ended a number of years ago. Many were
burned and killed due to the rapidly expanding gas cloud. Very tragic.
Dale Davies
Dale, my Dad has a fuel injected V6 Mitsubishi duel fuel. The LPG
system runs through the original injectors, has a modified chip and is
"claimed" to produce the same power and that "seems" to be correct but
we haven't dyno tested it. What do you reckon ? carb systems are down
on power a bit and consume fuel 1:1.1 LPG the price still makes it
cheaper. Always warey of claims made by people trying to sell you
their product. There is also a lot of different names for the same
product which helps to confuse the issue.
My sister-inlaw has a dedicated LPG V8 ute, the petrol (gasoline,
more confusion) system has been removed altogether, a real bitch if
you run out of fuel, I'll check exactly how that is set up, me brother
is a mechanic so should just take a quick call. Seems that what is new
to you guys, could be old tech here. We have always been paying more
for petroleum (gasoline) and have copius quantities of LPG. Petrol is
$1.50/ltr, LPG is anywhere from 60cents/ltr city to 90cents/ltr
country and not available at all in the bush, go figure. ALL taxi's
(cabs) use LPG Graeme Riley
That one was OK.
Paul Lamar
LNG requires much more pressure to contain it in liquid form at anything
greater than cryogenic temperatures resulting in a very heavy tank. LPG
uses much less pressure to remain liquid at much higher temperatures
relative to LNG and a much lighter tank.
LPG can be kept in liquid form at pressures that normal injectors and
fuel rails can handle where LNG must be vaporized and fed through a
carburetor.
LPG vaporizing in the intake manifold after being injected absorbs a
great deal of heat which causes the fuel air charge to be chilled to a
much lower temperature/much higher density than you get with gasoline.
You get more fuel/air into the combustion chamber with the denser
charge. The benefit is similar to several pounds of boost. There is
additional benefit in the greater temperature delta between the charge
temperature and the combustion temperature. Boyle's law works for you
in the intake side as well as the compression and expansion phase of the
combustion cycle resulting in greater efficiency.
LNG must be vaporized before being fed into the carburetor. Very little
of the chilling effect of vaporization takes place in the intake manifold.
Mark LaPierre
--
The Rotary Engine News Letter. Powered by Linux.
ACRE NL web site.
http://www.rotaryeng.net
You Tube key word PaulLamar2
Copyright 1998-2012 All world wide rights reserved.