hardtop351

i think to get a more correct comparision between fuel efficency and consumption you need to setup 2 engines of the same make and model and run a different fuel in each. comparing a petrol engine to one that was originally designed to use methanol is not a true reflection....well to me anyways.

i have recently purchased a larger walbro carb to try on my engine. this carb has no choke plate nor does it have the small brass main jet protruding into the venturi. it does have a larger venturi (in diameter) and so will pass more fuel ( i hope)...all the better for alcohol fuel!! lol.

cheers
craig

flapper

Ok, I think I see where you are coming from. Same engine but different fuel. The consumption rate for the alcohol fueled engine would have to be considerably less than the petrol fueled engine to get any financial benefit. I suppose it would come down to the set up of the carby and the metering of the fuel.

linkadrip

Hmmm i would think the consumtion rate would be more for alcohol fueled engine then petrol since alcohol has a lower btu rating. So the bigger carb will meter more fuel into the engine to get the same benefit as the petrol fueled engine.

and so i can see the reasoning behind putting a bigger carb on the engine to get the same power output as the peterol engine.

The Raven

As a rough order of magnitude, methanol engines generally consume fuel at twice the rate of gasoline engines.

If you convert a gasser to run straight glow fuel you'll have to tune for a very rich mix (compared to gasoline). However, if you go for a mix of glow and gasoline (as one guy in our club does) you will get a compromise of better idle and overall fuel consumption. The main advantage is the removal of the entire ignition system.

I may try this with one of my spare engines but it's unlikely to make me a convert.

Remember, most Walbros setup for gasoline will handle 10% alcohol based fuels but if you go towards higher alcohol contents you will need to regasket accordingly. As already pointed an all alcohol burning engine will probably need larger jetting (not necessarily carb size itself).

hardtop351

im just wondering what gaskets you would use if you needed to "regasket" as you say raven. as all walbro and generic derivitives are made from the same materials as the original as a general rule. i have proven to myself that the idea of methanol "eating" gaskets/ carb bodies is noting more than a myth. as previously stated i run a 40:1 methanol mix....no other additives are used. ive NEVER had any problems with my carb or any gasket within.

the idea of mixing a mineral based fuel with an alcohol based fuel isnt a good idea. as both fuels will separate out with the mineral based fuel settling to the bottom.

walbro carbs have a wide tuning range with the twin needle setup. my setup required a further 1/2 turn rich from where it was set with the mineral based fuel.

with a walbro carb you can drill out the main jet all you like to allow more fuel to pass through.....but what about all the other fuel passages inside the carb body??.....what about the metering needle and seat??......it would be a very difficult job to enlarge all these passages as well just to keep up with the main jet.

the idea of using alcohol fuel in the first place was to get away from the main cause of my radio gear problems.....the ignition module itself was creating that much interferrence it cut through a jr pcm reciever. once i had all the conversion done i wasn't even sure that it would work let alone be reliable.

all i can say is that yes i have proven it works...and very well at that. and so to this end im as happy as a pig in ****. i've forgotten all the crap about the knockers and those thay say "it wont work". my engine works fine and very well and im not gunna change a thing.

cheers
craig

boex

I want to buy the DL 50 but it is not available down here in Argentina at the moment. What is available is the CRRC-PRO 45. Since this is a very long thread could someone please summarize the good, the bad and the ugly about this engine. Many thanks in advance.

The Raven

For those who disbelieve Walbro has alternative gasket sets to suit different fuels, I refer you to the bottom of page 4 of the Walbro Service Manual. They clearly identify the standard gaskets as being suitable for 10% ethanol and 5% methanol. For fuels exceeding those amounts a brown colored woven fibreglass diagphram is applicable.

[link=http://wind-drifter.com/technical/WalbroServiceManual.pdf]Walbro Service Manual[/link]

As to whether it's a myth, no-one can completely discredit it as long as one or more people have experienced it first hand. Such failures are obviously influenced by a number of factors (climate, fuel blend, storage etc) and some people may be just lucky to avoid it occuring.

wiz310

I so far have not had any trouble with my walbro carb. I run the same fuel as Hardtop351, and have done so for over 12 months now. no corrosion in the carb or problems with the gaskets or diaphragms. I never rejetted the carb and it was about one turn richer than the petrol set up. I might also add that the engine runs cooler, and uses only slightly more fuel than my DZY 48 twin on petrol. It hauls my 1/3 scale christen eagle around the sky with plenty to spare. The conversion has been the best thing I could have done to this engine in my opinion.

The Raven

Hi guys, I'm glad your conversions are working well. Please don't take my comments as 'you must use special diagphrams' etc in your walbros but consider it more as something to keep an eye on. I'm into various conversions and wierd setups but do take care to assess the risks of these mods. Fuel modifications are just one thing that falls into this category.

Fuel blends vary widely around the world and from season to season. Some people may never have problems but others will. It's just a case of being aware and keeping an eye out for problems. None of us want to lose a plane due to an avoidable failure.

I still have to dismantle my gasser and do a post crash inspection. This crash was a good example of an 'avoidable failure'. I did some repairs and a thourough pre-flight inspection but missed one simple check....that the servo leads were seated fully in the Receiver (I checked the servo extension connectors though...). End result was discovering that the plane won't fly with one aileron...when the other is locked solid due to the lead vibrating out.

psantaana

Hi:

It is available In Argentina. Look at this site:
http://www.rcjuampa.com.ar/product_i...e33bd70f0397df

It is more expensive than the CRRC GF45i (465 U$S vs 343 U$S):
http://www.rcjuampa.com.ar/product_i...e33bd70f0397df
http://www.luppomodel.com/

I have a GF45i and it's running good so far. I have an Edge 540T 28% from CAModel (6.6 kg).

Good luck...

Pablo.

PD: You can also visit www.aeromodelismoafull.com.ar (and its forum) and the Argentine forum in RCGroups: http://www.rcgroups.com/argentina-340/

boex

Thanks for the links Pablo. I already visited RCjuampa and when I added the DL-50 to the shopping cart it said item out of stock (no disponible), oh well. How does the GF45i pull that plane around? Does it have unlimited vertical? I'm also considering buying the same exact plane that you have. I think it looks awesome. I intend to do IMAC and 3d with it. Thanks again.

Don M.

My Feedback: (5)

Holy Crap ! Is that price in USA dollars $1490.00 [X(] Who gets the extra $1000.00 +

How much is a DA 50 ????

psantaana

No!!! That price is in Argentine pesos. In dolars: 465 U$S (DL50) and 343 U$S (GF45i).

1 U$S = 3.2 Pesos

Pablo.

Don M.

My Feedback: (5)

Good thing I was looking for my heart medication

psantaana

Hi:

I finished the plane a month ago. While I was building the plane I put 4 lts. of fuel (20:1) for break in with de engine in a bench. After that I used a 30:1 fuel for the last break in period and now I will use 40:1 with syntetic oil.

Marcelo Colombo flew my plane using a 20x8 TopFlite prop last week and he was doing some 3D manouvers like torque roll, etc. and the plane was doing well. I'm not a great pilot, just a sport one but I think it is a good combination.

I think that after the break in I should lean a bit the high end needle and put a 20x10 prop. The problem is that the made in Argentina props are not as efficient as the most popular ones (like Menz) but are cheaper.

Pablo.

boex

We pay more for the same dang engine in Argentina than you guys pay in the north, that is if you can find it and don't even talk about customer support. What's that?. Well, it's called La Revolucion! I love it, holy crap.[:@]

psantaana

Here are a couple of photos.

Pablo.

boex

Wow, she sure looks pretty. This is the one thing in Argentina that we can get at good prices, Colombo Anderson planes. They look great and they fly even better. I am getting one of those puppies as soon as I get the engine.

Great color scheme there Pablo.

psantaana

Thank you. I build it from the kit. I used Monokote for covering and made the design "inspired" by several other planes seen in the web. Form example, the bottom looks like the QQ Yak 54 (Big Red and White straps).

spitmad

Guys

Does this engine have the carby on the left or the right of the engine (when looking from the front at an inverted installation)

It seems that there may be left and right carbies ...............or is this some pics being loaded as mirror image ???


From the pics below which one is the real config ?


The other question is can the cylinder head be turned 180 deg to move the carby/exhaust to the oposite side (assuming that the ports are symetrical)

cheers

Alan

linkadrip

Well mine looks like the first picture of the engine. and if i were to take a picture of my plane the carb would still be sticking out the same side. the picture of the plane in the vehicle i have no clue why it shows the exahust on the carb side unless the picture had been changed like you said a mirror.

But if you take a closer look i dont thing that the picture of the engine is the same plane it looks like the engine picture is on a blue plane and the one in the car is yellow.

And the bolt pattern on the prop mounting of the engine pic has 4 bolts and the one in the car only has one bolt to hold the prop on so clearly ther not the same engines.

size*b

Hi Alan.
Q1. I think that the motor in the yellow model is the latest version, V3. I could be wrong, but it could be explained somewhere in this thread. ( If you have a spare life time to go through it ). :-)
Q2. I seem to recall that they are no able to be rotated due to port alignment probs etc. Maybe someone else can explain why in more detail.

Hope this helps.

Bernie.

Ace Radio Controlled Models

Hello I can help with this issue

version 1 + 2 both had the carby on the oposite side to the one in the picture ( yellow plane )

version 3 With box style muffler was turned 180 Deg to version 1 + 2

regards Scott

boex

The picture of the plane in the car couldn't be a mirror image cause the steering wheel is on the left hand side. All cars in Argentina come with the steering wheel on the left.

The Raven

There are several versions with, I think, the 'version 3' have the carb and exhaust swapped around. On my engine I wondered if the cylinder barrel could be turned 180 degrees so as to give a choice of two possible locations. Unfortunately, the crankcase to cylinder porting (specifically the transfer ports) do not match up. Someone may make that work, with some fiddling, but I doubt the engine would run as well as originally intended.