TFF

How are the 4 stroke conversion engines oiled? or do you have to keep everything pos G to use?

Thanks Tom

av8tor1977

My Feedback: (6)

The Honda GX engines can be safely mounted inverted. I believe the Fuji, Briggs & Stratton, and Ryobi need to be mounted heads up and operated with minimum negative G. Can anyone else verify?

AV8TOR

foamcut

My Feedback: (40)

A related series of questions might be useful here:

1) Can 4 stroke glow engines (OS, Enya, magnum, YS, etc...) be run inverted?
2) If the answer to #1 is yes due to the oil content of the fuel, can the same principle be applied to 4 stroke conversions?
3) If the answer to #2 above is yes, does it make a difference if the ignition/fuel mix is magneto (gas), gas / glow, or just glow (alcohol / oil)?

I'm really interested in the feedback on this one.

Thanks

Patxipt

1) yes
2) no
3) if two is applicable, (see below), ignition princicple should be indifferent

There are some 4 stroke strimmer engines that follow 2-stroke principles and use a gas/oil mix to provide lubing (Ryobi?). AFAIK, the Honda GX series (gx25;gx35) are the only 4-stroke engines with a "wet sump" (it's more dry sump principle) that can be placed in any position without any lubrication problem due to their patented lube system.

TFF

How does the Honda oiling work?

Patxipt

Think of it like a cake mixer
The oil is on a seperate reservoir, part of the crankcase. It has a sling inside that rotates with the crankshaft, thus misting the oil and distributing it to the engine moving parts by timed induction holes. it then returns to the reservoir.

See here:

http://www.honda-engines.com/mini.htm

TFF

Thanks; looks promising.

av8tor1977

My Feedback: (6)

I have a Honda four stroke that is slated to go on an SR Batteries giant Eindekker. I'm not too worried about the weight, as the airplane has a ton of wing area, and with that long tail I'm sure I can get it to balance ok. I am slightly worried about the power however. We'll see... but it will be a while as I haven't even started the project yet.

AV8TOR

captinjohn

Here is my four stroke engine I am going to place in a J-3 Cub or something simular. Going to fly easy with this one!!! Its a scale model of a Contnental Aircraft engine! Kavan K-50. P.S. Hi to a new friend..named Geroge. Best Regards Capt,n

Patxipt

My Honda GX-25 turns a 17x6 prop (cut down 18x6 G-Sonic) at 7500 rpm easily on the ground.

av8tor1977

My Feedback: (6)

That's a nice engine captain!!

Patxipt ... Have you done any modifications to your Honda engine?

AV8TOR

Patxipt

I have only opened up the main jet with a string from a steel bike cable, minimal difference, but it helped to sustain top rpm, as it used to bog down after some 10 seconds and I'm using no air filter at the present time. It's all stock other than that.

shaunmichaeljohnson

hey fransisco
i have a question about the nitro 4-strokes, yes a little O/T but can you help me?
i was wondering how the oil in the fuel get's from the crank case to the valve terain under the rocker cover???
oh, how does the oil get from, the fuel to the crank case anyway???
because isnt the crank case in 4-strokes sealed from the intake and carby unlike a 2-stroke.

and the sthil 4-mix 4-stroke can be run inverted.
shaun

Patxipt

That Sthil, as I mentioned above, uses a pre-mixed fuel, like a 2-stroke.

On regular model thumpers, the oil passes from the gap on the piston ring, which is bigger than normal to induce that blow-by. It then passes from the crankcase to the front housing and valve train via the inner crankshaft bearing or, when the bearings are sealed, thru a hole on the case or on the crankshaft. It's easy

shaunmichaeljohnson

ahhh so that's why most 4 strokes are ringed and NOT abc.
shaun