Miketc

I have Zenoah G26 mounted in a Pitts S2B, what is the recommended break in oil mix. The manual states Mix Gas & 2-stroke oil at a mixing ratio of 25-40:1
I ran the MVVS 35 on 33:1 for break in. Can I use the same mix? I plan to use a 18x6 Mejzelik carbon prop. Is it ok to run in on the ground for, say two tanks (650 Ml) then commit to flight?

Thanks in advance

Mike

Antique

My Feedback: (4)

The manual also states
"No specific break in is required,
the engine is gradually broken-in as it is used the the output is also gradually increased"
Only reason to run it on the ground is to get familiar with the carb settings.
More oil makes more power, 33:1 will be fine..
Pennzoil Air Cooled 2 stroke oil is great stuff, and inexpensive...

Miketc

Thanks for the quick response RCIGN1. 33:1 it will be. I have some Polaris (synthetic) Racing 2 stroke oil for my MVVS engines. Do you know the stuff? I was planning to use this..

Mike

RTK

My Feedback: (1)

Any good quality oil mixed at manufacturers recommendation will be fine. As Ralph has stated more oil=more power, find an oil in a mix ratio around 32:1 but no leaner than 50:1

soarrich

My Feedback: (98)

Is that right? If so why, it's counter intuitive.

RTK

My Feedback: (1)

Better sealing of the rings, more lubrication especially at higher temps. Ralph (RCIGN1) has done testing on this, Pe also posted a motorcycle article that had done the same testing and I "think" 15:1 produced the most power, but don't quote me.
After reading what the people in the know have said, I never felt it necessary to re-test. I have run a few different oils and none have ever failed me. The thinest I have gone was Amsoil 100:1 run at about 70-80:1.

Birddog-RCU

My Feedback: (62)

Have fun with that engine airframe combination. It is a great flying machine when powered but if the engine ever quits keep a very steep glide angle until you flair or it will slow down quickly and stall. Don't ask me how I know [:@]

lucien

Doesn't make sense to me either. Oil doesn't produce the power, the gas does. A friend of mine used to run a g23 in his xcell heli and after a lot of experimentation he ended up at 50:1 for the best results....

Also, I don't understand how most gassers don't require a specific breakin. My big gasser did when it was new and it was the most nerve-wracking 77 minutes of my life with the plane tied to the back of my truck.

Perhaps the manufacturers run the motors at the factory?

LS

Birddog-RCU

My Feedback: (62)

No one said they are already broken in. You just don't have to do anything special during break in except for following instructions. Put the engine on your plane and fly it.

More oil (up to a point as too much will foul plugs) = better lubrication and cooling which produces more power.

Balsa Steel

My Feedback: (3)

From "that" thread:

Antique

My Feedback: (4)

Been preaching this for years, should be required reading for all the people who believe the conventional "wisdom" that says less oil makes more power...Say anything long enough with enough conviction and it becomes reality...
As in "overweight underpowered boat anchor"

Birddog-RCU

My Feedback: (62)

Wait... that sounds like a liberal tactic. Meaning liberal amonts of oil that is least I start a political thread war LOL

Balsa Steel

My Feedback: (3)

That's "Hillaryous"

Birddog-RCU

My Feedback: (62)

Heh heh...

Miketc

Thanks for the advice Alan, I will keep the motor running....

Mike

karolh

I just love it when you guys talk drity

Karol

soarrich

My Feedback: (98)

I read that article. First it seems old, the changes in technology in the last 30 years is great. If this article still hold true, do you want an airplane with 15 to 1 oil? If you do OS Saito Super Tigre make engines just for you. I'm a sailplaner at heart, but I fly power too, but the thing that turns me off is the slim factor, which is what got me into gassers, low on the slim scale. If you run 15 to 1 oil I think you move to the front of the slim class, I think I'll check out that 100 to 1 oil.

Flamesuit on.

Birddog-RCU

My Feedback: (62)

No flame suit needed here. You just don't get to take advantage of the good advice offered is all. I think the point is an engine does not run better if it has less oil and more gas. I think we all agree that we don't like slime and that there is a point of diminishing returns where too much oil could just not work well and foul the plug(s).

Balsa Steel

My Feedback: (3)

In spite of the advancement in oil technology in the past 30 years, more oil in the gas still seals the rings better. I personally don't know any gasser flyers using, or recommending a 15:1 mix. (although testing does prove it makes more power)

Antique

My Feedback: (4)

We use it in our racing twins...Leaves two nice long black streaks on the top of the fuse from the end of the open pipe all the way back...Never stuck a piston...
Same McCoy #9 glow plugs lasted two racing seasons, never changed...