Tired Old Man

My Feedback: (1)

Without a curve, almost nothing is gained from the 3/4 throttle point and up. If you have the linkage set up too far out on the servo arm and too close in on the carb, that little change point can be awful close to 1/2 throttle.

Rocky V.

My Feedback: (25)

A little off topic, I started my 110 for the first time over the weekend, was using an NX 26x10, Lawnboy ashless at 32/1. I only came in a little on the low end, but the idle was real rough. I am going to pull the plugs 2day and I imagine they will be pretty black. I guess the question is, should I be running maybe 40/1 as a start point ? I never made any full throttle pulls, but the transition got better as it warmed up. I have a good temp. gun (Exergen) and was getting a 40deg. difference between cylinders. The rear being cooler. The front was up to 195deg. at one point with the rear at around 150deg. It also was pretty hard to start. Could it be only 1 cylinder was firing ? This is my first twin, just don't want to make any mistakes. Thanks.

RTK

My Feedback: (1)

You have both cylinders firing. Don't worry about the temp difference at this point, after you finally have the engine broken in and tuned properly those numbers will become much closer.
Run the lawnboy at 32:1 for the first gallon or so then switch to a good synthetic.
Don't make any full pulls on the ground for more than a couple of seconds. Be sure to have good baffling and just go fly it.

Rocky V.

My Feedback: (25)

Thanks for the response,
I pulled the plugs and the front one was pretty black, the rear was a little wet with oil, but was clean other than that. I checked the ign., both plugs are sparking, gapped them to .22 , cleaned and re-installed. Do you think I should I try to come down on the bottom a little more ? It's really shaking the airframe.

RTK

My Feedback: (1)

Go ahead and lean the low a little, that should do it. One thing to remember when you lean or richen the low it will affect the high also.

Rocky V.

My Feedback: (25)

Right. I'll watch the transition as I go. Thanks for the help.

ronman

My Feedback: (6)

Hello I am flying my bme110 and I ahve about 4 houres on it.but lately It runs fine on the ground but in flight when I hover it it seems to get stuck on the midrange it takes about 5 secondes before it peaks.Any idea whats goin on ?

RTK

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Do you have good baffling??? Also try a carb plate or line into the fuse.
I just made some minor baffling changes and it runs cooler than before.

ronman

My Feedback: (6)

yes I have good buffling. Its been flying great until now, I cleaned the carb tonight there was some crap in it. I will test tomorrow and see if that helps.

RTK

My Feedback: (1)

That will do it.

danrc2

i have the bme 110 and i am having problems with the high end. the end has about 7 gallons through it now. the engine runs great for the first flight then the second flight the engine runs very bad. its poping alot and not getting up to full power and the engine was hot to touch. i then richened the high end then the engine ran better, but the transition from mid-range to full power is still very bad. at times it sounds like the engine is going to stall, never getting up to full power. i am going to pull the plugs in the morning. i hope the plugs tell me what the problem is. the low end to mid-range sounds good, just the high that is messed up.



anyone have any ideas. PLEASE HELP!!!!!!!!

danrc2

also what should the RPMs be for a 26x12 CF prop and also the temp. on it????

Tired Old Man

My Feedback: (1)

A 26-12 is not one of the better prop sizes for this engine unless you are looking to go fast. Go up to a 27-10. If the engine temps get above 325 shut it down. Much better to stay below 300. If you are running the engine up on the ground in an attempt to find the correct temperature via the carb needles then your engine will be dead meat in short order. Unless you have a live telemetry feed with high sample rates from the engine to a laptop you don't have a chance of accurately determining anything. Find peak rpm with the high needle and back off a couple of hundred. Peak the low needle and leave it there. make extremely minor adjustments as needed from there based on flight performance.

As far as rpm are concerned, that number will be determined solely by atmospheric conditions at the location you're flying at and the manner in which the engine has been tuned. No two engines are the same.

danrc2

so the best thing to do is to set the low end which it seems to be ok, the max the rpms on the high end the come down a hundred or so.

danrc2

the prop is a 3 bladed CF 26x12. the plane is low i realy cant go any bigger in size.

Tired Old Man

My Feedback: (1)

I don't have enough experience with 3 blade props to be of much help here. I'm thinking you may need to be in a 25" range but hopefully some others wil chime in here to help on that.

peak the low needle and the peak the high needle and back the high needle down a couple of hundred R's. Your ear will be enough, you really don't need a tach. From one of your earlier posts it sounds like you have the high end too lean, causing the engine to get pretty hot. What type of baffling, if any, do you have inside the cowl to direct the air through the cylinders and how much hot air exit area do you have? Baffles for good cooling on a twin are a matter of necessity, and not an option.

Rocky V.

My Feedback: (25)

Is a 26x10 3 blade a bit much ? I'm just asking because I am using a 26x10 2 blade for break-in to be followed by a 28x10 2 blade in another couple of gallons. Although I realize after 7 gallons yours is well seated, maybe it's an overload issue. Silversurfer will have a better idea on this...

danrc2

the plane is the H 9 suhkio. i bought it used. the guy the had it before me had the bme 110 in it and it ran great. so i bought a new engine for it because he took his out. so i know its not the plane with cooling and air flow. it has to be the high end needle setting.

RTK

My Feedback: (1)

The 110 carbueration (sp) can be tricky. There is a relationship between the high and the low that need to be met for this engine to run properly in the mid range.

This is the procedure I used on my 110.
Start with low out about 1.5 and high out about 2.5
Set the high and back off 1 or 2 hundred. Do Not hold at WOT for more than a couple of seconds, that is long enough. Allow sufficient cooling before re adjusting
Lean the low until it starts to hesitate when goosed. Then richen a little bit past the point where it does not hesitate when goosed. Always make sure not to over heat your engine on the ground.
Now, re set the high and back off a hundred or so.
If you follow this procedure you should only need minor tweaking when flying.
As mentioned before never run WOT on the ground for more than short bursts, allow to cool and always baffle well.

Antique

My Feedback: (4)

Hey RTK, did Keith switch to WGA carbs ?

RTK

My Feedback: (1)

Yes he did Ralph, WGA9 931 with a HUGE reed block. About 2 1/2 x 21/4 x 2

danrc2

the manual says to use a 26x12 3blade prop after break in. now after starting over back to factory settings i can not get and power out of the plane at all. when i removed the plugs they were black. say that i was too rich. i am really starting not to like this engine and get too the point were i would not recommond this engine to anyone very soon!!!!!!!!!!!!!!!!!!!!!!!!!!

someone tell me what i am doing wrong????

RTK

My Feedback: (1)

If the plugs are black it is to rich like you have stated. Slightly lean it and fly, repeat in small increments until you have it where you want it.

NuttyPro

I just realized something about this engine. Don't try to adjust the engine when it is still under the broken in process. Wait until at least 5-6 gallons (or more) of gas went through it. If one tried to adjust it while it is still not broken it, one will risk a chance of cooking the engine and it is is a very high probability. I know, the engine runs like **** without adjustment and 5-6 gallons of gas is a long time to wait for. Also, one need to replace the black rubber boot inside the ignition cap with the DA hight temperature boot. I guarantee that the stock rubber boot will melt and cause the engine to run terrible. I recommend replacing this boot from day 1. Also, one need a radio with the throttle curve option to make the engine response better like the JR10X. My engine have almost no response from idle to about 1/3 throttle (very little torque from the engine).
My setting is as below:
low - 3/4 turn (any lower than this the engine will quit)
high - slightly more than 1-1/4 turn.
I'm at sea level.
My engine seems to run OK now, but I still don't like it.