p3arljam

My Feedback: (5)

I am installing my first gas engine and I have read in some posts to remove the idle screw what is the reason for doing this?

JohnB96041

Another safety issue. Need a on-off switch to the ignition on the airplane, on-off toggle switch on the transmitter, and full idle and idle trim to kill the engine. Remove the Idle Adjustment Screw.

p3arljam

My Feedback: (5)

I have a tech aero IBEC already installed was just curious why some people remove the screw and some don't.

tailskid

My Feedback: (34)

That adjustment screw doesn't do anything for our use....your choice to toss it or not. One of our guys didn't remove it and with the engine being cowled, we couldn't understand why his idle was so high - yep, the Idle Adjustment Screw was screwed in 'just a bit'

ahicks

My Feedback: (2)

We're talking about removing the idle speed screw, not the idle mixture adjustment screw, right?

With the engine speed controlled by a servo, there's absolutely no need for the idle speed screw. You'll be using the servo to adjust/control the throttle/idle speed. Not that screw.

marksp

My Feedback: (9)

IMHO, more important is removal of the throttle return spring. Very important on chain saws, but works against the throttle servo used in our application.

I remove/disable this spring on all my DLE engines.

Cheers

ahicks

My Feedback: (2)

The throttle return spring is a hot topic subject to a LOT of debate. Almost everyone though, all agree that removing the spring is a bad plan. Leaving it engaged vs. disabling (unhooking) it is where all the disagreement comes in.

Truckracer

My Feedback: (19)

And .... servos use so little power to pull or hold against the spring it isn't really an issue. Several people (including myself) have performed the tests and published the results in various forums. In my opinion, there are several valid reasons for just leaving the spring as supplied and few valid reasons for disconnecting it. Zero reasons for removing it. Removing it can cause long term damage to the carb as the throttle plate can wear into the carb body. On many carbs, the spring acts as a spacer to locate and control end play on the throttle shaft.

Years ago, I use to remove or disconnect springs until I saw the error of my ways. Now I just leave them as supplied.

marksp

My Feedback: (9)

Agree I should have been more clear; removal = disengaging, at least for me.

I suspect, if your linkage geometry is dialed, and you running a quality servo, then disengagement prolly not required. On smaller airframes appropriate for DLE20, many use less capable servos, so I've disengaged in this case.

YMMV

p3arljam

My Feedback: (5)

Thanks for all the help.

karolh

Got it from Ralph (Antique) some years ago that removing the spring is a bad idea as it helps to keep the carb's butterfly centered.

daveopam

My Feedback: (9)

I'm not going to end the throttle spring debate. I did however hook all of mine back up. At last years fly in I had a DLE30 powered 3DHS Edge 540 break the throttle linkage at about 40% power.( it's got 9 lives but that's another story) I did inside/outside loops for 20 minutes while it ran out of gas. I really thought it was going to come apart. Any build up of airspeed at that throttle setting would have fluttered the elev and cost me the airframe. Maybe this will start a ignition cut off debate, but if I loose linkage again I know the engine will die.

David

ahicks

My Feedback: (2)

That a hard learned lesson. That's generally how I learn as well....

karolh

Lessons learned the hard way tend to stick