Hello! Anyone home?

Originally Posted by JCFLYR

I am buying an airplane from a guy who runs 64:1 with Redline on a DLE-170. I want to run 40:1 with Stihl HP Ultra. Will I need to reajust the needles for the added oil in the 40:1 ratio? Thanks in advance, JC

You will have to adjust your needles.

Originally Posted by JCFLYR

I am buying an airplane from a guy who runs 64:1 with Redline on a DLE-170. I want to run 40:1 with Stihl HP Ultra. Will I need to reajust the needles for the added oil in the 40:1 ratio? Thanks in advance, JC

With EVERYTHING else being equal (assuming the previous owner's settings were "Spot/On".....& that may be a lot to assume).....yes, more oil =less fuel & will require a "Richer" adjustment......also you can make the argument that more oil creates a higher "Viscosity" blend with more resistance to flow......="Richer" adjustment.....FWIW.....

Great thanks guys!

hey guys......

i'm trying to tune my dle61....falcon 24x9

1. Full throttle......HS 'slightly' below peak rpm
2. Tune LS at 3500-4000 rpm.....
3. I get a smooth idle, a smooth transition and a got high end.....by smooth transition i mean literally a steady movement of the throttle stick from low to high

however, when i suddenly accelerate throttle, engine dies.....i've tried many different settings now including richening both needles......that messes everything else and yet doesn't help with the engine dying on sudden acceleration....

any suggestions???

sounds like you're a touch lean on the bottom.

Is your idle too low?

idle is 1800....I suspected LS was lean...

I've tried many different settings now....

nothing seems to be working....it.just dies when I throttle it suddenly.....

Even newer carbs can have issues.
Maybe check the screen, metering arm height, and diaphragm.

Originally Posted by bluefear

hey guys......

i'm trying to tune my dle61....falcon 24x9

1. Full throttle......HS 'slightly' below peak rpm
2. Tune LS at 3500-4000 rpm.....
3. I get a smooth idle, a smooth transition and a got high end.....by smooth transition i mean literally a steady movement of the throttle stick from low to high

however, when i suddenly accelerate throttle, engine dies.....i've tried many different settings now including richening both needles......that messes everything else and yet doesn't help with the engine dying on sudden acceleration....

any suggestions???

Low speed needle is lean, richen it 1/4 turn and try again.
The best way to set the low needle is the acceleration test from idle.
Snap the throttle open, and if it hesitates or gasps or dies it is too lean on the low needle. If it burbles when you snap open the throttle, and then finally speeds up after it clears out a bunch of excess fuel, then the low needle is too rich.

ZDZ40 - Walbro WT76a carb. Purchased in 2004.

1. Airplane was finished building in 2010. Engine started for first time. Ran great for seven flights.

2. Crashed plane Oct. 31, 2010.

3. March 2015 - after finally repairing airplane, ran engine for first time since 2010.

4. Ran great again.

5a - May 2015 - took plane to field and engine won't run right. Won't transition to high. Began playing with needles and got things all messed up. Barely idles, won't transition, just a complete mess.

5b - ignition battery fully charged and passes 1 amp load test with flying colors. Same fuel as March 2015 - no ethanol. In sealed container. Weather 20 degrees f warmer. Cowl on instead of off but what dif would that make? Cylinder head sticks out the bottom of cowl. Rear carb inside engine box in calm air.

6a - Ordered rebuild kit wondering if 4 1/2 years was long enough for things inside the carb to deteriorate. But why would it run in March and not May?

6b - When the kit arrives I will install, test, and update.

7. HELP!

Most likely a simple cleaning of the screen inside the carb will cure what ails it. Reset the needles though after doing this and start from square one.

I agree about the screen. Those things can look clean but be plated over with a clear film. Be sure it not only looks clean but that it will pass fuel. Sometimes they have to be replaced to regain proper operation.

Have you mixed oils? I've seen gumming do that

is it normal for fuel to spill out from the hole in the bottom of the carb during priming/flipping?