jackalope54

My Feedback: (2)

I bought a used 110S that I rebuilt - new gaskets, o-rings, regulator diaphragm, front and rear main bearings, new piston and ring and new cylinder assembly (piston and cylinder were scored). Running Byron 20/20 fuel (synthetic oil). Engine compression improved as the ring seated (have run about 1.5 gal), tank pressure is good and holds pressure for extended period, idle is 1800-1900 rpm, 15X6 APC prop turning about 9700, clean transition with regulator adjusted about 1/2 to 3/4 turn in from flush.

Engine will NOT prime when cold or after a dead stick from running out of fuel (ran out of fuel when breaking it in a couple of times - was flying when it happened). Engine WILL prime if I richen the regulator to the point that the transition is very rich.

Any thoughts?

Also - regulator seems VERY sensitive - 1/16 turn richer from current setting is too rich - burbles, stumbles in transition and high end is very rich.

Thanks in advance!

ThumbSkull

My Feedback: (57)

My 110 runs a 16x6 nearly that fast. If I had to guess from the description, the low end is probably a little rich and the high speed is probably too rich and the regulator is too lean.

Flush out the regulator with fuel.
Reset regulator to flush with the housing, then adjust the HS to just under top RPM, then set LS leaner by 1/8 turn at a time till it dies when you nail the throttle after a 20 second idle.
See how the transition is after this. Use an OS F or Saito plug.

Zeeb

My Feedback: (41)

Sounds like a good hypothesis as the regulator 'oughta be real close to even with the housing, only thing I'd add is that the little beasts are sensitive when you get close on the needles and I only turn 'em about a screwdriver blade width when I get close rather than 1/8.

ThumbSkull

My Feedback: (57)

If the regulator needs to be more than 1/2 turn from flush, the diaphragm/plunger should be replaced.

petec

My Feedback: (58)

He said in the original post that the diaphragm was replaced.

I am wondering if the regulator spring was replaced as if that was stretched or compressed the regulator will not function properly.

jackalope54

My Feedback: (2)

Thanks for the responses!

Already tried setting the regulator screw flush - way too rich. Poor transition and excessive fuel consumption - literally 16 oz in less than 6 minutes flying - had to set the timer on my transmitter to 5 minutes to prevent dead stick.

This is the "S" model - I remember Troy stating these usually required the regulator be adjusted 1/2 to 1 1/4 turn in from flush. Engine runs like a top at current settings with reasonable fuel consumption.

I'm going to order a new plunger, spring and the plastic end for the plunger and see if that makes a difference. It's almost like the plunger is sticking or the spring is too stiff or is stretched.

Will let you know how it turns out.

Thanks again for the help.