RCbamm

My Feedback: (10)

hey peoples!

I bought a YS 91AC engine from a clubmember that I am going to be using in my Hanger 9 Spitfire. I have a few questions about this engine.

Question #1: This engine has a funny looking piece that is sandwitched between the regulator housing and the bottom of the engine case (see pictures) what is it and what does it do? It's not stock thats for sure.
Question #2: From looking at the stock engine diagrams, there is supposed to be 4 nipples total on the engine. There is only two coming out of mine and where the other 2 are supposed to go they are pluged with a scew (see pictures). I'm guessing that funny looking piece replaced the nipples with the piece's own nipples coming out the side of it (see pictures)
Question #3: What prop would be best for performance and fastest speed? I want this thing to be fast .

Any help will be appriciated!

EDIT: I just read somewhere on the internet that if you screw the diaphram screw to tight it will mess up the diaphram... I did scew the diaphram screw untill it stoped and didn't go any farther or didn't put any hard torque on it. I just wanted to count how many turns out it was. did I scew up my diaphram?

Thanks!

-Dan

w8ye

My Feedback: (16)

I ran a 14-10 on my Y-S 91AC

They are using the white plastic device as a fuel metering device rather than through the crankshaft

Run this engine on the bench first to verify operation and become accustomed to it.

RCbamm

My Feedback: (10)

Do you think I ruined my regulator?

w8ye

My Feedback: (16)

Most likely not. The standard setting for the regulator screw is flush with the case

David Bathe

I would just send in the engine for a complete strip down service.