possible rear bearing change

[tonystevens]

hi everyone,

this is my first post on this site and possibly my first engine bearing change.I was flying this weekend practicing some backwards circuits when my os hyper leaned out,a lot! It was smoking it was that hot,it turned out to be a split clunk line.Anyway i caught an hours flying tonight and noticed a dull rattle that i haddnt noticed before,also the tail had developed a twitch that wasnt there before.Im almost sure its coming from the engine.my question is how do i get to the engine bearings to have a look and what should i be looking for as signs of bearing failiure?
any help is appreciated.

[tourerjim]

Sounds to me engine is poss too leaned out as engine gives a rattle noise when too lean.

[tonystevens]

I maybe jumping the gun then, needle is at about 1 1/4 turns out .Its not an obvious rattle but it has developed scince the weekend .the backplate felt about right on tonights flight but i did think it sounded a little lean though. on climbouts the engine was faltering slightly and was over revving at the top. Would this suggest a lean run?

[tourerjim]

I maybe jumping the gun then, needle is at about 1 1/4 turns out .Its not an obvious rattle but it has developed scince the weekend .the backplate felt about right on tonights flight but i did think it sounded a little lean though. on climbouts the engine was faltering slightly and was over revving at the top. Would this suggest a lean run?

What fuel are ya using, should be at least 20%

[tonystevens]

Wildcat 30 .still on my first gallon though after changing from Beckra 16

[jamiem]

to check the bearing requires dismantling almost entirely. you may just aswell change it if youve got that far tbh

[tonystevens]

i havent got that far yet but makes sense to change it anyway.Ill richen up on next flight and see how it sounds .Im probably looking too much into it but im expecting some sort of damage considering how hot it got .after 20 mins of resting in the pits the backplate was still about the temp you would expect when flying!

[tourerjim]

I would suggest 1.5 turns on 30% then try her again, adjust one click out at a time & then one click at a time back in but no less then 'screw being one turn out'.
once you've found the quirtest point of engine you may need to adjust the small screw but only a tiny bit clockwise to smooth out low revs then check engine temp.

[tonystevens]

My idle mix screw is at about one oclock now so it could be slightly too lean.it idles great though and revs increase in about 2 secs on pinch test.

[Steve]

Wildcat 30 .still on my first gallon though after changing from Beckra 16

When you change to a new fuel with a higher nitro content, you really should richen the main needle by half a turn, and then retune from there.

Higher nitro = richer needle settings.

[tonystevens]

Sounds to me engine is poss too leaned out as engine gives a rattle noise when too lean.

When you change to a new fuel with a higher nitro content, you really should richen the main needle by half a turn, and then retune from there.

Higher nitro = richer needle settings.

its sounding like im running too lean ,ill re-tune tommorrow evening and let you know.Helpfull replies, many thanks