ChitownRC

Just want to make sure that's normal.... The brown/blackish crud on top is like built up on the piston, not burnt in or pitted.

Or is that too rich?

Looks like burnt eggs on a frying pan

Well the motor got nice and hot and I got hungry so...

to me it looks like you were running too lean, to rocco that's carbon build up from running too rich or not "clearing it out". Not talking for you roc, I just know that's what you think...lol

anything that is Burned (Black) in a RC motor, IMO, means it was too hot so it burned.

My Sirio .18's piston wasn't black after 8 gallons. My Ebp5 piston was light brown after 4-5 gallons. My blown 2.5's piston was black.

LOL!!! I was staying out of this one tex! LOL!

a little rich and what fuel? od? looks like castor burning more than most brands.

I say fire the thing up and lets have are own version of hells kitchen on that piston. I can make a mean omelet!

slim Wrote:a little rich and what fuel? od? looks like castor burning more than most brands.

****Cough** I agree *** Cough*** cough****

Looks a little rich...my $.02

Now I'm afraid to look inside my engines after using nothing but OD's....but I guess I better.

DAVEC-NITRO-RS4 Wrote:Now I'm afraid to look inside my engines after using nothing but OD's....but I guess I better.

OD is not bad fuel Dave... Dont be afraid:p:

I run 30% Byrons... If it's rich I'm ok with that, it's getting over 200* for sure.

Double post.

Ehh it could be from being to rich, or it could be from running to hot. It looks alot like carbon build up from running rich and not hitting peak rpm's to clean it out often enough, but all the ripples on the black looks kind of like pitting, so i'm not to sure on this one.
-Pete

Carbon build up in a motor that's had like 2 gallons on it? Comparred to a 1/1 car with, say, 50,000 miles on it?
I can see a real car building up carbon, they all do it. They drive thousands of miles and most people don't get on them hard enough frequently.

An RC engine is not a 1/1 engine and it's not driven the same way. I've seen Revo2K drive, he gives it all it has and then some.

My initial thought when I saw the pic was he ran rich for awhile, had lube build up, then ran it hot making the lube burn.

What makes burned black substance anyway? a cold, rich engine? The only way to burn things is give them too much heat.

Tex-

Lean or rich what happens thousands of times per minute inside our little engines....
A little fire ball explodes inside them! A fireball that is burning nitromethane! Nitro methane burns at over 800 degrees!
So why is it so hard to believe that a rich running engine cant have scorched oil on the pistion head??? Its only castor oil and im sure it breaks down at less than 800 degress..

Im just sayin that a rich engine can have depoists... Not trying to fight with you bro.. Just trying to have a conversation so please dont take this as me tryin to be a jerk

:banana:

C'mon !!!!! gimmie more that!

Tex Wrote::banana:

what? it's a pop/lock bannana stuck in lock mode

LOL! ok... I guess its peanut butter jelly time i guess!

rocco79 Wrote:LOL! ok... I guess its peanut butter jelly time i guess!

I guess that too! I guess...

haha.... J-F-W-Y

Sorry gabe....

sorry? forrrr???? 8^P

I dont know... You seemed pissed or somthing... I mean you went banana on me!

the build up is prolly buned oil......fro the fuel your using.......rub it off with some wd40 and run some trinity platinum for a whole gallon and then look at the piston i bet you its the fuels amount and type of oil used.