Engine help!!!

[Rushy36]

This engine is a hpi k4.6..it has had 1.5gallons of 20% and 3 more of 30% thru it.....i was wondering if everything looked ok becuase the top of the piston is black and edges are bronzeish colour.....

 

[Jeremy]

WOW.. looks bad bud.. ran lean ????

I thiink it's was ran REALLY HOT look at the color of the head fins .. even them are showing sings of a hot engine ...

I have had engines w/ over 6 gallons on them that looked 10times better then that one .. damn

How does it run ?

 

[Rushy36]

it runs nice..little trouble at low end....but its just dirt on the fins

 

[X]

I agree it looks like its been running pretty hot. You have to keep all the dirt and grime off the engine or it will run alot hotter.

 

[BIGDAN89]

looks like it ran lean what plug and fule are you running?

 

[Rushy36]

i run losi nitrotane 30% race formula and a O.S #8 plug

 

[Shaun]

wow that looks like it was torched lol i would have to agree I'm thinking its been ran to hot or lean as well!!

 

[BIGDAN89]

try going to a colder plug for the 30% race it will work way better

 

[Jeremy]

it runs nice..little trouble at low end....but its just dirt on the fins

ahhh Dirt wouldn't turn the fins pink.. purple to pink .... HOT !!!!

 

[Double-O-Zilch]

What temp was it running at? You may want to check the front bearing for leaks while you're at it.

 

[Rushy36]

how would i test it for leaks...this is my first time taking apart my engine...and it has been running around 230-245

 

[Rushy36]

and with it looking like it is what would be ur suggestions....fix the problems with piston and all....or new motor

 

[Jeremy]

I would take a dermal to it polish it up and try to clean some of the stuff up .. run it tell it dies .. the bearings is what you really need to be concerned about .. can't clean them up .. and if you do rebuild then you will want to get new bearings piston/sleeve... really not worth it IMO


Just try to polish and clean the stuff up run it till it dies and move on little buddy

 

[Rushy36]

ok..i will do that then...i think will i have the motor apart i will replace the bearing jus to be safe

 

[AB Mods]

If your going to clean the piston off make sure not to use anything abrasive as you don't want to remove any material off the edge of the piston... You don't want to rub it down at all.. as thats where ur seal is... Just use a tooth brush and some soap. Rinse it really good, relube and you should be good to go.

 

[Rushy36]

thanks for the advice..so what type of bit would u sugest? like a polishing bit?

 

[AB Mods]

If your asking me.. I wouldnt use a polishing bit on the piston .. for the simple reason as you could slip and hit the side of the piston where it gets its seal from..... Thats why i suggest using a soft tooth brush. And everyone has a tooth brush laying around... I hope!! :Xfingers:

 

[Rushy36]

i have a draw full of them in my box :FarleyParty:

 

[AB Mods]

Well heck yea there ya go! Ok I'll dance with you now.. :FarleyParty: LOL!! Love that smiley!!

 

[Crash]

If your asking me.. I wouldnt use a polishing bit on the piston .. for the simple reason as you could slip and hit the side of the piston where it gets its seal from..... Thats why i suggest using a soft tooth brush. And everyone has a tooth brush laying around... I hope!! :Xfingers:

Great to have ya around.

You are a nitro guru for sure!

:FarleyParty:

 

[Jeremy]

I was thinking of a buffering wheel ..

 

[AB Mods]

That would be a big no no... :FarleyParty:

 

[Jeremy]

works for me .. love the buffereing wheel on my bench grinder

http://www.sears.com/shc/s/p_10153_...Grinder&psid=FROOGLE01&sid=IDx20070921x00003a

 

[Rushy36]

I'm jus gonna use the toothbrush and soap...don't wonna screw it up cus i don't have funds for a new motor at the min.....and sorry for all the questions, ive never done this before....what type is the frontend bearing, and what size would it be......its on a hpi k4.6