engine bearings

[novass468]

the inner crank bearing in my maxx keeps going out ,this has happend twice with two completely different engines , both pro-15s, the first motor lasted about 1/2 gallon of fuel and the second one about 6 tank fulls after it was broke-in . both engines ran very well and then just died ,when i removed the glow plug the element was crushed and had pieces of metal stuck to it ,so i removed the head and found some of the ball bearings on top of the piston. whats causeing this? any help would be great.

[foolio]

What fuel were you using? I can't answer your question, but same thing happened to me and quite a handful of other guys too in other sites. My suspicion is on either the high temp or lack of sufficient lubrication on the inner bearing. I was using 20% O'Donnell. The engine seems to run very hot with it. Even at 2 3/4 turns out from top end. I'm thinking to change fuel soon.

[novass468]

i have only used traxxas 20% top fuel,i have heard of some guys adding extra oil to their fuel ,is this a good idea? and if so what kind of oil should be used and how much? i also have a rustler that has 3 gallons of traxxas fuel run through it ,i haven't had to replace anything ,and i run the **** out of it .

[foolio]

Traxxas fuel is recommended by the manufacturer so there shouldn't be anything wrong with it. If you want to add Klotz 2 cycle oil. I heard your LHS should carry it. There is a link where you may find it helpful adding oil to your fuel. Go to http://www.nitrorc.com/ and read "Custom Fuel Blending Workshop". Hope this helps. I'm thinking to do the same. I'll be increasing the oil percentage to 18%-20%, but not anytime soon cuz it's raining here. If you do before I get around to it. Please keep me informed, I would like to know the results.

[Subaru]

Foolio: 18% is sufficiant enough for most engines so you don't have to increase the oil percentage.

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