Oh man, this gets even better - the border guys have just told me that my servos were sent on Friday - should be here any day now :D

Re: Re: Re: max engine
 

Yeah... too lean is not good at all. What I can tell you is that you may need to replace the Piston and sleav and check all the bearings, and also personally, I would change the head button, but that is my personal preference. I feel for you, it is an expensive lesson...

new engine?
 

take a look at this is this bad?

new engine
 

and this?

Re: Re: Re: Re: max engine
 

Thanks BaxterC im felling pretty down about this oh well life goes on

Re: new engine?
 

Is that piston coming out from the sleeve from the bottom side up? :eek: When you try to push the piston from the bottom of the sleeve, are you able to push the piston to come out fully?

Hard to tell the surface but it looks like the engine overheated. What fuel did you use? The black carbon deposits are burned castor oil.

Like AMGRacer said, clean the piston with a polishing compound to take off the black stuff on it. Check the piston surface if you can get to polish the surface to mirror finish. If not, then your piston experienced pre-detonation.

Re: Re: new engine?
 

No i just rested the piston on the sleeve i tried pushing the piston up trough it gets about halfway and then jams and i cannot move it any more and im using 16% fuel and hot glow plug

Re: Re: Re: Re: Re: max engine
 

Dont, It happens to all of us, I fried two motors before, one was too lean, and the airfilter kept falling off when I was in the dirt... NOT GOOD FOR ENGINE... I also overheated it permanently, I also didnt have a pipe from the tank to the pipe... the Second one, I rebuilt and got dirt in the main bearing, the bearing siezed, but somehow it managed to keep going, little did I know... this overheated the crank and siezed the bottom end bearing... SNAP went the Conrod (to the tune of Pop went the weazel) Dont worry, it happens to all of us.

update
 

Ok i have just polished piston it has come up VERY smooth but i have taken off some of the yellow coating of the side of the piston (is this bad) still seems to have good compression

Re: Re: Re: new engine?
 

Good to know that ! So now you need to clean that black stuff off and check if the surface is rough. Like what Baxter mentioned, we need to put this aside and move on. Most important thing is that you've learned from that experience.

Re: Re: Re: max engine
 

Instead of using metal polish like AMG, I prefer to use a toothbrush and dishsoap (the cream one).
If you can clean the black deposit on top of piston troughly (without using metal polish)... then the engine is still in health condition. Just wrong setring, use colder plug and or better fuel.
The (not-perfectly) burnt fuel/oil is creating that deposit.

If.. the carbon still there and the top surface of the piston is like being hammering by thousand needle.. creating a rough surface, then you have a problem.
That is early stage of pre-detonation, your combustion chamber is explodes far before TDC .Could be the plug is to hot / too lean setting . If you keep this setting, result is obvious.. broken con rod or broken crankshaft.

Just replace the con-rod and learn to setup again. Rich to lean, dont do lean to rich. !

Re: Re: Re: Re: Re: max engine
 

SMILE, I dont think you damaged it too badly, what you do is this, clean everything as clean as you can with some nitro cleaner, then take pics so we can see again. How are your bearings? You say the piston only gets halfway then jams, this is good as it means that you still have the pinch. How are the bearings? does the crank feel smooth and easy to turn when you turn it in the case? You might still be able to use the motor and it may still make good power, in fact, I am sure it will, as long as you dont have a damaged piston. Follow this guide to the tee and you will have a great running motor, ESPECIALLY after something like this, but I must say, only if the piston is not too bad.

This is very contraversial, But i suggest this after the motor has been overheated and rebuilt.


Remember that you mainly want to heat cycle the motor and let the components settle to the running conditions. What this means is run the motor in with the same fuel you intend to run the motor on. Run it very rich for about a minute, then stop the motor and let it cool completely, do this for 2 tanks, stopping the motor after a minute and letting it cool completely. Then run it a little leaner, the same way you did previously. You may want to run the motor in the car on a bench with a fan, letting the motor idle. After you have leaned the motor on the 3rd and 4th tanks, Lean it to slightly rich, then run the 5th and 6th tanks. now the car is nearly ready, take the car and run it at MAX 1/2 throttle, but cycle the speed up and down, but stop every minute and let it coll completely, do this for one tank. Once this is complete, with the motor rich, run it to full throttle and down to 1/4 throttle, cycle this for a minute, try to get at least ten cycles in the minute, stop and let it cool, do this for a tank. You can now set the car up to race tuning and run it as you need.

Re: update
 

Ah, that's one more positive note ! :nod: :D

Well, you should not touch the piston side but nevermind. As long as the piston or liner is not scratched, then it should be OK.

Guys... you were posting too fast:eek:
I start to reply.. then I must answer some phone calls, after click the submit button.. its too late I guess..:lol: :lol: :lol:

You need faster servos man ! :nod: :lol: