195LikesNovarossi engines thread
08-20-2012, 12:03 PM
#4396
Tech Initiate
That thing ate something. That is not detonation. Looks more like a piece of bearing/other foreign metal or glow plug element.
08-20-2012, 12:05 PM
#4397
Tech Initiate
How is the conrod's big end? Have you checked the small end to make sure no pieces are missing? There seem to be marks on the conrod as well, close to the piston's skirt.
08-20-2012, 12:38 PM
#4398
Novarossi .12
I want to know what nova .12 is the best for the money? Please help
08-20-2012, 04:50 PM
#4401
Tech Rookie
Maybe some piece parts can makes this accident.
I will check all parts of engine and I will exchange the conrod to new one.
Thanks.
08-20-2012, 04:55 PM
#4402
Tech Rookie
No damaged at the side of the piston, I would say if you did not have a blown plug or a broken ball from a bearing it must be a to low head clearance. First of all check the play on the main bearing and conrod. If that is all OK then you must add at least 0.5mm of headshims.....
I will exchange the conrod to new one.
And then I will test this engine with more shims.
Thanks.
08-20-2012, 05:21 PM
#4403
Tech Rookie
Ever seen the result of a pre-detonation? That looks more like it was sandblasted, this is not. And the moment has nothing to do with the opening of the exhaust.
Normally you get the ignition just before TDC and because there is a slow reaction the combustion after TDC. With pre detonation the combustion will start just before or on TDC making a uge pressure.
This looks like dirts from somewhere or I would say a to low head clearance.
Normally you get the ignition just before TDC and because there is a slow reaction the combustion after TDC. With pre detonation the combustion will start just before or on TDC making a uge pressure.
This looks like dirts from somewhere or I would say a to low head clearance.
So, as you said, I think, it means some dirts from somewhere make scratch not only the conrod but also piston & under-head.
I will check every parts of my engine and make them clean again.
Thanks.
08-21-2012, 04:33 AM
#4404
Tech Master
08-21-2012, 08:22 AM
#4406
08-25-2012, 05:50 AM
#4408
hi.there is a back plate with steal insert for 11.5mm crankcase 12 novarossi engine?i have seen engines with that type of backplate but they are for 11.9mm crankcase.
08-25-2012, 11:30 AM
#4409
Tech Elite
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08-25-2012, 12:20 PM
#4410
Make less scratches on the aluminium part 