I am having tuning challenges with my .21 Nova Keep-On; in fact I've killed the original piston liner after 1 race and just ran in the replacement.

Engine behaves very strangly : it pulls well from low to mid but doesn't rev out after that. It's as though the engine is experiencing fuel starvation. Tried richening it but still the same, until it was obviously too rich. Engine runs very hot 130 degrees C.

There is very fine pitting on the piston surface and top plate. I think it's pre-detonation. But I am using stock shimming ( 2 silver and 1 copper - measured head clearance 0.6mm) and stock No.8 Nova plug. 25% nitro and 9% oil.

It's not the fuel tank nor the fuel line as my other engines were working fine.

Needle setting : HSN flush, LSN 0.3mm in, MSN flush

Any suggestions ?

Cheers

If you run on a track with a very long straight, add another Copper shim under the head...

LSN is normally flush to slightly out (1/4 turn) so I think you are too lean on the bottom.

Like it was suggested, also try adding a .1mm shim. With some fuels, it is necessary add the shim. Also, you didn't specify which #8 plug you are using but we recommend the C8TGH plug.

What you said makes sense. I think I was not running the motor with enough head clearance. I needed to lean the bottom to stabilise the idle or it would just cut. And it wasn't too rich or lean, and the idle was set higher than usual. Likely too high compression when fuel mixture is in the combustion chamber.

I use the C8TGH plug. VP Powermaster 25% fuel. Will try shimming up.

Cheers.

I bought a keep on .21, and I think this broken (5 liters). The Engine pushes a lot in low and medium rpm, but high rpm still not fine. To run fine at high rpm, the temperature rises to 130 ° C. Is this normal? Still need more breakin?

From Novarossi site:

-The right engine temperature will vary widely, depending on the air temperature, fuel used, altitude, driving style, air flow conditions of the body and several other factors.
There is absolutely no way anyone can tell you an ideal engine temperature.
It is generally accepted that a proper range of temperatures is between 95 and 140 degrees Celsius (or about 203 and 284 degrees Fahrenheit).
The biggest variable of all in measuring engine temperature is where and how the measurement is taken.
Your infrared thermometer may be calibrated completely different than ours, or you may be pointing at a different spot on the head.
We usually check the temperature pointing the infrared on the glow plug.



High temperature with the new low profile coolingheads?

The results of test show that forced convection heat transfer rates can be enhanced by up to X using low profiles cooling design. With the low profile heat sink, the measured temperatures on its surface can reach 15 to 20 °C / 59 to 68° F higher than normal because the temperature detection is done close to the glow plugs.


GHN

HI guys im filling out a consumer complaint form and need to find the serial no. for my Novarossi flash .12 3port engine where can I find this please?

Oh? What is the complain?

The S/N is normally printed on de sidepart of the mounting holes or else on a paper listed in the box.

Thank you. Well im new to rc and when I explained this to the hobby shop they sold me what I thought was a new motor but when my friend had a look as he was going to fit it all up to the car he told me it was used and take it back. Long story short they pretty much refused to replace it with a new one nor refund me so I put in a complaint to consumer affairs I attached pictures with descriptions

Did you buy a pre run in motor?

pre run stock do not have spring mark at the crankcase

+1 what is the part number on the box. This will say if this is a pre-run engine.

Interesting.... Damaged headsrews... I do believe pre-runned engines are checked but I would expect they have the right tools for such screws with a minimize of damaging.

THink clearly here, common sence. Why would Novarossi, with a reputation to uphold, ship a used engine. If somebody sold you a used engine it was the HOBBY SHOP where you bought it. They should be ones that will be getting the consumer report, NOT Novarossi.

Like you said, the HOBBY SHOP sold you the motor, not Nova. Plus you explained to them that you were new to the hobby and probably tried to pull a fast one on you. How do you know that it wasnt the HOBBY SHOP that used it before they sold it too you?

I agree, Novarossi has done nothing wrong. Is this a pre-run engine?