TomiRC

Hi everyone! I need some help with Brake in my engine.

I have a Vega .12 3 port. I believe it is Italian made. In the manual says that I should use 10 to 15% percent fuel, and I am using 10%. Also it says that for brake in, I should open the main neddle 1.5 turns, and it doesnt say anything about the low speed needle. The carburator come with the low speed needle closed. The thing is that I tried to start the engine as the manual says, but engine doesn't start. I tried to open more both needles, and the engine starts, but stalls when I accelerate. When I open the main needle 5 or 6 turns, the engine seems to respond, but it stalls after one minute or less when I accelerate. It seems that there is a lot of smoke from the exhaust, but I dont see oil coming out. I dont know what to do! Please, help!

Thank you very much

SpeedBump57

I would start with the LSN at about 3-4 turns out and then get it to where it will idle some what on the bench but still rich. As for the HSN it sounds like you are way rich. If you are seeing alot of smoke but no oil it might be that the RPM's are not getting high enough to build up enough pressure to push the oil through the pipe. Once you get it to idle ok set the car on the ground and run it easy. If the car won't move and flames out lean the HSN until it starts to move but is still rich then finish break-in.

TomiRC

Thank you very much for your replay. I am going to do what you said right away, and I will let you know what happens.

Thanks again!

SpeedBump57

You are welcome! I hope things work out...

TomiRC

Hi Again, I did the changes you recommend me. First, I started the engine with the factory settings about the HSN, which are 1.5 turn, and I turned the LSN 3 to 4 turns. The engine started well and fast, and I let it to idle for a while. However, I realized the temperature was rising very fast. It went to around 250, and I shut down the engine. After that, I didn't touch the LSN, but I turn the HSN to 3 turns, and I started the engine. I accelerate a bit the engine, and it seemed to respond well, however, again it went to 250 really fast, in around a minute too. After, I turn first the HSN to 4 turns, and after again to 5-6 turns, but again the engine's temperature rised very fast. It seems that the engine doesnt respond to the HSN. Even when I open it around 5 to 6 turns, I didnt see oil coming out of the exhaust, only smoke, white smoke. Could someone tell me if my engine is defective? If so, which engine would you recommend me? I would like to have a decent one. Thinking in a Top .12 or Rex .12, or Picco engine. I have a Mugen MTX 4.

Thanks again for all your help.

Tomi

Artificial-I

iTrader: (17)

HSN really wont effect an overly lean lsn @ idle , just try adjusting your lsn. The hsn should do something to the low-end but if it doesnt its nothing to worry about. Just see if you cant get it to idle cooler.

TomiRC

Thank you for your answer, but actually, I have the LSN as rich as I can, at 3 to 4 turns. I cannot opent it more. When I have tried to adjust it, I closed it to two turns, but less than two turns, the engine stalls, so I left it 2 to 3 turns. Therefore, I have a rich LSN, and a rich HSN, but the engine still gets very warm. An even if I accelerate the engine, I dont see any oil coming out from the exaust. Does someone has any suggestions?

SpeedBump57

Tom,

First of all 250* is not that hot for a .12 especialy durning breakin. If you have lots of smoke there is not too much to worry about. Some engines are just real tight and will get hot until broke in.

"HSN really wont effect an overly lean lsn @ idle , just try adjusting your lsn."

AI is right here!

During breakin the low speed responce should not be crisp at all, if so you are to lean on the bottom. If at 3 to 4 turns on the LSN it is too rich and loads up and or dies turn the idle screw in a bit until it stays running. If you are not driving the car and getting the RPM's up the HSN won't do anything for cooling.

What kind of temp gun are you using. Unless you are using one of the better ones (exergen, SP?) I have seen temps off as much as 40 to 50*. When I am breaking in a engine I will heat it up to about 250* with a heat gun before I even turn it over. After it is running I try to maintain temps between 230* & 240*. I do this by wraping the head with tin foil. This alows me to run very rich and still keeps the temps up.

Richen up the LSN!

If you have any more questions just Post up!

Scott

Artificial-I

iTrader: (17)

Hmmm. So when you went to 3 to 4 turns on LSN and it was hot you then decided to close it? This will make it leaner , making your problem worse. Less than two turns and it stalls. Sounds like your leaned it out so much it shut down. That will happen.

Just try taking it back to 3 to 4 turns...and maybe more if possible. Im guessing it will load up and stall that way too?

Also if you leave it at the 2 to 3 where it was close to stalling out from being to lean. It shouldnt be rich when left at that point. Go back to the 3 and 4 out on the lsn.

Also what plug are you running , is it a hot or cold plug. As well is it new nitro fuel and what company and percentage is that?

TomiRC

Thank you for the replay. Actually I left the LSN at 3 to 4 turns open, just at the point where I start to see a red 0-ring from the needle. The engine seems to work better, but when I accelerate the engine doesnt respond well. I tried to lean out the HSN, but I dont want it to lean it out more because the engine gets hot too early, just in a minute or less of low acceleration.

I tried two plugs, one hot and the other medium hot I believe, and both seem to work ok, I think, although the plugs seem to get a bit darker. The HSN at this point is set aroung 2 to 3 turns open, which is more than the manual was saying of 1.5.

The fuel I use is 10% Omega fuel, as the manual was saying of not using a mixture with nitromethan not higher of 15%. However, now I dont know if the fuel I use is 10% of nitromethan or 10% of castor oil. Can someone tell me? In the bottle doesnt say anything. I sent an email to the factory and they told me I should try a fuel with a higher oil castor, around 15%.

Some suggestions?

SpeedBump57

Bryons 20% nitro should work well and you should be able to get it most every where.

Artificial-I

iTrader: (17)

Are you sure your using car fuel? Omega makes plane fuel?

That would be the obvious problem. Also yeah just switch to what you would use normally. 20% is what I use and most everyone reccomends. Byrons or Wildcat is the way to go.

TomiRC

Thank you to everyone for the great help.

Actually, the instruction's manual was recommending to use a fuel with 10% to 15% percent nitromethange, so I went to the shop and I bought just that, 10% Omega Fuel. However, as one of you was saying, Omega fuel is an airplane fuel with 18 percent oil, which I think is too much for a car engine. I just bought 16% nitromethane fuel with 12% oil, and I hope that will work.

Respecting which temperature gun I use, I am not sure if I already mention it, but I use a Venom smart temp.

I hope the engine is still ok!

Thank you for all your help. I will keep informing how the engine works with the new fuel.

Tomi

SpeedBump57

18% is way too much! Looks like your on the right track now. Let us know how it works out.

Artificial-I

iTrader: (17)

Yeah airplane fuel should never be run in a car motor, thats why it was running hot. Also what fuel did you buy now? Trinity Monster Horsepower?

Also next time you should converse with your shop a little on what your trying to accomplish. They should generally be able to offer advice so this doesnt happen to you.