I want to run in my O.S. Max .46 FXi engine that came with my Hobbico NexSTAR 46 Select 4-Channel RTF 68.75", which is my first plane.
But I am not sure or the engine will have enough cooling when it's run in on the banch ...

And how exactly do I have to do this ? Just attach it to something and put a propeller on it ... ? And how many tanks do I have to run through it ? and do I have to run it rich or lean ?


hope you guys can help a newbie in Planes out,
Prophex

PS: !!! Just turned 18 TODAY !!!

prophex, happy birthday! There are commercially available engine stands used for breaking in an engine, or you can use an extra motor mount that you have laying around. Just attach it to something secure. MAKE SURE THE MOTOR WILL NOT MOVE OR BREAK FREE OF THE MOUNT--HOWVER YOU DECIDE TO MOUNT IT. Put a prop on it (as recommended), and start it up. You will have to have (of course) a fuel tank hooked to the engine. Try and make sure the tank is at the recommended level (or, if you can't find that info out, just place the tank a little below the carb). Hook up the fuel lines and go. The manual should tell you how to break it in, but you'll want to be a little rich at first. However, you don't want to be too rich, as this will cause problems because the engine will not get hot enough for the cylinder to expand properly, and you will cause a lot of stress on the connecting rod. (I'm assuming this is an abc engine). Also, have some provision for the exaust, because these engines can give off poisonous gases, and you don't want to be inside of a closed room running this engine. We usually do it in a workshop, and put a piece of metal pipe over the nipple of the muffler, that ends in a gallon jar. That way, the excess oil will be collected in the jar, and not on your floor or walls! Stay out from in front of, or on the side of the propeller. It can come off. Just be very careful. After a couple or three tanks of fuel, it should be about ready to fly. THere are way more qualified people on RCU to help you out, but that is my 2 cents worth. Just follow the directions on breaking it in. But, as far as operating it on a bench, yes you can. Make sure it's secure, though. And, I mean secure with bolts and nuts, not screws. Good luck

Prophex-

2slow2matter gives good advice for how to bench run an engine. The question is, why? You bought a Nexstar because it's RTF. If you take the engine out, you're sort of defeating the purpose. There is no reason to take the engine out of the plane to break it in.

Just follow the OS break in instructions with the engine on the plane. You should only have to run one tank of fuel through on the ground before it is ready to fly. Just have someone help you restrain the plane or use some type of restraining device, because break in should be at full throttle. I just did this a few weeks ago with my brother's plane and an OS .46 LA. I think we actually ran two tanks through, just to be safe. The remaining break in can be done in the air.

Have fun!
Scott

Prophex,

I agree leave it in the plane and break it in. I have done quite a few of the OS46AX engines and had done everyone of them exactly like the manual calls for and have never had even a small problem.

You really only need to breakin on one tank, doing two tanks won't hurt. If you do one tank on the ground, fly the next tank with the engine running a little rich but avoid prolonged nose high flight like vertical climbs and extended full throttle runs. After the second tank that you fly with, then start to lean it out for max rpm minus 200 to 300 rpm rich of peak rpm.

I'm just used to heli engines ... And you're better breaking those in on the bench. Guess it doesn't really matter with a plane engine.

thx for aal the input

Make sure to use an anchor such as a soft rope tied to a post and the other end to the horizontal stabs to keep the plane from jumping forward before you run the engine. For break in follow the instructions. The engine is a non ring type which means that you don't break it in while running too rich or you will have lots of problems. I found that the OS engines run very stable after the 3d tank so I so like to burn 3 full tanks through a new engine before I let it pull the plane into the air.