I just bought my trainer, the nexstar. But I've got a few questions
1. I followed the o.s. engine break in instrustions and ran a tank of fuel through it with it sitting in my driveway. My concern is that I am deffinetly getting bubbles coming trough my fuel line. Not enough to stall the engine but it was deffenitly sputtering. I am hoping that because the plan was sitting on the ground this some how created more vibration then it would in flight, thus not being a problem in flight. Or do you think I have a whole in my fuel line.

2. I have a nitro powered truck and I know that one of the most critical things to do is run after run oil through the engine at the end of the day. Do you do this with aircraft engines as well. I would have thought so, but I didn't read anything about it in my instructions. I went ahead and put a little in the engine and turned it over a few times to be safe, I hope this was the right thing to do.

I appreciate any answers.

If you have bubbles on the ground you're gonna have bubbles in the air. I don't think Hobbico puts any foam around teh fuel tank in the Nextstar, you might want to pull the tank and put some foam at least on the front of the tank where it touches the firewall. Ideally the whole tank should be surrounded by foam but I know that's impossible with the Hobbico planes as the tank fits very tightly thru the former. As long as you have tank out, you might as well pull the stopper and check the fuel line inside the tank, actually just replace it as you might not notice a pinhole.

I would say if you're gonna put your engine up for a month at a time, then definetly afterun oil. But if you're flying every weekend, and make sure to run all the fuel out of your engine before you pack it in, then afterrun oil is an option.

Andy

Thanks Andy

You know I love to tinker on things, fix things, but a brand new plane. Especially my first one, it kinda gets under my skin. I mean it doesn't sound like to big of a deal but still. I'm going to do what you advised and wrap the tank in foam. I'll probably switch out all the fuel line just to be safe and hope for the best.
Thanks alot

There isn't any room to pad the tank.
Just run it rich and fly.
Just make sure that the plane transistions well and that it doesn't load up or run lean.

Is this a common problem with all rc aircraft or just one that the nexstar is paticularly prone to. I hate to just live with it. Is there anything else I can do

Are you seeing the bubbles in the line coming from the tank to the remote needle valve or in the clear line from the needle valve to the carb. Newer OS engines all have a remote needle valve and sometimes this line gets torn in the install process as the engine mounting bolts are right under the line and if the line is not removed during engine installation/removal, it is very easy to tear this line and not see it. Don't ask how I know that one.

Yeah, The bubbles I'm seeing are coming from the fuel line from the tank to the needle valve. I didn't notice any from the needle valve to the carb but that doesn't mean there were not any.

I agree then, it's time to take a look at the lines coming from and the lines in the tank.

I get a little bubbles, I have not used foam on the tank
yet... But I've never had any problems... I use after run
oil after mt'ing the tank after the day is over.. Cheap
protection... And even cheaper protection, that I've been
told works just as good or better... Mystery oil...
I've also been told to stop wasting my money with after
run as long as you fly atleast once a week and run your
Tk mt after the day...

Did you get the nexstar from tower hobbies? if so just call them tell them you have a problem with the tank and they will send you a new one out (thats what i did). i never had to send the original fuel tank back and when i had a good look at it they had the color coding of the lines mixed up do now i have 2 tanks for my plane

Nope, tried to be nice and bought it at the local hobby store. I doubt they will exchange it out. I'm calling hobbico tom. We'll see what they say. If I had to guess theres a whole in the line in the tank.
Thanks for everyones help

The tank in the Nexstar IS padded with foam, so the lines are a good place to start looking.

There isn't any foam padding around my tank. Wish there was.

Check the lines. Also, check for a loose stopper. I've had bubbles as a result of both these items.

Scott

had bubbles in my line i thought it was my pump but seems everything is working now it didn't have dead stick at all last weekend may have been the two tanks i ran through it on the ground the week before just to learn how to get it ready for training

There should be black form-fitting foam on the top & bottom edges of the tank-opening in the bulkheads supporting the tank -- if it isn't there, call the Hobbico support # & see what they say.