balsa brain

I have a new MDS 148 that I bought from a popular auction site that came nib with no instructions. It has the new carb with MDS on the front. It also came with what looks like maybe a pump that has a fuel inlet and exit. I put that on the backplate and ran a fuel line from the tank to whatever this thing is and from there to the carb. The tank is new with clamps on all lines. The muffler is a Bisson for a sideways mount. I actually have it mounted upside down so it would clear my test stand. MAS 16/6 prop. I started this breakin attempt kinda spur of the moment and did not have the battery in my flight box charged enough to turn this engine over so I did it by hand with a chicken stick and some with my fingures. This is the biggest engine I have ever tried to start and after I got past the flip and dive for cover or run period I started to get some moments where it would act like it wanted to go but never did. I worked the high speed needle from about two turns out to maybe four and never could get it to stop blowing fuel out the carb and all over me. It was getting good fuel draw from the get go. Morgan's 5%. I don't think the muffler being upside down is an issue but I've been wrong before[] Do any of you fine folks know where I can download operating instruction for this engine? I have searched the forums and fould nothing about getting the 148 started but rather plenty about keeping them going. Any advice would be greatly appreciated. I am going to put this engine on an Ultra Stik LIte 120. Thanks in advance for any tips.

Bill

Hobbsy

My Feedback: (102)

If it is indeed a new engine it won't start very well until you get about an hour on it, by then it will have some serious compression and start with one backflip every time. A 16x6 is a little light for it. Once you get it tuned it will run very smooth. The muffler position should not be an issue unless it gets a lot of fuel in it. Set the LS needle at about 1/16 inch or slightly more from the end of the spraybar at full throttle. The Bisson Webra 1.20 /MDS 1.48 Sport muffler is a good choice for upright running.

balsa brain

First, let me thank Torque Wrench for the reply. I tried to get it going with a backflip and got it to cough a time or two. I will check the lsn and adjust it to where you say. Between the sand knats eating me alive, the Morgans shower I was getting and the frustration in not geing able to get this bad boy to run gave me a good feeling as to what a can of whoop arse being opened must feel like[]

Bill

BelAirBob

This is probably way too late since you posted this over a year ago, but the MDS 1.48 has developed into one of my best engines. It starts with one hand flip of the prop every time. I am using an OS #8 plug I think....maybe an A3....it has been so long since I changed the plug. I use 15% S&W fuel and a 16X8 prop. Takes my UltraSport 1000 straight up. I have a Snuffler on it.

bob