RCFAQ.com |
The complete radio control model airplane FAQ. |
Converting a 46cc Poulan Model 2750 chainsaw for model airplane use. This 2.8ci engine is almost identical in power and weight to a BME 2.7 (44cc).
2. Converted Poulan Engines
Back to Engine Conversion Home Page
Stock
This shot shows the intake side of the
engine (one with stock ignition and minimal modifications). As you can see, the intake port is oval shaped and the
brass tube for the crankcase pressure to the carb is very
close to it. I made a pattern of the intake port including the
brass tube and transfered it to a piece of aluminum the same
thickness as the length of the intake port. The diameter of
the aluminum is 1.650 giving me plenty of room for the two 5mm
setscrews that hold the adapter to the port. Be careful here,
the intake port is very thin cast aluminum and you need to
make sure that you don't bear down too hard on the setscrews.
The rest of it was pretty easy, I wanted the throttle arm
closer the the crank centerline, so I just positioned the carb
where I wanted it and used the metal carb spacer(gasket) to
mark the location of the holes to mount the carb. (Whew) Next,
I made a plywood spacer with the holes for the crank pressure
and carb bolts. You have to make a 180*groove in this for the
pressure to get to the carb. Don't forget to give this a coat
of 30 minute epoxy. Lot of work, but it can be
done.:
Below is a photo Of Ralph's motor. On my scale it comes in at 3lbs 7 ozs I have a Dave Patrick Extra 330l on order that this is going in. As you can see, he's turned the cooling fins down on a lathe, and added an electronic ignition.
Lightened:
All of the information on
this web site is copyright 2000 by rcfaq.com. All rights reserved.
Revised: February 09, 2002 .
email webmaster@rcfaq.com