I bought a used Craftsman chainsaw with a Poulan 42 cc engine. Now I'm going to convert it. Did anybody post a conversion of this engine?
I need a few tips,

Do I just cut off the rear shaft (not used) with a cut off wheel? I assume cut itas close to the bearing housing as possible.

Next, Do I leave the carb adapter , which is angled, or put a new one on it.

Also, there is a Zama carb on it. I have had a Zama on another gas/glow conversion (Poulan 25 cc) and it worked pretty goodonce I finally set it correctly (seems it wanted the low idle to be set rich and then it would run well in the air).

Just an observaton, this hasa nice mounting set up, just use a typical rail mount onthe crank case studs.

Sorry, I don't have anything to post Re: your Polan 42 but I do have some questions on your Poulan 25.</p>

Is your Poulan 25 the Feather Lite with the four bolt rear cover?</p>

How was the performance?</p>

The reason I'm asking is I have one that I'm concidering converting and I'd like to have an idea what to expect, performanc wise.</p>

Thanks</p>

I looked for my picture of the Poulan 42cc that I had converted but I can't find it now.</p>

Anyway, yes, just cut off the rear shaft, but be careful not to over heat the shaft and ruin the seal.  I often grind through the surface hardness and then hacksaw off my shafts.</p>

The angled carb adapter is fine.</p>

I run a bit smaller props than most as I don't fly 3D and like to have an airplane fly around at half throttle with a reserve of speed left.  So I used an 18 x 8 and mine turned it at 83-8400 rpms.  A more "normal" prop would probably be around a 20 x 8.</p>

Watch those Zama carbs with Gas/Glow.  I had two of them swell their diaphragms up and stop working after being exposed to the Gas/Glow fuel mix.  Never had that problem with the Walbro carbs.  If you have been using them with good luck, that's fine, but if the engine starts acting up, look at the carb diaphragms first.</p>

The engine is a bit heavy, but runs well and it's an easy conversion.</p>

AV8TOR</p>

Well, here I found the post where I had posted a pic of my Poulan 42cc.</p>

http://www.rcuniverse.com/forum/m_40...tm.htm#4628748</p>

Good luck,</p>

AV8TOR</p>

</p>

Hi Twinstar,</p>

   Yes ,it is the featherlite with the 4 bolt rear cover. I am running a MA 16 X 8 Classic. It runs at 7200 RPM. I'm using the stock carb. It is a bit tricky to set up. I run the low needle slightly rich. It tends to lean out in flight without it set rich.   I use fuel mixed 2 qt of premium gas with 1 qt methanol and 40:1 oil   </p>

 </p>

</p>

Wow , thats not bad. I didn't think it would be that good for a stock engine. Do you have any numbers without using methanol. </p>

I have a slightly larger Walbro carb with twin needles that I planed on puting on  mine. I am thinking more serious about it now with numers like that.</p>

Thanks for the pics AV8TOR. I'll let you know how it turns out.

Are you talking about a straight gas /oil mix? I do not have any numbers for that. The only time that I used a straight gas/oil mix was for the initial break in period which was all of 1/2 hour. I ran it rich and with the glow driver attached. It probably was running about 6700 RPM if I remember. Also, the Zama carb that is stock in the unit does have low and high needles. I had to cut slots on the needle heads so that I could use a screw driver for adjustments.A screwdriveris probably the best way to adjust the needles because you will need to make several minute adjustments.

I have a Poulan 25cc that I converted.  It is running on XYZ electronic ignition and with a WT 324 carb.  With an APC 16x8 I am getting 7100 rpms.  Only mods are the larger carb, gutted out muffler with two 1/2 inch holes drilled in it, and the electronic ignition.  Once I got the timing sorted out, it runs great.  I use it to fly my Dynaflite SE5a.  Flies it great.  Had a ball flying it yesterday.  </p>

</p>

Jim</p>