Eagle Flyer

My Feedback: (84)

I just did a test run of a Poulan 42 conversion by Roy Scholl. Fired right up after priming. Timing at 28 BTDC and a Bambula 20x8 is giving 6700 rpm on an engine with a ways to go to be broke in. Stock carb, and I am wondering if it is too small from the way it is responding. Any body ran one with something other than stock?

smallplanes

My Feedback: (3)

I'm not sure on carb. I've just converted a poulan 46cc and i got around 7600 with stock muffler. I made a pitts muffler but have not tried it yet. What ignition is that your running on the motor?


Thanks
smallplanes

Eagle Flyer

My Feedback: (84)

I ran a 46 on mag with some props but can't remember what the #s were now. I didn't have a muffler on the 42 durring this first run. Maybe that will improve the numbers some. I worked on a rotater manifold tonight. Almost have it finished. If you notice with the stock manifold the adjustments point at the prop and the throttle and choke isn't a straight shot either. Solving 2 problems at once.
The ignition is built by Roy also.
He did the ignition, hall setup with led indicator to show power, mounts, prop adapter and all. Nice work. Check out the size of the ignition box. That's a quarter setting on it! Magnet is a nice setup. Clamp ring on the hub. Just rotate it to where you need it and tighten it up.

Eagle Flyer

My Feedback: (84)

What prop were you using to get those #s ?

smallplanes

My Feedback: (3)

I was using a 20-8 pro zinger. I made my own prop hub,carb mount and instailed my magnet too. This is the first convert fo me. I'm also working on a 21cc i tested it the other day and got 10780rpms with a 3 blade 14-9 MAS prop. I also tested it with a 16-8 APC prop and stock muffler and got 9500 rpms. I made muffler for it that got the 10780 rpms.

Thanks

Eagle Flyer

My Feedback: (84)

Seems I was getting some where around 7000 with a couple of different 20x10 props on the 46. Can't say for sure though. I have another 46 like new waiting to be done. Think I will run it some more in the saw first. Also have another 42 converted in a plane. Will run it tomorrow maybe. If you notice on the test stand the carb is angled down. Another reason for the rotater manifold, to level it out. Doesn't prime at all hardly. Gas, like a lot of things, runs down hill, and out on the ground. This is something I noticed on my ZDZ 40. By holding the tail up, tail dragger, while priming it starts A LOT easier. The gas actually goes into the engine then. I wonder how many people don't realize this? Here are some pics of the 42 in the SPAD.

w8ye

My Feedback: (16)

A 18-10 should be more like the prop to use on a 42? About 7400?

Enjoy,

Jim

mikenlapaz

when rotated to topside needles the diaphram vent will be direct in prop wash. Check your rpms with a shield between prop and carb. Had one that did not want to turn up after rotating carb. Be interested to see if it affects your rpms

Eagle Flyer

My Feedback: (84)

If you look close at the previous pics the diaphram vent is on top at the back. Air could blow over it, but not directly into it. Look at these pics, they are a little fuzzy. Got too close with the camera. With the rotater manifold I built the needles and idle adjustment are pointing up and the diaphram vent is on the back and bottom, though you can't see it.
It picked up a 100 rpm with the straight in manifold as opposed to the original angled one. 6800. Bambula 20x8. Put on a muffler and might have lost 25 to 50 rpm. Then tried a APC 20x10. Pulled 6400 rpm. The carb just started to need a little leaning out on the low side when I quit. Engine has a ways to go to settle in yet. Hope it picks up some then.

Antique

My Feedback: (4)

A Poulan 46 will run about 7000 with a MA black plastic prop, around 6200 with a Menz 22-8 wood prop.....[8D]

Eagle Flyer

My Feedback: (84)

Running the 42 some more to get more time on it. Today it didn't want to start. Then finally it did then died after about 3 seconds. Kept doing this. Only way to get it to start again was to turn the ignition off and on. Checked battery voltage couple times, showed good. Then one time it went to nothing almost. Kept messing with it and something in the battery pack/wiring is giving out. A 2700 mah nimhd. Put on a standard 600 nicad and away it went. I had charged it with a 50 mah over night charger. Read some where, though I don't know if it's true or not, that kind of charger won't properly charge that kind/size of pack. So I put it on a lot faster charge and tried it again. And it ran, but only for a few minutes and died again. Still checked a good charge. Guess it's going into the "no good" pile. I took that battery out of the reciever pack setup for my Byron Cap 21 I am getting ready. Glad I caught it now. It's not very old or seen much use.
I am using the Hanger 9 combination tach and battery checker. what else are people using and how do you like them?

smallplanes

My Feedback: (3)

I've got a volt meter just like that one and they work good. I also have a Futaba 2000 meter also and i like it too. You can charge your battery with the 50mah but you will have to charge it for at least 2days to get a good charge. The 50mahs is almost like a trikle charge.


smallplanes

mikenlapaz

Eagle Flyer
The clouds lift and now it is clear. In third pic I mistook something brass colored to be linkage on back side. Oh well... no harm no foul.

marc morin

My Feedback: (1)

I have a Poulan 42 also just acquired a conversion kit I'm getting anxious on firing it up but waiting on C.H. ignition .Carb does seam a little small but 6800 rpm or so doesn't seam so bad on a 20-8 prop .Just what could I expect in Gains by going with a bigger carb and how much bigger to go ?

mikenlapaz

marc morin
Measure the venturi diameter, smallest part and post what size it is. Need a basis of comparison.

ScottB

My Feedback: (5)

My Poulan 42cc Conversions turn a Menz-S Prop at 7000+ Rpm and put out 21 Lbs of static thrust. This is with the stock carb.

Scott Baldridge

captinjohn

Scott: What was the dia and pitch of the Menz prop you used? Thanks Capt,n

ScottB

My Feedback: (5)

I guess I did forget to include that vital information. It was a Menz-S 20 x 7 prop

marc morin

My Feedback: (1)

The info from Walbro web site says that my carb no: is 11.1 mm venturie size .The quadra 40 with reed valve set up is 12.4 mm venturie size .Do reed valve engines need bigger carbs ?My quadra 40 only pulls a 20 by 8 zinger to 7200 rpm max reliably .

captinjohn

That is a good question. My opinion is they do not NEED a bigger carb, but can use one because of the way reed valve engines work. I have heard set up right.....reed valve engines have stump pulling torque. I seen a go cart engine that had 3 carbs transplanted to the crankcase. It sure did go. Capt,n

BenWillis

Does anyone SELL a carb rotator manifold for the 42cc poulan??? I am in desperate need of one!!

Thanks,

Ben in SC

ScottB

My Feedback: (5)

Ben,

I have have the rotator intakes you are in need of. The price is $15.00. Send me an email if you are interested and we can exchange shipping info. [email protected]

Scott Baldridge

BenWillis

Email on the way.

Ben

BenWillis

Scott,

Got the carb adapter today! Got here quick and looks great!!!! If anyone else needs a conversion part I highly reccomend Scott.

Ben

tim220225

My Feedback: (4)

My Poulan 42cc from a Craftsman saw turned a MA 18/8 at 7980 RPM steady. Have a WT289 carb and a G10 carb block I made for it. Didn't even taper the cylinder side. Could probably get away with a little bigger carb as the formula for carb size I made on Excel indicates a little over 12 MM size at 8000 RPM.