I think I have a 21cc featherlite here. I have a good carb for it. I have a CH ignition for it. Where can I get a prop hub and a backplate mount? I did a couple searches and came up with old posts from 2003 and 2004. Conversions have come a long way since then. Somebody has got to be running one of these.

I'm planning to mount it in a Midwest Citabria. I'm hoping the engine will turn a 14-6 around 7000-8000RPM. I haven't done and machine work to it. Is there a larger carb that works good? I have the WT615 with choke plate and twin needles. It's got an 18/64 venturi.


Any comments on these engines?

Try these:
indianatinygasengines
rcign
chign
topcat01-ebay
what size do ya need,i might have one.
flyrc100-rcu classifieds maybe
wackerengines

I've been working with one of these and you should be able to hit the rpm your looking at. I've got a 14-8 on mine (its what I had on hand) and get around 7300 with stock ignition. Muffler has baffle removed with a 2'' x .5 diameter discharge extension welded on. I'm still fighting either an air leak or my carb is too big. To get high mixture close my needle is about to fall out running with about 1/4 choke. Adapter was made from stock square drive drilled and tapped with a large diameter washer welded on for prop.

I don't think mine is going work out for my project though. Was going to put it on a bridi old timer but I don't think its going to have the umph needed.

Dave

I ordered a "timing kit" from Terry @ CH today. He's a really fun guy to talk too. [sm=thumbs_up.gif]

I am pretty certain he is sending a hub with magnet and a bolt/washer for my prop. I forgot the backplate mount and had to call him back immediately. He had both in stock. I totally scored today. Very excited to get the parts and fire this bugger up. I want to make sure it runs okay before I drill my firewall.

Thanks for the suggestions buck 1856.

My 21cc had the long shaft so a prop hub consisted of only a spacer, as for performance i was getting 6800 on a 16x8 TF wood and 7200 on an APC 17x6, i was running on the GAS/GLOW setup and the total weight of the engine was just under 32oz.

Good info. Thanks guys.

I have been reading threads in this forum on the 21cc engines. Also the 18cc engines. I am going to go measure the timing on this engine right now. I'll post the numbers in a day or 2.

It has a Walbro carb. The carb is 18/64. How big do you think I can go if I port it a little and drop the cylinder down to .020"?

I did one of these 10 years ago. I found it in a trash can along the road. Used stock ignition with the flywheel shaved and balanced. Had a Carpenter hub and back plate. Used a carb from a Homelite 25 which is 5/16" venturi. The engine did 7200 with a 14/8. I eventually gave it to a friend who has never done anything with it.

Thanks for the info on the carb size Jim. [sm=thumbs_up.gif]

Now if I can get my brain wrapped around converting that to 64thsd inch, I should be good to go. [sm=spinnyeyes.gif]

Seams to me thats about 20/64ths.


................... off to rummage through my box of parts and find one close to that size.

Carr Precision has parts for conversions on the Featherlites http://www.carrprecision.com/Pages/prod02.htm I have two featherlites,one has 22 cc on the label on the engine and the other has 18cc.Might convert one of them someday.Right now the 22cc is wackin weeds and the 18cc I haven't gotten to run yet.

w8ye, thanks for posting your carb size, thats what I've been trying to use so I guess it's not too big. New gaskets all around helped some but still can't seem to get enough adjustment on high needle. I'm about to go back to my Homey I originally slated for this plane. I'm out of ideas.

Sorry to butt in Rcpilot.....I've got a pile of these things rescued from the local recycler and would love to hear one overhead...

This thread is interesting for porting a poulan...


http://www.rcmf.co.uk/4um/index.php/topic,19374.0.html

I tried working with Carr Precision, since they advertise the Featherlite conversion. It's extremely difficult to get anyone on the phone. I tried no less than 2 different email addy's on the site and both bounced back as undeliverable. Finally got somebody on the phone a week later (after about 20 attempts at calling during regular hours) and he says he doesn't have any parts in stock. It's an older engine and not much power. Not worth converting.

Screw it!! [>:]

Called CH and Terry answered the phone on my 1st attempt. Had the parts in stock. Sent them out that same week. I had the parts on Friday. $60. Thanks Terry!!!

I'm planning to run the engine in stock form first. It if turns a 14-6 or a 15-6 at any decent RPM, I'll just fly it. If it hasn't got enough power, I will run a couple different props to get some solid baseline numbers and then I'll tear it apart and port it. I've been reading threads on porting this engine.

I don't have a larger carb. I do have 24/64 and 30/64 carbs, but those are WAAAY too big. Stock carb is 18/64 and W8YE said I could probably use a 20/64. I might be able to dig one up somewhere, but for now it retains the stock carb venturi. I did swap out the factory carb with one that has a choke lever. Same size venturi, just a choke lever to make starting easier.

I found some thinner gasket material for the backplate. It's 1/2 as thick as the stock gasket and still leaves 1/16" between the crank pin and the backplate. That alone would probably stuff the case enough to show an improvement. I haven't bought it yet. I wanted to give the engine an honest chance at putting out good numbers before I started modifying it.

Thanks for the link Cogburn.

I just hope it runs. I'm not drilling my firewall until I know this is a solid runner.

the crankcases are the same between the 18cc and 24cc engines (at least on the 4 bolt backplate versions), so most of them probably interchange, makes it very easy to plop a new piston/jug on and test other sizes

the threads on the crank are 5/16-24 like homie's

I have one 21, a scored to heck 18, a good 18 (I keep it around as a weedeater, works good), a good 25, a scored 25, a 24 that needs a ring, and a good 24, they all seem to have most of the same parts, I've ran one 24 with the plates removed from the muffler, it isn't all that loud and works fine, it cuts the weight of the muffler nearly in half

My muffler has been gutted. It's nothing but a can now.

My dad has a 25cc Featherlite. I might take a trip to his house (3hrs away) and sneak into his garage to do a head swap with him. [sm=lol.gif] I just gotta figure out a way for my wife/kids to keep him busy while I strip his weed eater and swap heads and pitons with him.

Then I'd have a 25cc. Dad won't know the difference. He idles his anyway. Not many weeds to cut in southern Colorado. It's dry as a popcorn fart down there, so nothing grows much.

Had best #,s w/blower engines 4 bolt b/plate and bolt on muffler,long shaft can be chased and cut to short shaft,bigger transfer ports in them,8450 rpm w/apc 17/6 or 16/8,havnt tried synthetic oil yet,good luck!

P.S. 2.10lbs auw w/prop,if you take the time they actually polish nicely too!

dangit, why'd you have to say that... my scored to heck 25 is exactly that, a long shaft 4 bolt with bolt on muffler... nothing but parts now...

I forgot to mention that, I had my 18cc right at 2lb or a hair less with prop set up for gas/glow, but then realized the compression is too low (is scored some)

My compression feels low. Might need a ring. The piston and cylinder look good. There's some blow by on the piston and a little carbon on top. I was able to rub a lot of the carbon off the top with a paper towel. Ring is free-floating. It could be just the engine is dry or the ring may be shot. I'll have to start it to know for sure.

LAST parts, so dont everybody get all excited. If there is a demand we might make another run. Took a long time to use up the last run

Wacker engines has parts for the poulan.

http://www.wackerengines.com/Other.htm

I have a 25cc that will run 8000+ on a mas14x8k on gas glow,,,idle is a little high though.

I bought a 25$ ignition from hobbycity and will mount it sometime to see what it does for reliability. If it works good I might try it on a Dragon Lady but it is still a little heavy for that size plane. If I get really ambitious I might see about an oversize Quaker or something similar. Should be enough power to fly a BIG Quaker(12ft+?).

When all else fails let logic do some troubleshooting. My carb was bought "new" from bayworld and certainly appears new. I didn't want to tear it apart but, voila', crap in jet = only run with choke on.

Now it is SWEET!. 7800 with MA 14-8, idle a little high but not bad..

Guess it was debris from factory assembly but what a pain.

Dave

Thats awesome man!! Glad to hear you're getting it running good. [8D]

7800 with a MA 14-8? Is that stock? Or did you port it? Thinner base gasket?

I noticed the backplate gasket on mine is REALLY thick. It looks like I could use a thinner gasket and stuff the case. I think my stock gasket is 1/16" thick at least. The backplate is 1/8" away from the crank pin. I could use some liquid gasket maker and probably get a nice boost just from stuffing.

That is stock ignition, a "20"size carb, and no porting even considered. I did replace the back plate gasket but it is at least as thick as original.

_______________

Dear Sir

I have got a Poulan Feather lite converted

Do you wish i send you detailed pictures?

Best Regards

Nuno Monteiro From Portugal

I have got a Poulan Feather lite converted

It is a very very smooth engine in my test it run a regular grey propeller 15/8 Graupner 6000 rpm
It as a very very small hole carb ( venturi)

It is a light engine , but powerless i belive , it need some modifications to run with some increased RPM´s

I believe Ryobi/Mtd 31cc it is more powerfull , and swing a 18/6 18/8 with facility smoth
Run by magnet not modified for CDI

If modified for CDI it will run different

Do you wish i send you detailed pictures?

Best Regards

Nuno Monteiro From Portugal