I finally got it running. It is the same project as the post regarding spun bearings. I ended up getting a new case. It finished at 5-pounds without the ignition. With a WT-542 carb, the muffler shown and a 20x10 power point I am only getting 6700rpm. The ignition is peaked to max rpm as is the carb. That is about 500 less than I expected. I would guess it should match a G62 which claims 7200 with that prop. Any ideas? Bigger carb??

Before I made drastic changes I would get a more efficient prop. Personally I never like more than an 8 pitch on big singles. My opinion here. Look good otherwise.

Tim

For now it is only for comparison purposes. I'll fuss with props when it's in the plane.

I would think it would do better.... I threw an Echo 58cc together a while back and it turned a Top Flite 22 x 6-10 at 7000.

How is your ring gap?? Another thing that can trip one up is getting full throttle. We usually remove the stop from the throttle and set the idle with transmitter trim. That's fine, but you have to watch that the throttle butterfly doesn't open TOO far and go past center, actually closing the throttle somewhat. I once had one that was a bit down on power, and found out that there was just enough slop in my throttle linkage that the engine would suck the butterfly partially closed while running....

Just looked up your carb.... On that size engine it wouldn't hurt to go to a 15mm carb, but check everything else first.

AV8TOR

I tried a zama carb, the one the saw came with one of the 650 sawsand got about the same result. I did install a velocity stack and a much larger volume muffler. I did not measure the ring gap. The leak down is very slow, if that means anything. It does not want to idle down real slow. It could be the rings you're right


A 20x8 turns a little better than 7K. The front oil seal seems a bit tight, it squeaks. It is brand new though. I can't imagine that tiny bit of drag would make a difference. I put it in my Big Bee today. I'll fly it and see how it goes. The parts are a mismash from different engines so maybe it just needs to break in a bit?

I was expecting about 5-hp. I was thinking I could do as well as a G62. I appear to be getting about 3-HP That is from this calculator.

http://personal.osi.hu/fuzesisz/strc_eng/index.htm

I had visions of this engine being a real powerhouse. Apparently not, no big deal. I got a more than the CS-510 so that is good. Actually, calculating it out I have more than 30% extra horse power. Since I went to an engine that is 30% bigger, I guess I did OK.

Squeaks in the oil seal usually are caused by the seal being dry. I always put some assembly lube on the inside around where the spring is. Don't think it would mean much to performance at any rate.

What size is that exhaust outlet tube? I checked my DLE55 and it is around 7/8". That could have you "snorkeled" down a little if it was on the smaller side. The Xoar props are pretty good for the money. I get mine from Valleyview.

OK, so I got new rings and a wrist pin bearing. It now spins a top flight 20 x 10 at 7000. It spins a 20 x 8 apc at 8000. I'm thinkin' I will get a menz or bambua 22 x 8 and see what happens. I am predicting about 7300 with one of those. Oh, it idles reliably down to about 1500. The idle was iffy before, so it must have been the rings. The compression did come up quite a bit with the new rings.

Wish it would quit raining every weekend so I could fly.

Anyone ever try converting a CS-302 Echo? I have one in decent shape I think.. I believe it requires cutting the case off the outside. Trimmer engines are easy.. this thing looks like a real project.. maybe better off making a new crankcase for it.. there are no places to even start making bolt holes for a mount.
I plan on using my CDI board with it. If anyone has tried one of these 30cc motors, I'd like to hear from you.. Thanks

John

I have one. I ran it on Gas/Glow.

I used a regular motor mount to mount the engine with.

I stopped working on it when Scott Brinelli I think his name is said the power was disappointing.
I'm sure it has More potential than a 32cc Ryobi

Scott at one time was doing a lot of conversions commercially.
Anyone know what happened to Scott? He developed diabetes and that's the last I heard.

Final report,

Bambula 22x8 7200 rpm It pulls 21-pounds on a spring scale tied to the tail

TBM 21x8 6800 rpm 23-pounds

top flight 20x10 20-pounds

The Big Bee weighs 23-pounds, If I can loose a little weight It might just hover.

Hey, those TBM house brand props are really nice! The finish is really pretty and the balance was perfect on the two I got. They look like a real prop, the way they are carved, I mean. The Bambulas are not quite as elegant or as well finished. I had to put quite a lot of weight on the hubs the make them balance. The blades were balanced OK though.

Ralphbf,
Theres quite a few posts in the gas engine forum about what happened.
Dont know if there still there.
But basiclly,
Diabetes,poor vision.
Ordered a bunch of echo parts,got ripped off i believe.
Then he was suppose to build more engines,ect for people but couldnt.
i dont know if they ever got there money back,but he filed for bankrupcy.
His partner,Mark Brill,was making some aftermarket parts for the conversion engines under the same name basiclly but i havent been to his site in a year.
The last time i talked to Scott i ordered some carb rebuild kits he had for sale and after that i never heard from him again.
I traded him 2> 33cc poulans for 1>42 cc becuase he wanted to se how the 33cc poulans compared to the ryobi,but never heard back.