Been looking around a little bit and this post prompted me to join so I could lend a hand. I own a dle35Ra as well as a friend. Mine has 4 gallons or so through it and my friends has 3/4 throught it and his is yet to be maidened.
I broke in my engine on test stand as well my friends with 30:1 Maxima Castor 927 blended castor/synthetic racing oil from the dirtbike shop. First thing I did was throw away dle spark plug and install an ngk cm6 and ive found from both engines that .020 is the happy spark gap.
The manual stated 2 hrs at 4400rpm break in with 30:1. That tells me compression is low from the start and it needs a good break in to be reliable so why would I want to fly an unreliable engine till its right.
I went with 15 to 20 minute runs tuned burbling rich and spitting lots of black gunk out of exhaust. I would run about 3500 to 4k rpm for 2 or 3 minutes, clear it out with a 2 or 3 second gradual open full throttle pull then back to 3500/4000 then idle down to around 2k for a minute, then back up to 3500/4k range and repeat. After first 15 or 20 minutes the engine has changed for better already. Let cool to ambient temp with a fan blowing on engine to speed up the wait time.
Start up and do it all over again but the second run will need a little leaning and subsequent runs after will need little needle tweaks too as the extra gas/oil becomes less needed as ring is sealing.
Both engines run amazing broken in this way and after break in I switch to 32:1 redline synthetic. Lots of black gunk will come out the first tank of redline so the test stand is a good idea for that. My plane was covered so we did that to my buddies to clean internally the leftover castor goo before taking off test stand.
Mine will spin a vess 20A (20x8ish) at 7700 to 7800 on ground and the Vess 19A (19x8ish) at 8100 on ground with one field about 5200 ft asl and the other field about 3600ft asl with a minor needle change between elevations. The yet to be maidened one will spin the 19A 7800/7900 rpms as its still breaking in. My max performance didnt come till about an hour in the air afer the test stand but its been reliable and a total powerhouse from first flight.
LASTLY and VERY important.
I run fiji bottle 3 line fuel tanks from wrongwayrc.com. fill line, vent line and ceramic filter clunk line strait to carb. No inline filters or tees with fill lines on feed line to introduce air leaks or trapped bubbles.
The ceramic filter clunk or walbro felt clunk is crucial from what ive seen on test stand runs. Mine went flawless on test stand with my fiji tank with ceramic filter clunk, my buddies we had problems with. His fiji tank came from a different supplier and cost double but had strait through old style glow type clunks and at 3x4 tank at certain rpms the fuel would froth and it would suck the frothy bubbled fuel up the line and engine would start going lean from air pockets. My ceramic clunk in the prebuilt tank from wrongway will bleead my tank completely dry before you get air and its not a bubble its a completely dry line when it runs out of gas.
My sukhoi went down from a stabilizer failure so my engine (ran on stand after crash and good to go) is now in a factor 30cc as well that is yet to be maidened and the new broken in engine is going in factor as well. If we start having problems with them in the factors then its a cooling issue in the factor cowl and thatll be addressed and I'll report back.
I suspect half your problems are low ring seal from being new engines and the other half is fuel froth if you used stock tank in the factor as I noticed the strait through clunks that came with mine.
I did have one day that it ran like crap, needles wouldnt change anything, ended up being spark plug boot. Took off boot took circlip off, over bent circlip for tighter boot to spark plug grab reinstalled perfect. Took circlip off after, used a small automotive worm drive hose clamp installed loose around boot shove boot on till seated, then tighten hose clamp to literall lock the boot on. Works great.
I hope something in the above book i mean post help and if anything is vague feel free to ask.
Mike
Edit. How much did you cut open the cowl on the factor?
Last edited by PremixMike; 06-10-2017 at 01:44 PM.