Sounds about right !

Flyer88

Okay where is the MLD 28 performance mods thread. Anyone for a little octane booster and a hotter plug to start? I always did that to my YX80 dirt bike until I burned a hole through the top of the piston. Is their a performance modifications thread for these 2 cycle engines somewhere?

Tele1974, may I recommend for you to try APC Wide props for slightly better performance. At 14pd, it is slghtly out of the power to weight recommendation. Going to to a higher octane will improve the engine slightly. However it will increase the engine temperature tremendously.

Looking for added performance ?? Trim some fat off your plane....................

Flyer88

Been a while since I looked back at this thread but I was using a 17x8 apc prop at the time and now I'm going to try a vess 17x8 to see if they rank up to be the best from what I've heard! The plane weighs 12lbs because its running 2 2700 nimh and beefed up landing gear. I'm retiring this plane though after the summer for the kyosho spitfire 90 and am going to run the mld in that airplane (the yak is 2-1/2 years old flow solidly). I don't know how half the people that are running the 18" props have enough clearance because when i land the landing clear compresses because its so heavy, and I don't have that much ground clearance but i went and measured it with the 18x8 xoar on and got like 1-1/2" of clearance!

Trim some fat? I guess I could take the pilot out. Changed my push rods to carbon. I got a 28 gram reduction.
Other than that I wouldn't know where to start. Batts... I guess I could go down to a 1500 or go lipo. I have my batteries in the motor box as far forward as they could go. It just needs the weight up their. The landing gear could be carbon and the tail gear. Send a check or money order to the Seagull Trim the Fat fund. Your donation would be much appreciated.

I have a question. I flew at the field today and the MLD was running great today. Gets stronger every outing. I have almost a gallon through it now.

Great day other than this...

Both first and second flight today I notice what I thought at first to be air pockets causing a nudge of aileron to the left. Kept flying and it happened again. In a different spot in the field. I asked one of the other pilots to watch my plane to see if I was just seeing things. And nothing. Flew great. Landed let it cool. Checked voltages and both packs were at 6.6 to 6.7ish. Next flight. About the same spot in the field at half throttle. Their was a big roll to the left and the throttle was erratic. I just about crapped myself recovered and turned it in and glided in using all of the run way trying not to touch the stick fearing it would happen again.

If I was still on 72mHz it would have probably been a simple hit from who know what. With my small electrics I would think much of it. But with my first 25% plane... scarded the sxxx out of me.

When I landed one of the guys asked me if my throttle linkage was metal. It is all inch and a half of it. I mounted my throttle servo in up against the fire wall. So, I changed that tonight to a heavy plastic tube with dubro ball links. Another thing had alot of servo wire for the ignition power wound up in a bunch and zip tied. Just got back from radio shack with some RI chocks.

I would say change your linkage to at least some plastic even if it involves putting a ball link on. Check to make sure you spark plug boot cap is securely attached to the spark plug(this will cause interference if it is riding up and down). Other than not sure but i don't think there would be a dead spot. Also check your wires to make sure none of the insulation around the wires is cut open exposing the wires.

Sorry unfortunately i can't help I would have to see it in person.

I had interferance a couple of weeks ago and almost put her in and I'm on 2.4

I traced it to a plug cap that had a gap in the split portion of the cap and was getting radiation from there. Added a piece of wire around the cap to keep it tight and closed and havent had a problem since.

Flyer88

I went crazy with the chokes. Put them on the following. Ignition battery wire, Throttle servo wire, Ignition battery wire after switch, and the timing lead. I changed the throttle linkage rod to plastic...hope it doesn't melt...with dubro ball links. I noticed that the linkage arm to the throttle butterfly was loose and was not moving with a couple transmitter clicks. The shaft is tapered and flattened on two sides and the arm fits over it. Problem: their is too much taper. I use the dremel and shorted it and replaced the screw with a socket head. Good luck if you need to do this mod. The screw was a pain to get out. I striped it out, but finally got it out. It is nice and secure now. Mod inspired by finless bob. I had the same problem with the feathering shafts on my heli.

Muffler was the problem. I just tightened up up too. My throttle linkage came off today. It must of ran for 30 minutes before it ran out gas. It died dead center stage, turned in for landing and quickly ran out of runway. It was approaching pretty hot, I ballooned it and threw it on high rates and pancaked into a bean field. Not a scratch... Well, Broken prop and bent landing gear. I took the cowl of to inspect the motor box and repair the throttle linkage and found that a screw from the muffler worked its way all the way out the other screw was relatively tight but the threads are pretty hashed up. I may need to tap it before I reinstall it. I had the muffler off a couple of times and the manifold gasket tore. I went to the lawn mower repair shop and got a chunk of gasket to replace it. It was thicker than the paper thin stock gasket. I wonder if the heat shrunk the thickness of the gasket and loosened the mounting screws. I should have rechecked them for tightness. They shouldn't of came out anyway. I am lock tight on too.

Hope someone can help me (or point me to someone who can) with a perplexing question re. a MLD-28 that is a bear to start. Cermark (who were VERY helpful) did a test run on my MLD-28 when I sent it in for diagnosis. They video'd it running strong. I reinstalled it in my Cermark Su-26 and it still would not start. Ignition Batt was ok as was the spark at the plug. Changed the fuel tank from a three tube rig (clunk, vent and filler tubes) to a rig with new plug and only two tubes (clunk with "T" for refill line & vent line). THEN it started ok. Flew 4 flight totaling 25+ minutes. It started within 3 flips second start after the first flight too! Then at the field for the next days flight I spent 2+ hours flippiing it trying to get it to start but it only sputtered like it did initially.
When trying to start it pops after primed and IGN on and choked. But then, with choke open, it only sputters for a few flips and then stops that after 5-6 flips like no fuel is being drawn from the fuel tank. I have the fuel line secured with double zip ties to the metal tubes and the "T" Vent line seems to be functioning fine too. Is the MLD-28 real sensitive to any small air leaks in the fuel tank/tubing? How can I remedy this? Any ideas?

My engine starts as follows. Choke, 3-4 flips , sputter. Choke off, throttle trim down,4-5 flips sputter, next flip starts running rough from too much fuel . As it starts I quickly trim up my throttle to the neutral position and run the rpm,s up to get rid of excess fuel. Then she runs perfect.

How did you set-up your needles on your carb ?
What type of ignition battery are you running ?

Flyer88

I set the needles: L & H @ 1 3/4. Trim up 6 clicks. Got it to start by slapping the prop to give it a bit more RPMs. Once started I had to lean the H needle for about 500 RPM more and leaned low a bit for smoother transitions. Now it Roars!
IGN batt is a 2S Li-Po 2200 Mah run through a 6 Volt regulator. I have plenty of spark at the plug.

Save yourself a lot of flipping and use an electric starter. Close choke spin it until it pops, open choke and spin it again and she is running.

Run a 4.8volt directly to the ignition, the 7.2 will fry your ignition, even on a regulator. Trust me been there.

Flyer88