ok guys please help, i can't figger out why this engine isin't running correct. Once i get it started, and up in the air about two or three feet, the engine starts to lose power and it falls to the ground not hard but just gradually enough to where i can give it full throttle it wont stay in the air. this happens after about 40 - 45 seconds of run-time(including a 20-25 second warmup). I try to adjust the needle settings a little leaner thinking it's too rich, then it runs good for about 15 seconds and falls on it's face again but it dosent die. It won't hardly even run if i richen it up, so that is not an option. So..........i figger i have a worn out engine, no prob, i'll just go and buy a new engine. Got it, and now i have the same problem. Now i think i have a fuel tank problem, got a new fuel tank. Still the same problem. Exaust is good, no problem there. New fuel line, new glow plug, changed head shims to one, two, three......no shims seems to work better than any.

My elevation is 675 feet.
It is about 70 F degrees outside
i am using powermaster fuel (prolly not supposed to)
15% nitro (i think this may be my problem)

I hear that these little engines like high nitro pecentages, I'm not real sure of what kind of fuel to use but powermaster is the only fuel available to me at the moment. I have to order any other kind of fuel and that gets kinda pricey when you have to buy bulk.
I can get my hands on 30% powermaster......will this higher nitro mix fix my problem??? I think i have done most everything I can to get this little motor running but i have failed to achieve it. now i am asking for help!!!!!

THANKS!!!!

Joe

I use at least 25% and make sure gear mesh is good and smooth.
You may have a bad bearing.
Poor blade tracking, and vibration are power killers.
It sounds like it is over heating because of friction some were.
If it is losing power during flight it is over heating. This is the biggest problem with the V-max6.
Hope this helps, and if it get over 79 degrees out side hang it up.
Joe

heres the skinny on the vmax 6 engine. Ive been through it all and then some. the Vmax 6 engine loves to be tightly sealed in order to run correctly for the LMH helicopter. As the heli engine heats up, something is expanding and is causing a leak somewhere. Ive done it and others also, we put a little blue locktite on the threads of the heatsink and what did ya know.... Ive found out that its ususlly a leak somewhere that will cause a power loss. Things to check: Check screws for tightness on cylinder, check backplate, check muffler, check Heatsink. If your engine is tight as it can be and it still dont produce power then there is the compression (adding and reducing copper rings). It actually takes a while to wear out one of these engines. I run my engines both V6 and V7 with 15% fuel with no probs at all. My personal opinion on the V6: Its a headache to tune but once you find the right settings for the engine, they run fine. As far a for the LMH Heli, I think the V6 is borderline sufficient power for the heli. Now, The V7 engine It opens up another world for the LMH Helicopter. It has ample power for the LMH Heli. when descending and you get caught in that down wash from the rotor wash and you are falling like a rock, you can actually throttle up out of the down wash, even at low altitudes. You'll have good power to loop (Its not just pulling back on the sticks) It a technique you will have to learn with the fixed pitch light litemachines heli. hopes this will be of a help to you.

What you were saying about loosing power and then leaning it out makes me think that your running too lean. Does the engine run un-evenly? I suppose the situation is that your fuel wont make the power at the proper mixture setting, so you have to lean it out too much to fly. Then the engine starts to overheat and then looses power.

I'd say, do what darth said. A loose backplate caused me headaches for a while once... If you still have the problem after that, you really should try a diffrent fuel.

Good luck!
Rico

Hi Joe,

Like Rico said: Sounds to me as though you're running too lean. A lean engine over-heats and grinds to a halt. Unscrew the needle until you're running as rich as the engine will stand, then turn it back in, gradually, until the heli can lift-off. You need to run rich enough so's to keep the engine cool, but lean enough so's you have sufficient power. With this engine you don't have a whole lot of power to spare, so you have to get this right

Also like Darth said: Use blue Loctite on the cylinder head threads - doing this completely transformed my V-6

I couldn't get away with 15% nitro so went to 30% which worked great. Over time I've reduced the nitro content and found that 20% is the lowest I can go and still keep my LMH flying reliably

Good Luck,

Tony

I had to get an extended tank for a plane I'm building..you can get a quart of norvel fuel for like $10...from the shopatron Norvel site..I went ahead and got a quart (%35 nitro) when I ordered just to try.... I have been running cool power %20 in my Norvel. .049 and .061 plane engines,, I havent done anything with my heli in a while...but am thinking of putting a .15 os engine in it one fine day if I ever get the time

cool guys, thanks for the support!!!! I'm gonna try the backplate thing. I went to the hobby shop today and they were out of everything but 15% fuel. so I looked around for some other things and found all the stuff i need to convert this thing over to electric. a buddy of mine flat out gave me a brand new Team Kinwald 600-10 turn motor for free. I found a decent ESC and a pinon gear and some extra wood to mount it on. Had a couple of battery packs laying around so I will give the MAX-6 one more shot with the max-6 before i transform to elctro powered. I have had about four people look at this thing and they gave up so I'm starting to lean toward the electric side of things.

KLRICO......the engine runs totally un-even. It will run good at a hover rpm for about 10 or 15 seconds and then it looses power.
it will never die but when i bring it back to an idle, it idles very irratic. If i richen it up ANY at all, IT WILL NOT gainanyRPM at all. It just sits and gurgles. If i lean it about a quarter turn or so it will have plenty of power for about another 10 to 15 seconds. I just don't know what else to do. I seem to think that 15% nitro is very sufficent because it ran REAL well the other day for one full tank. I hovered the whole tank because i havent got the concept of FF just yet. (havent had an engine working right to get my confidence up)


THANKS TO ALL VERY MUCH.........I will let you all know what happens


Joe

did you take the needle valve completely out and back flush the fuel line ?

already thought of that one too darth. thanks for the thought. even put a fuel filter on it.

Joe

Lite machines has recognized a problem where if you tighten the needle valve too much you will cause it to become deformed and not function correctly.

[link=http://www.litemachines.com/Downlds/TechBul7.pdf]See This![/link] - Maybe this happened to you.

Rico

You're right Rico - this happened to me too. A file cured this little problem for me - it made tuning the engine possible!

Tony

Tony - Did you simply file out the shouldered part, and that solved all your tuning woes?

I had figured that sort of thing would cause the sort of problem originally described... Being either too rich or too lean.

I hope that works out for you.
Rico

Hi Rico, Yes you can just file the needle back to its original shape. This will obviously make the needle a litle shorter. But then you just turn the needle in a little more to compensate (it happens sort-of "natruly" as you tune the carb). The needle is made from very soft metal so the damage very easily happens, and is just as easy to cure!

Tony