N7 105HZR extra rich settings, going lean

[Aaron T]

Hey guys, long story short, New 105HZR motor...Needles out past factory settings, chugging rich, goes lean after about 30-60secs intoIU1&IU2. VERY lean, like...stalls kills glow plug lean.  Ive had nothing but problems with this motor since the beginning. OS is being no help here, Ive had the motor apart-regulator apart, tank apart, carb apart, new fuel lines and burned up 6--yes 6 glow plugs on a motor with less than a gallon on it. RICH-LEAN-RICH-LEAN. The motor is, well, new and a total PITA.  I am positive there is no air leaks on the carb/backplate. Have LYNX MOAS clunk in the tank. No fuel dripping anywhere around the pipe (sealed great) backplate is dry, head is dry, carb and needles dry. Tank has exceptional pressure, not foaming up much..just normal bubbles. Check value seems to be working just fine.  Motor went to Hobby Services after less than a min of actual run time because the Con rod broke, destroying just about everything internally. They will not warrantee my POS new motor any longer without charging me....even though, I demanded a new one after the incident. For the price of this motor...I was hoping for a little better customer service. So here I am, looking for advice from you fellow N7 owners that run this motor/heli combo...whats next? Im lost..pissed..and totally aggravated with this $530 paperweight. I just wanna enjoy my new N7.

[Kevin Feil]

Aaron, give me a call I'll explain the resolution to your problem. (404)809-1622

Kevin

[Kevin Feil]

Sounds like you have one of the old miss drilled needle seats. You will chase your tail . I have one  (correct one) I can send you... Remove the needle seat from your engine ( one that holds the regulator on "high speed" ) compare with the pictures, see if the inner bore is big using the pics I attached. Top needle seat "lighter Grey" is the correct one. The bottom pic "Darker Grey / larger inner bore" is the wrong one. This was a problem that OS had and it follows exactly the symptoms your having. Text me a pic of the one you have when you pull it off. I will be glad to send you the correct one.

Kevin

[Aaron T]

Spoke with Kevin on the phone this morning, we have come to the conclusion that I have the correct needles in my 105 so I'm looking for more suggestions. Planning on bringing it to IRCHA to hopefully have another set of eyes on it, see if we can figure it out before I throw in the towel on it. I forgot to mention in my original post that Im running Byrons 30% Rotor Rage, that is the only available fuel I can get consistently locally. I have the stock shim plus the thicker shim added to the head per the OS manual. I tried a tank of a friends 20% fuel, with the same symptoms I'm currently having. Thanks for the phone time this morning Kevin, looking forward to IRCHA!

[Mike Spano]

IMHO it sounds EXACTLY like the regulator and/or check valve. mine has done that. I keep a few new check valves in my box, and I keep tools to clean my regulator with me all the time. clean with denatured alcohol. I also wear rubber surgery gloves to keep my oil from my skin off of the diaphragm when cleaning and re-installing.

I would simply put it in a hover in normal, low HS, like 1650 and see how long it takes to go lean. if it goes lean, replace the check valve first.

[Mike Spano]

we all make small simple mistakes, god knows I have made my fare share of them.....double check that your check valve isn't installed backwards. I have done that before myself....

[Aaron T]

It is installed correctly, I did take it apart as-well. Tank holds massive pressure too. When I had it apart last night, I blew into one side...then the other, it is working correctly. Still could be an issue, good thought. I do have another one here too try. Good idea. I took extra precautions dealing with the regulator, its clean as a whistle and as far as I know, works as it should. Unfortunately I ripped the damn fuel tank stopper grommet taking the clunk out last night to check on the clunk line and MOAS clunk. I have NO parts support here local so Ill have to pick one up at IRCHA. So Im really extra stuck here right now...Thanks for the idea Mike, I will give that a shot as soon as I can get the tank grommet.

[Mike Spano]

no problem. look, when you clean your reg, there are a few things you can do without risking damaging or losing parts too.

1) I put the cleaning agent in a squirt bottle. I will press the spring down, then force fluid into the reg from both directions. that will free up any debris that possibly may be in the little orifice. doing it that way is safer than the next

2) you can actually disassemble every little part and clean it by removing the pin and cleaning each part individually. be very very very careful not to spring the spring, or lose any parts.

dumb question - you are not trying to use locktight or rtv or anything to hold head bolts and back plate bolts in are you? if so, remove all of that immediately. I have a burned up 120 on my bench right now that I got free from a friend that burned his by using rtv in the cylinder head bolts. the rtv will not let the head seat perfectly flat on the cylinder and will cause crazy issues.

thinking outside the box. sounds like this problem may be triggered by heat (or is the issue causing the heat...). fruit for thought, keep the wheels turning....

[Kevin Feil]

Great Talking to you Aaron, the one thing that I keep coming back to is the (Head Shims) I honestly don't know what the magic number shimming is required to run 30% (.02mm + .01mm or .02mm??  , I run either 15% or 20% CP. I have run 22.5 % and never shimmed the head to add to the original shim installed. Point being, I hope some of the guys can speak to this. That is in my opinion a vital piece of information that needs to either be looked into or "Check the box that it's acceptable"  either way I will be more than happy to help get it sorted out Saturday with you. 

BR,

Kevin

[Jason Cummings]

I once had an engine with a crack in the crankcase that was very hard to see. It ran fine until it got up to temp and then would lean out. It drove me crazy trying to tune it. Hopefully this is not your issue but look it over very close especially around the bearings. Maybe even get a magnifying glass out.

[Aaron T]

There is loc-tite holding the backplate on, no RTV on the head..no way. I do have RTV attaching my muffler though. Its sealed really well. Dry as a bone. I sprayed denatured alcohol into the regulator while pressing down the pin, it was clear both times I did it. Extra clean inside both times actually. When i took it apart last night, I found that the piston sleeve is now attached to the head, I was unable to break it loose. Im sure from the heat. I didn't want to damage it by prying it off, so I left it on and reassembled it. Top of the piston is all pitted already, even though, soon as it goes lean..I kill it. Man I have this thing so damn rich. I tried to take a video yesterday at the field, of this happening but of course my RX pack was dead. I did manage to catch it a little bit, but not full lean like I am experiencing. I will put it up on youtube really quick so you can see it. Its a short clip, watch it till the end. It goes so lean...no smoke, then I kill it before it eats another plug. Video tonight.

[Aaron T]

At the end, smoke stops-HS drops right before I land. Turn up the sound. Video: https://youtu.be/QbDuYzD3vI0

[Kevin Feil]

I would stop running it with the head pitted, your going to get hot spots and it will cause detonation and then you have a really big issue, with the piston is pitted, I bet you the head is " Peppered" ? If it's bad as well your just chasing your tail Aaron. I'm curious to see if you have a head gasket leak. I wish I had the motor sitting in front of me, and the part about the Sleeve being fused to the head is interesting. Can you measure the thickness of the shims currently installed? And are you running an OS#8 plug?

K

[Rodney Kirstine]

The sleeve on mine also sticks to the head. I have to heat it up with a heat gun to separate them.

[Kevin Feil]

Well after talking to Aaron, this evening. The Head is In fact peppered and the motor is done. Time to find a Head, Piston, and other parts pending inspection. We will look at it Saturday
Safe travels

K