deadmancourt

iTrader: (11)

i just started having runaways! i can run practice then charge it,then run a qualifier then charge it,and then usually during the 2nd qualifier it starts glitching...but i start to notice my steering starts glitching first then 5 mins later or even sooner the throttle goes wide open so i always get to it before it actually runs from me!i have a REEDY 1600mah nimh hump pack that is a couple months old...a couple racers said it was cause i never let the battery run down before i charge it! i just wanted to completely avoid runaways so after every use i charge it!....is that not good for the hump pack?...somebody else also said it was cause i charge it @ 2 amps instead of 1amp...my manual for my charger says 1500mah-2100mah charges @ 2amps?....is this wrong?

jmaxey51

iTrader: (7)

first of all 1600 mAh batts will go an hour, i run my quals then top off for main and they have never failed me. also i never go over 1.5 amps on charging. but since its doing that throw the batt away, you have a bad cell. i will only run Stickman packs but all are about the same. people say if you take your mAh and divide it by 1000 = max amps it should be charged at. like 1600/1000=1.6 amps max.

jeff_ellis_9

iTrader: (5)

nope. didnt take glo plug out. I didnt know you had AR oil in it! Oops. No big deal tho. Im sure the AR oil should be gone now tho, I did run it a little bit. I have a new plug in it now. I just had a guy to shim and seal it for me thats good with r/c engines, and he used to run Nova. He said it seemed fine by looks and feel, and we had it somewhat apart. He said compression felt right. Got my new servo and Rx pack, just waiting for new turnbuckle rod ends and I can re-test this thing out. I will get back

jmaxey51

iTrader: (7)

yeah i told you about the after run oil but i guess you forgot but why did he add a shim? it was already shimmed for 30%.... it will be slower. also the engine is probably really rich, i ran the bottom end a little rich because i didnt want to harm it because it was still breakin in..

dreaux

iTrader: (5)

i stretched a rod before and it drove me crazy until i finally figured it out. The thing is, there really is no symptom when this happens. No air leaks, lots of compression, bearings and seal are fine, no slop on the pin and so on. But i will tell you, if you have a bent or stretched rod your engine will run worse then you can imagine. Complete and total crap. You will think you just put water in your fuel tank.

dreaux

iTrader: (5)

go catch it.

jeff_ellis_9

iTrader: (5)

jmaxey, did you shim it yourself? Or are you saying it was shimmed from factory? I have no clue the guy just told me that they run better when you shim it and get better mileage. But I will run it and if its alot noticeably slower, then I will take the shim off. (I can do that right?, like will it mess anything up?)

jmaxey51

iTrader: (7)

i had it shimmed correctly. and if you get any better fuel mileage youll be getting over 10 min a tank. i was pitting at 8 min 30 seconds to 9 min with it. the engine was getting killer run times. i had a couple tanks in practice getting over 10 min then in the race a was getting a little over 9 min

jeff_ellis_9

iTrader: (5)

Oh ok. I didn't know you had did anything to the motor. It won't hurt that he has shimmed it will it?

I guess I could just try it out and if it runs fine then I will leave the shims he put in there in, but if not I can just take them out right?

latemodel13

iTrader: (101)

If he had it shimmed for 30% and you run less nitro it can make it hard to tune also. If you added a shim take it back out and if your not running 30 % take an additional .1 mm out and it will be easier to tune.

jmaxey51

iTrader: (7)

i would try it and see, he might know something i dont know about it. it should be fine. i had a GRP that was shimmed for 30% and i ran 20% for a long time with it and had no problem, made it a little smoother on bottom. i switched to 30% after the 5 gallon. but with him shimming it, it might make it a really smooth powerband which in return makes it easy to drive.

deadmancourt

iTrader: (11)

i have a nova 21 that was shimmed to run 30% but i only run 20%....should i remove a shim?...or just leave it alone?....i had it tuned great and now it is just a little wild on the tune...i wont hold a steady tune! has tons of pinch and was professionaly sealed up! everything on this motor is sealed! i have a mach.26 that has no sealant except the stock o rings and such,and it holds a tune great! and is much older!

jmaxey51

iTrader: (7)

your rubber dust cover might have a pin hole in it and it would make the tune un-predictable. but personally i would leave it shimmed for 30%. all my engines except one is shimmed for 30% regardless of the percentage of fuel i ran. but you could try running 30% on your next gallon.

deadmancourt

iTrader: (11)

that does make sense! is there a way to seal the rubber boot on the lever side?...it is starting to show a tiny bit of fuel!...the boot to carb side is sealed!

Zerodefect

I'd tear it down. Check the rod for play, it's probally toast. GO has cheap rods that may fit. My N21's wasn't nearly as tough as the usual RB/NR rods. Check the piston and sleeve for scoring. Pop a fresh plug in and give it a try with fresh fuel.

Then just get another N21b and keep this one for parts. Afterall it's only a $180 engine, not worth buying a piston/sleeve for.