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Mugen MBX5 Prospec Thread :)

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crzy-svg-usr said:
699 from southeast rc
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That's my LHS those guys rock....I bet if you call and speak to them you can get it cheaper......tell em you are looking for a good RC supplier and you are going to spend many dollars w/ them if you like them......
 
Ok got the email back from o.s. They are telling me to get a hand starter. I hae seen them for planes but never cars. Any got a link to a decent one?
 
Hypedonrc said:
You don't live in Ohio do you? I know a guy with the exact same story.
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crap you found me out... :jk:

seriously, I live in PA. I guess your friend and I think a lot a like. :)

PiErow, "hand" starter?? Sounds like you got someone that gave you air plane engine advice. EVERYONE uses a starter box for 8th scale buggies. Out of curiousity how are you charging your gelcel starter box battery?
 
big freak i just got a wallcharger but i havnt charged mine yet lol i dunno how to charge these either and didnt wanna mess it up fast charging it so i got a hobbico wall charger


and on a side not anyone use a personall transponder? know where i can get one for a reasonable price?
 
So they don't have to deal with the problem. Lazy customer service. If the box is turning the engine over in the right direction, then the box is not the problem.

Are you SURE your box is spinning the right way? Like they said, if your left hand is on the front of the buggy and your right hand is on the rear, the top of the starter wheel should be turning towards you.

The glow plug works, we already know that.

Is the engine getting fuel? Remove the glowplug. Rest a Kleenex on top of the engine head, plug the exhaust stinger, and crank the engine over at full throttle. Getting any fuel on the Kleenex? If yes, you'll know it's not a matter of fuel getting to the engine. (Be sure to drain the excess fuel from the engine before re-installing the glow plug.) I've seen plugged carburetors, and plugged pressure nipples, both causing starting problems.

As long as the engine's turning the right way, your glow plug glows hot, and the engine's getting fresh fuel at the right mixture, it should start.
 
You may also want to check that the carb is in tight. Though usually if it is loose it will still run, just lean. There is a little screw on the engine block that tightens around the base of the carb. If it is loose it will suck air, and mess up your air/fuel ratio. Also, just for the sake of checking it, git the head bolts a little twist. Just make sure they are snug. Don't go putting the Hercules on them. Last thing you want is a broken off head bolt.

What did I find just after mensioning the possibility of the carb not being tight but this.
https://www.rcnitrotalk.com/forum/showthread.php?t=27504

Maybe it's a sign! LOL!!!!!!!!!!
 
PiErow, did you try giving it a little throttle while starting it up for the first time? It's gonna come pig rich from the factory. Chances are it isn't going to idle. If it doesn't idle then it won't start on the box without some throttle.

To charge the gelcel battery, take 7000 and divide by the charger output in mah. So if it's a 500 mah charger, expect it to charge 14 hours. (7000/500 = 14) You'll also know it's charged when it gets warm. Do charge it faster than 2 amps or 2000 mah.
 
Okay refreshen everyones memory...
I have gotten it started once and ran about 1/4th tank on it. Everything is fine. However the piston locks at top dead center and has to be pryed out. My boxs dont have the power to turn the engine when it locks. I charge the battery over night and is putting out 13. point something, so its fully charged. The hand starter has more tourpue then the box. I will let you guys know how it goes!
 
Heat up the engine before you try to start it. You can use a heat gun, or failing that, a hair dryer.
 
Use a flat head screw driver to gently turn the flywheel, and get it off of TDC. Everyone has differand break in proceedures, but IMO the best is to just let it idle (or barely above if you have to to keep it running) ontop of your starter box for 4-5 tanks. All this time checking the temp, and adjusting the carb settings to keep it over 200, but under 220-225ish. THen you can putt it around. No more than 1/4 throttle. Maybe a short 1/2 throttle blip or to if it seems to be running good, but I wouldn't (no matter how much you want to) for another couple of tanks. Keep checking the temp, and adjusting the carb to keep it in this temp range. I also tune by ear a bit, but if you aren't very good at that the temp will keep it close enough for break in. As the engine seems to get more power, and the adjustments needed on the carb are less to keep it in the temp range you can start to give it a little more gas a LITTLE longer at a time. In between each tank let the engine get down to at least 150, and as always use you fingure, screw driver, what ever to make sure the piston isn't TDC when not in use. It took my OS MAX VZB around 1/3 of a gallon to make it to 2 seconds of full throttle, and the better part of a whole gallon to be fully broke in.

I forgot to mension that it should be at least 45, or so outside. Under that it's too hard to keep the temps up for proper expansion of the engine metals without leaning it out too much for safe oil content. What fuel are you using? It should also be one of the higher oil content. Not a race blend!
 
PiErow said:
My boxs dont have the power to turn the engine when it locks.
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No box or hand starter can turn an engine when it gets stuck like this.

Hypedonrc said:
Use a flat head screw driver to gently turn the flywheel, and get it off of TDC.
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This is what I do if an engine gets stuck durring break in.

To avoid the problem, get the engine up to temp with that heat gun you have and then keep it there by wrapping the head while doing the break-in.
 
Ya the heat gun really does help a lot. Its not me havin the problems. My dad doesn't have the paitence and since he hlped fund the mugen i do things his way. I honestly dont think the hand starter will do a damn thing. I just waiten for him to give up. Then i move in and get her runnin...

Did not read.
I'm running odonnel 20%.
Also what do i rap around the engine to keep it warm?

My break in procedure plans to go as fowwolows

Tank 1-5 = Idel
Tank 6-7 = 1/4 throttle figure 8s
Tank 8-9 = 1/3 throttle figure 8s
Tank 10-12 = 1/2 throttle figure 8s
Tank 13-16 = 3/4 figure 8s
Tank 17-18 = 3/4-full 2 secound bursts 3 secound no gass, straight line
Tank 19 = same as above but 5 secounds on 3 secounds off
Tank 20 = Fun begins!!!!!!!!!!!!!!!!

Also when i try to start I'm giving it almost full throttle to get her fired up then i back off to half, this is the only way i keep it running. I only did this once(only time the engine fired up) for about 20 secounds, then as soon as i let off the gass (went down to 1/4) she died, and i could not get it going again.
 
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makes you wonder if there something wrong with that v-spec, all the ones I've seen have are almost runnin with very little pinch straight out of the box, 3-5 tanks just for oil penetration and theyve been roaring !
 
My OS MAX VZB never had alot of pinch compared to most engines, but it still gets stuck TDC sometimes.
 
PiErow, you can wrap the head in aluminm foil or aluminum tape. I personally found that those squishy foam beer cozy things can slip right over the head and you can keep it in place with a couple of rubber bands.

PiErow, is your dad resistant to the idea of using a straight blade screw driver on the flywheel to back the piston out of the sleave? It's really not a bad thing to do. The engine isn't gonna budge util you get it unstuck.

well, good luck with it
 
i have a little question. i was out practicing today mbx5, ws7II carbon shoes trimmed with 1.1 springs, anyway the clutchbell was super hot and discolored. never had this happen before, was the reason being the clutch slipping? the engine did not over heat, and i noticed when i took it down one bearing was GOING bad, it was not apart or anything but both bearings were discolored. thanks
 
yes mine did that too and the only way i got my clutch to stop slipping was by making my springs 1.0 my ws7II still runns perfect with this clutch setup and the shoes dont slip at all now

if u hear a weird whinding noice when u hit high rpms (thats hwen mine slipped) u know they are slipping just listen
 

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