hicheef

Kind of a noob question but it's my fourth nitro motor and none before have done this. Probably just my first good motor. Anyway, MR12 just out of the box. Mounted it, soon as I put it on the starter box I guess the compression just locks the flywheel up and no start. I can't get it to spin long enough to prime the fuel line. It locks at first hit. I have to push and push on the wheel by hand to unlock it. try again and its the same. Any input?? Thanks for any help y'all can lend!!!!!
Kevin

rrgt_kid

take the glow plug out with fuel in the tank then prime it then put the plug back in and then try again!if that doesnt work try loosening the plug a 1/4 to 1/2 a turn to get it started. you could adjust the throttle stop srew to make the carby open a bit once you got it started then put it back to where it was.!

jeremy

hicheef

How do you prime it with the plug out. Feed fuel directly into the cylinder?? Thanx for the reply!!!
Kevin

Bobby Flack

When you have the plug out, or loose, you can spin the engine over very easy which will prime the engine. New engines are very tight so they are hard to spin over.

hicheef

Very cool, loosened the plug, heated the motor with a heat gun turned right over for the first tank. NEW PROB. The idle for the first minute of the tank is fine really smooth no prob, after the first minute the motor starts to really get racey, starts to rev to the point the clutch kicks in and the wheels start to spin, at times pretty quick. As well the temp is between 245- and 250. I haven't touched any of the needles. any ideas, I know I have to get that thing cooled down!!! THANKS KEVIN

alucard13

my mr12 was broken in by my friend, but i do know that if your clutch starts to engage during idle, you may need to decrease the idle rpm (not sure what screw that would be though). My hpi rs4 had that problem where the wheels would start to spin at idle and i had to adjust the idle screw. just be careful cause you dont want to turn to much that your carb goes in when braking.

you might also want to check to make sure that the fuel line isnt getting clogged after the engine warms up. cause if it isnt getting enough fuel it may be running to lean and causing the engine to get too hot.

i'm a noob as well, but i'm learning and i'll try to help as much as i can from my own experience and what i've learned from these guys

bt

had this problem with a new mr12 that i brought what we did was pulled the motor out of car cracked the glow plug and pushed the fly wheel against the bump box and let it turn over at 30sec to 1min intervals continously adding after run or fuel to lube it,it worked fine when we put it in the car hope that helps.

Im2lazy

Personally, I prefer to 'run-in' my engine as opposed to 'idle-in' my engine, but from the sound of it, you might want to richen the low end. After time, a too lean low-end needle can cause the engine to build up to much heat, as well as cause the engine to pick up rpms.

rod_b

When I got my MR12, I thought the needles were so outta whack that it would never get started. Seemed overly rich. I set the needles to where I usually start tuning a broken in engine and it started up just fine. No bogging, no flooding. After a min or so, it started to heat up like yours did. I just richened up the main needle when this started happening. Eventually, I ended up where the needles were to begin with. I think the engine just needs a bit of help at the beginning to get started. Once you've got it going set it back rich, then start driving it around. That's what I did and my engine has been more than satisfying.

hicheef

So you think richen the main needle not the low needle for the high temp at idle will bring things down?? THANKS!!!!!!
Kevin

Old Skool

Actually, since you're beraking in an ABC engine you want some heat into it, or else the engine will never reach its optimum performance. Try and keep the temps in the 220-240F range. When I get a new engine, or rebuild one with a fresh piston and sleeve, I usually either leave the carb needles at factory default settings, or reset them to factory settings (respectively), and idle one static tank before driving the car under load. Remember to change out the glow plug before driving it, too, since the one used for break-in gets contaminated from the residual particles.