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Old 04-13-2008, 05:07 PM   #16
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is your flywheel attached now? if it is and you didn't pull the crankshaft forward when you installed, the back of the crankshaft/connecting rod could be rubbing on the backplate
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Old 04-14-2008, 04:56 AM   #17
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the piston not fitting threw the top of the sleeve is normal because they run a tappered bore to make compression seeing as they dont use rings

did its spin freely befor u put the backing plate on

also chech that u have every thing the right way in and that u havnt got the backing plate on the wrong way
No, this is different. I know its supposed to get a little tight, but this is not that kind of "stuck".

Looking in through the back of the engine (backplate): When the Crankshaft is going from 1 to 11 (like a clock) it gets stuck up there and moves freely, something definately not right, id just like some opions before I go taking stuff apart myself and possibly break something

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is your flywheel attached now? if it is and you didn't pull the crankshaft forward when you installed, the back of the crankshaft/connecting rod could be rubbing on the backplate
No, its on its way, I think I posted a link, was that the right kind of flywheel... I noticed they had a few different sizes

I never took the crankshaft out, I tried for literally 4 seconds, but it didnt quite work so I quit. Didnt want to break anything, Zip-Tie trick wasnt quite working.

Everything in the backplate is put together properly, is there even a way to screw that up, LOL, its pretty self explanitory... mine is even lubed up and cleaned.

I think it is something causing a lot of friction when I put the backplate on but I cant figure out what it is!!!

Thanks a lot for the answers guys... people gave up on my thread for a second there.
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Old 04-14-2008, 05:29 AM   #18
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When the Crankshaft is going from 1 to 11 (like a clock) it gets stuck up there and moves freely
how does it get stuck and move freely?

have you ever had an electric rc before? it sounds like that may be a better bet for you
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Old 04-14-2008, 05:49 AM   #19
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no offence bud but sounds like ur in way over ur head. best sit this aside until u know what ur doing and get a new cheap engine. Buy the cheapest u can get an discard it when it breaks. good luck
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Old 04-14-2008, 06:08 AM   #20
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As stated earlier the piston sleeve is narrower at the top. If it is tough to turn at the top that is a good thing! As you turn the flywheel counterclockwise the piston will get very tight. With the backplate & head off , watch the piston travel as you turn the flywheel. It should be loose when the piston is at the bottom of its stroke and tight at the top (where it gets tighter). How old is your engine? As the engine runs, it gets hot and the metal expands. You want it to be tight to keep compression in the engine. If you want, you could heat the engine will a heat gun, and then try turning the flywheel, (use gloves or a towel) it should be looser.

You might check that the piston is in correctly, usually there is a half-moon cutout that goes towards the exhaust port.
Also check how the shaft turns without the conrod & piston in the block. If your front bearing is not seated completely if could cause the shaft to have a little wobble. If that is the case it might cause the conrod and piston to bind.
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Last edited by C&B RC; 04-14-2008 at 06:16 AM. Reason: more suggestions
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Old 04-14-2008, 07:05 AM   #21
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You might check that the piston is in correctly, usually there is a half-moon cutout that goes towards the exhaust port.
This is BAD advice!

The "half moon" goes toward the FRONT of the engine to clear the crank body when at BDC (Bottom Dead Center)...try not to confuse the guy please.
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Old 04-14-2008, 03:47 PM   #22
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how does it get stuck and move freely?

have you ever had an electric rc before? it sounds like that may be a better bet for you
No, I know what im doing, electric are no fun. Im good with engines and stuff, nitro is pretty easy (for me) for the most part, its just this one thing I cant figure out. Ill take a look at it on my days off and see if i can figure it out.

And what I meant was, getting it from 2 to 1 o clock is very very hard, then it spins very very easy from 1 to 11, then getting it from 11 to 10 o clock is very very hard. is it supposed to go clockwise or CC?

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no offence bud but sounds like ur in way over ur head. best sit this aside until u know what ur doing and get a new cheap engine. Buy the cheapest u can get an discard it when it breaks. good luck
Nah, I know what im doing, this has just got me a little stumped. Im a 20 year old guy, pretty smart too, Im not some 10 yr old kid who doesnt know what hes doing, Ill figure it out, its a tough one though!


Any info on my flywheel? Will that one I ordered fit?
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Old 04-14-2008, 04:55 PM   #23
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no offense but if you're "good with nitro" then you would know that the pinch you are explaining is something that all nitro engines require in order to run correctly. most engines are extremely tight as you are explaining until you break them in, even then they remain tight for gallons until they are completely wore in, in which it is time to rebuild....

how did you break the engine in? is it even broken in yet? it sounds to me like you took it out of the box and expected to play without first breaking in the piston and sleeve.
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Old 04-14-2008, 11:17 PM   #24
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1.the clutch nut is tight, I know because it WAS coming loose a few times, so this last time (a week ago) I sealed it down with Blue Loctite! you could be right though, I definately need a new flywheel.

2. the engine is about 4 months old, ive ran about 1.5 gallons through it. I dont know if they NEED to be replaced, but I think its about time, itll make tings run smoother, maybe. And when I look inside the engine from the back (i have the Pullstart off) i can see the beads of the bearing... isint there supposed to be some shield there? I wish the instruction manual would tell me the dimensions. I will search online later when I have more time.

3. I dont think this "stuck" im taking about is a pinch, although i hope it is. It almost seems to get "jammed" up there, maybe im wrong, but it doesnt feel like a "pinch stuck" it feels more like a "somethings bent inside my engine or something" stuck. I hope im wrong....

Very very good advice with the zip tie, I would have NEVER figured that one for myself. I'll try that later tonight, let you know how it works.

thanks a lot for all the help Adrian

Carl
hey carl,

it sounds like your getting yourself pretty wound up over things that are supposed to be happening, your engine sounds like it is still quite tight and has a lot of pinch (this will ease with more running) so for it to get "stuck" at the 1-2 o'clock area is normal this is called Top Dead Centre or TDC and the free area is bottom dead centre BDC.

to me your problems have all started from a lose flywheel that has chewed out the collet you shouldn't need a new flywheel just the collet.

my suggestion to you would be to replace the collet and make sure that the flywheel is tighter than a Nun's perverbile and try that out before I would attempt to replace bearings or pull any more of the engine apart

1 more thing make sure that your backplate is on correctly and you may find that when you attach your flywheel that any tightness caused by the back plate may go due to the crank being pulled forward when tight

hope you have a bit more luck

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Old 04-15-2008, 04:48 AM   #25
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Quote:
Originally Posted by salteen View Post
no offense but if you're "good with nitro" then you would know that the pinch you are explaining is something that all nitro engines require in order to run correctly. most engines are extremely tight as you are explaining until you break them in, even then they remain tight for gallons until they are completely wore in, in which it is time to rebuild....

how did you break the engine in? is it even broken in yet? it sounds to me like you took it out of the box and expected to play without first breaking in the piston and sleeve.
Hey, thanks for the answer.

I KNOW what pinch is. What im experiencing it NOT normal pinch. Its something different, ill try to get a vid tomorrow.

I think it has something do with why my backplate wont go on properly either, I still havnt really had time to take it apart and take another look. On Thursday I will.

And its been broken, im not an idiot , I broke it in properly, Ive had about 1.5 gallons through it. Used it for bashing only, Pretty much stock tuning, it seems to run perfect.
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hey carl,

it sounds like your getting yourself pretty wound up over things that are supposed to be happening, your engine sounds like it is still quite tight and has a lot of pinch (this will ease with more running) so for it to get "stuck" at the 1-2 o'clock area is normal this is called Top Dead Centre or TDC and the free area is bottom dead centre BDC.

to me your problems have all started from a lose flywheel that has chewed out the collet you shouldn't need a new flywheel just the collet.

my suggestion to you would be to replace the collet and make sure that the flywheel is tighter than a Nun's perverbile and try that out before I would attempt to replace bearings or pull any more of the engine apart

1 more thing make sure that your backplate is on correctly and you may find that when you attach your flywheel that any tightness caused by the back plate may go due to the crank being pulled forward when tight

hope you have a bit more luck

Adrian
Hey Adrian, I know what TDC is, and by now my engine should be a little looser, Ive ran 1.5 gallons through it. I said before, this is a "weird stuck" NOT a "pinch stuck". I know what the latter is.

And its too late on the collet thing. Ive already ordered a whole new flywheel! Should be here next week

Will the one I ordered fit? I posted a carolinasrc link above. Let me know if you cant find it and Ill repost it.

My backplate is on right, Ive been having this problem for quite some time now, I cant tighten all the screws real tight or else it doesnt let the engine spin AT ALL. Kind of weird, Ill have to take a closer look at it when I have more time. Maybe Im getting too worked up and its something super simple thatll take me 2 mins to fix.
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Old 04-15-2008, 10:50 PM   #26
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Hey guys, I think i figured out my backplate problem, Ill have to wait to drive it before I can tell for sure.

Can anyone help me with my flywheel/collet problem?

And im also having troubles with my second buggy, Its been outta commission for 4 months, and I just for it running today. Problem is that when I let off the gas, it dies, it wont even idle, its ALWAYS got to have the throttle open a little but, why is that? What needs to be adjusted?

Thanks.
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Old 04-15-2008, 10:59 PM   #27
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hey carl,

sorry for the whole discription but I didn't know your experience level so thought it would be best to start at the begining.

I can't tell if its the right flywheel as I dont know what car it's going on but unfortunatelty it looks like it doesn't come with a collet as I can't see one in the pics.

without seeing pics of the back plate pull start etc I probably can't help you out anymore than I have.

but as for pinch some engines can take a lot longer to lose their metal pinch than others for Example my first GO tech took over3 gallons before it stopped getting "stuck".

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Old 04-15-2008, 11:04 PM   #28
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Hey guys,

And im also having troubles with my second buggy, Its been outta commission for 4 months, and I just for it running today. Problem is that when I let off the gas, it dies, it wont even idle, its ALWAYS got to have the throttle open a little but, why is that? What needs to be adjusted?

Thanks.
could be a couple of things either

#1. the idle is set to low

#2. the lsn is set to rich and the engine is loading up

#3. a combination of both

#4. it could be a clutch problem bearings shot
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Old 04-16-2008, 01:21 AM   #29
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hey carl,

sorry for the whole discription but I didn't know your experience level so thought it would be best to start at the begining.

I can't tell if its the right flywheel as I dont know what car it's going on but unfortunatelty it looks like it doesn't come with a collet as I can't see one in the pics.

without seeing pics of the back plate pull start etc I probably can't help you out anymore than I have.

but as for pinch some engines can take a lot longer to lose their metal pinch than others for Example my first GO tech took over3 gallons before it stopped getting "stuck".

Adrian
Thank you so much for the answers, its ok you assumed I am a "noob"

It is going on a MBx5 buggy, I sure hope it has a collet because thats all I need!

Ive got the backplate thing sorted out, I think...

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could be a couple of things either

#1. the idle is set to low

#2. the lsn is set to rich and the engine is loading up

#3. a combination of both

#4. it could be a clutch problem bearings shot
1. how do I make it higher, is that clockwise or CC?

2. dont think so, it was running way too lean, so I opened it a full turn (two half turns with tests in between) and it seems to be running fine now, except for the idle part.

3. possibly

4. dont think so, its got new bearings in it.

Thanks Adrian
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Old 04-16-2008, 06:28 AM   #30
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Pullstart motor in an MBX-5 is a no go. I'm pretty sure it just wont plain fit.

Don't try and turn the motor over without a flywheel attached, you'll never turn it over. My fully assembled Nova can only now be barely turned over by hand after almost 3 gallons, I would expect your motor at 1.5 is just pinching up.

Can you at least disconnect the conrod from the crank? If so, then try to spin the crank, if it's fine, then you're just experiencing mega pinch.

Order the collet that matches the flywheel, you need to make sure the taper on the collet is the same as the flywheel. Place a thin shim behind the collet to ensure the clutch nut tightens all the way.

My biggest piece of advice is get to your nearest track and ask someone there, it sounds like you're in the deep end and without actually looking at it, there's only so much people on here can do.
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