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Old 04-13-2003, 05:09 PM   #1
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Engine locked!!! AHHHHH

I bump started the flywheel without the glowplug in so it would prime the carb. When I did that, the flywheel froze. Any ideas? The flywheel should rotate counter clockwise correct?

What's wrong and how do I fix it?

Thanks.

Last edited by RedScorp; 04-13-2003 at 06:07 PM.
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Old 04-13-2003, 07:06 PM   #2
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Default Re: Engine locked!!! AHHHHH

Quote:
Originally posted by RedScorp
I bump started the flywheel without the glowplug in so it would prime the carb. When I did that, the flywheel froze. Any ideas? The flywheel should rotate counter clockwise correct?

What's wrong and how do I fix it?

Thanks.
depends WHICH END of the motor u r FACING! COUNTER-clockwise with respect to which end?

FACING the FRONT of the motor - counter-clk would be the CORRECT way to reference which direction the motor turns, i.e., as u face the front (looking at the clutch) - the motor turns counter clock-wise.

FACING the REAR on the motor - clockwise is correct. as u face the exhaust end of the motor it will rotate clock-wise.

flywheel froze?? is this a new motor? it really should be able to rotate either direction and it dosen't matter (IF ur using a BUMP start, NON-pull start motor) which way u rotate it BY HAND - u should be able to turn it over by hand easily without a plug in either direction.

now, sometimes - the conrod will come SLIGHTLY off the crank stud (not completly) and PREVENT the motor from turning over as the conrod now contacts the side/bottom of the crank case conrod well. i have seen this when i have the motor in my hands and i'm turning the motor all around while holding it - the conrod is sorta loose on the stud to allow u to remove the piston and i have noticed that it will actually come off the stud a little if u hold the motor in a certain position and rotate the flywheel.

during normal running of course this can't occur - but if ur holding the car and turning it all around - this condition COULD occur. remove the back plate and see that the conrod is not touching the crank case anywhere in it's rotation cycle.
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Old 04-13-2003, 07:15 PM   #3
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If I take the engine out and spin the flywheel by hand it won't turn over completely without forcing it.

It seems, after examining the motor with the head off that as the piston rises and reaches it's peak it lifts the sleeve as well. With the head on the sleeve isn't allowed to extend upwards and this is why the engine isn't working right...I think. Can anyone let me know what I need to do?

I've never had a NPS engine so I don't really know what may be wrong or what I should be looking at.

I can't remove the backplate. I took the 4 screws out but it won't come off. What am I doing wrong?
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Old 04-13-2003, 07:25 PM   #4
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IS this a NEW motor? even with a well broken-in motor - as u rotate the motor w/o the head - the piston will raise the sleeve slightly above the top of the case (this is how one removes the sleeve!). i dont know if u actually HAVE a prob. it sounds like it's doing what it is supposed to do. turning over a new motor there is considerable friction as the piston reaches the very top of the sleeve - it's supposed 2b that way till u break it in - after break-in the piston/sleeve frcition lessens but the piston still has a good tight fit at the very top of the sleeve.

just how much force do u need to rotate ur motor by hand? do hear any grinding - can u see any visable evidence of grinding - like metal shavings, etc.?

i dont think there is anything wrong with ur motor....

after removing the screws holding the back plate - just pull the plate straight out - it is a very tight fit - much like the way a bearing fits on a shaft - just pull steady straight out and twist slightly - it will come right out!

NOTE the orientation of the back plate as u take it out!!!!! there is usually a section cutout of the plate the prevent the conrod from hitting it - make SURE u put the plate back in the SAME way!

Last edited by cybertoolzz; 04-13-2003 at 07:33 PM.
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Old 04-13-2003, 07:32 PM   #5
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There is no grinding or metal shavings....I've been advised to heat the TDC up with a hair dryer and try to get it going that way.
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Old 04-13-2003, 07:38 PM   #6
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Quote:
Originally posted by RedScorp
heat the TDC up with a hair dryer and try to get it going that way.
u lost me there! somebody told u to move the piston to tdc THEN heat it up? if i was going to free something up that was stuck - i don't think i would put it in it's MOST binding position and THEN heat it... i would put it BDC where the friction was at it's LEAST. heat does indeed expand metal parts but that sounds suspect at best...
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Old 04-13-2003, 07:39 PM   #7
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No, I was told to heat it up where the pinch was....most likely at TDC, but not to have the piston there. My other post about rotational direction is where we've been discussing it.
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Old 04-13-2003, 07:49 PM   #8
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lol - i didnt chk that thread - i thought u were talking about a starter box wheel (easy wire switch to fix that) on that post.

look scorp - i really think ther is anything worng w/ ur motor!

u have NOT YET said if this is a NEW motor but i think it is - put some after run on that stuck piston/sleeve - then put the head back on and tighten it down. keep the plug out and just turn that puppy over using the starter or, if u have a centax clutch, a 2mm hex to turn the cap screw of the clutch COUNTER clock-wise - the piston/sleeve is SUPPOSED to be that tight!!
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Old 04-13-2003, 07:51 PM   #9
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im gonna go play COUNTER-STRIKE now...
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Old 04-13-2003, 09:10 PM   #10
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thanks for the help!
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Old 04-13-2003, 09:52 PM   #11
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btw cyber...yes it is a new motor, it seems to be better now.
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Old 04-14-2003, 05:30 PM   #12
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Quote:
Originally posted by RedScorp
btw cyber...yes it is a new motor, it seems to be better now.
ahhh - like i d=said -- u DON'T have aproob scorp! juat a new motor - fire that sucker up and runit in. the piston will get looser amd it will be perfct. i am drunk an =d cant type right... time to go run my nitro scramer at full throttle!!!
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