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Old 01-28-2009, 01:55 PM   #1
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Default Ofna/Hyper 21 rebuild

Hi, I think I just damage my hyper 8.5 engine on my 5 tank,
maybe it was to lean, the car just stop, and the engine is very
hard to turn around TDC with no plug.

Anyway how can I tell it if the engine is damaged, and how to
take the conneting rod off the crankshaft, if at BDC there is a
grove, and at TDC there seens no room to do-it.


Luis
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Old 01-28-2009, 02:41 PM   #2
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Quote:
Originally Posted by mpluis View Post
Hi, I think I just damage my hyper 8.5 engine on my 5 tank,
maybe it was to lean, the car just stop, and the engine is very
hard to turn around TDC with no plug.

Anyway how can I tell it if the engine is damaged, and how to
take the conneting rod off the crankshaft, if at BDC there is a
grove, and at TDC there seens no room to do-it.


Luis
once you pull out the sleeve and you should be able to take the engine apart.
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Old 01-28-2009, 03:03 PM   #3
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I have already pull out the sleeve out, but the piston is still connected
to the crankshaft via conneting rod, to take the rod from the crank is the
problem because at BDC there is a grove and at TDC the is no room to
pull it of the crankshaft.
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Old 01-28-2009, 03:08 PM   #4
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Quote:
Originally Posted by mpluis View Post
I have already pull out the sleeve out, but the piston is still connected
to the crankshaft via conneting rod, to take the rod from the crank is the
problem because at BDC there is a grove and at TDC the is no room to
pull it of the crankshaft.
did you take the back plate or pullstart? should be able to get it out with no problem..maybe i didnt understand the question
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Old 01-28-2009, 03:24 PM   #5
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Back plate is out, here is a pic, you can see the grove that does not
allow to pull the rod out the crankshaft, this is my first nitro engine

Maybe I have to take the crank from the front of the engine
Attached Thumbnails
Ofna/Hyper 21 rebuild-015.jpg  
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Old 01-28-2009, 03:44 PM   #6
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more pics
Attached Thumbnails
Ofna/Hyper 21 rebuild-013.jpg   Ofna/Hyper 21 rebuild-016.jpg  
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Old 01-28-2009, 03:55 PM   #7
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move the piston up and you should be able to move around the piston until the conrod comes off the crankshaft..
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Old 01-28-2009, 03:55 PM   #8
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Just because the car stops or died, doesn’t meant that you damaged anything. Did you lean it out? Factory settings are always really rich and that some time causes new motors to stall.

As for taking the piston out, the piston should move around inside the block now that the sleeve is out. Use a pair of needle nose pliers and grip the rod and it should EASLY slide right of the crank. As your pulling on the rod, you can rotate the crank and see what give you the best angle to get the rod off.
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Old 01-28-2009, 04:33 PM   #9
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Madbrad /D8, At TDC there is no room for the conrod to move fully
so it does not work, and at BDC there is still the groove.

The engine did go out at WOT at there was little or no
smoke from the pipe maybe I did pushed too hard.
here is a pic from the top of the sleeve, it as a ring color and
is here TDC that the piston is hard to turn.
Attached Thumbnails
Ofna/Hyper 21 rebuild-01.jpg   Ofna/Hyper 21 rebuild-02.jpg  
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Old 01-28-2009, 06:13 PM   #10
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i know that you are about to go crazy but it should come.. hold the engine over your head and look at the conrod as you are turning the shaft then find the best angle for the conrod to come out..

Last edited by D8; 01-28-2009 at 06:28 PM.
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Old 01-28-2009, 06:17 PM   #11
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Your crankshaft has moved back a tad. Push the crankshaft forward, then there will be clearance to remove the connecting rod. Push the whole thing forward in the engine, or pull from the front. It is not seated properly in your case
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Old 01-29-2009, 12:11 PM   #12
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I just found out that the suden stop at WAT of the engine was a burnt
plug not engine seizure, the OS #8 plug just "exploded" and there were
debries inside the engine I just look at the plug today and found
out, anyway I rebuild the engine and it fire up nice, but the engine as
a tight fit just because it is new (this is my first nitro). Thanks all for the support
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Old 01-29-2009, 12:23 PM   #13
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Quote:
Originally Posted by mpluis View Post
I just found out that the suden stop at WAT of the engine was a burnt
plug not engine seizure, the OS #8 plug just "exploded" and there were
debries inside the engine I just look at the plug today and found
out, anyway I rebuild the engine and it fire up nice, but the engine as
a tight fit just because it is new (this is my first nitro). Thanks all for the support

glad you got it running again. But i would run it rich for a few more tanks..JMO
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Old 01-29-2009, 12:34 PM   #14
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You bet layedbackguy, from now on I will be extra carefull and maybe
buy a temp gun an try maitain a level temperature, i was bashing on a long
straight, pushing this new baby to much Fun but almost fried it up
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Old 01-29-2009, 12:40 PM   #15
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I had a hyper motor years ago, and it last a nice while before i got dirt in it.. Nice strong cheap motor for a newbie to nitro.

Good luck my friend
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