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Old 03-06-2009, 08:34 PM   #1
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Default Engine going crazy

To be brief my SC8 stock engine was running great prior to me taking it off chassis and cleaning. Put it back on and started it up. Was running horrible and extremly hot. Continued like this for about a quarter of a tank as I stopped the engine let it cool down check for issue and tried again. Only to have the motor scream like I had it a full throttle. Decided I had a bad air leak. So I sealed up the carb and back plate with copper permatex and tried again today after resetting all needle setting to break in. Engine ran rich of course. I then started to lean it out to try and get it back in tune. Car would not run long enough to get it to operating temps and eventually went back to the scream and not going anywhere. The only setting that I am not familiar with in the mid range screw which I was told to only have it one turn out and not touch it any more. This sucks as I a suppose to race tomorrow in a short course class. Any help is appreciated.
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Old 03-06-2009, 08:38 PM   #2
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fatten the motor up on the top to flush and turn the low end out a turn and half form where it at now.
also change all your fuel lines then do this
start the motor and lean the bottom just a lil if need to get to start then turn in the top end then do the low end to me it sounds like the low end way to lean

and also another rule the leaner the motor the lower your ideal screw need to be or how far out
the richer the motor the higer it need to be or turned in
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Old 03-06-2009, 09:48 PM   #3
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Originally Posted by porkchop View Post
fatten the motor up on the top to flush and turn the low end out a turn and half form where it at now.
also change all your fuel lines then do this
start the motor and lean the bottom just a lil if need to get to start then turn in the top end then do the low end to me it sounds like the low end way to lean

and also another rule the leaner the motor the lower your ideal screw need to be or how far out
the richer the motor the higer it need to be or turned in
sounds like might have broken tank will cause all the issues your having so check it
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Old 03-07-2009, 03:52 AM   #4
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Quote:
Originally Posted by porkchop View Post
fatten the motor up on the top to flush and turn the low end out a turn and half form where it at now.
also change all your fuel lines then do this
start the motor and lean the bottom just a lil if need to get to start then turn in the top end then do the low end to me it sounds like the low end way to lean

and also another rule the leaner the motor the lower your ideal screw need to be or how far out
the richer the motor the higer it need to be or turned in
Dude, take some short typing classes while your at it.
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Old 03-07-2009, 04:00 AM   #5
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hmm are the lines (fuel and pressure) on there correctly? might want to replace the pressure line in case the removing of it may have tore it.
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Old 03-07-2009, 05:10 AM   #6
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First thing I'd do is, remove the air filter and make sure that the carb is opperating smooth and proper. Then I'd re-set the carb to break-in settings. Leave the air filter off so you can watch the slide to be sure it's not moving from vibration or spring tention.

I'd also check the tank for good fuel flow. Put some fuel in the tank, disconnect the fuel lines, and then blow into the pressure line. You should have a good flow out of the fuel line. It would also be a good idea to be sure the pipe pressure fitting is clear.

Now try to start the engine. If it still runs at high speed it is probably from a obstruction of fuel in the carb. Time to pull out the needles, blow it out and check the o-rings.
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Old 03-07-2009, 05:15 AM   #7
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Also, when you do get it running watch for air bubbles to be passing through the fuel line to the car, if they're passing through after it has been been running for a short period of time there is a leak in the tank somewhere.
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Old 03-07-2009, 05:22 AM   #8
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Also, when you do get it running watch for air bubbles to be passing through the fuel line to the car, if they're passing through after it has been been running for a short period of time there is a leak in the tank somewhere.
Yep, I forgot mention that. Thanks.
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Old 03-07-2009, 04:52 PM   #9
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Alright, I tried everything suggested here and finally got it going. No leaks, air bubbles and fuel line is good length. By the time this occured my clutch bell screw came loose, which is another problem I have been having(another topic). Thanks for the tips and I hope to get to the track soon!
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Old 03-07-2009, 06:27 PM   #10
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LOCTITE!!! and make sure it is dry before you start your engine
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Old 03-07-2009, 07:24 PM   #11
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I thought my motor was going crazy but then I realised it was just Caster Grenade Power!!!!
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Old 03-07-2009, 07:39 PM   #12
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LOCTITE!!! and make sure it is dry before you start your engine

Huh I never thought of that. Just put new clutch bearings today and fired up right after installation. I guess if you have the time though thats a good tip. Thanks
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Old 03-07-2009, 10:34 PM   #13
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You have to Loctite your clutch nut screw and your shaft end set screw, or they will both vibrate loose...This is not a new trick..this has been a necessity since day 1
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Old 03-08-2009, 04:18 AM   #14
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You have to Loctite your clutch nut screw and your shaft end set screw, or they will both vibrate loose...This is not a new trick..this has been a necessity since day 1
I put loctite on my shaft end screw, this is the third time it has come loose. Where is the clutch nut screw? Once the clutch bell is removed everyting is just sitting there; bearings, washers and clutch shoes w/ springs.
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Old 03-08-2009, 06:14 AM   #15
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Flywheel nut???
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