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Old 06-10-2003, 09:02 PM   #16
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I just checked the bearing, carb seal, and all of the o-rings; everything is perfect with good seals. I also inspected the fuel line and they were also in perfect condition, however I just replaced it to be safe.

I also took apart the motor, it was in mint condition aside from a little bit of brownish orange residue on top of the piston.

Not sure if this means anything, but i'm using an aluminum Du-Bro fuel filter. The filter was clean and there was nothing blocking the fuels route, however i'm not sure if the filter could be causing the problem or not. When I just put the new fuel line on, I didn't put on the fuel filter. Also, i'm using a #5 NovaMega glowplug and I live in extremely hot and humid Florida.

Just to clarify, when the engine is first started up the idle is perfectly normal, the idle doesn't go crazy until 3-4 minutes of driving the car, but in those 4 minutes the idle is perfect and all of a sudden goes crazy out of nowhere.

Last edited by Accord; 06-10-2003 at 09:10 PM.
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Old 06-10-2003, 09:14 PM   #17
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You dont need a fuel filter....the tank has one already!!
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Old 06-10-2003, 10:18 PM   #18
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I think I have found your problem.

Your tank.

The foam seal in the head of the tank have been known to cause problems. They get saturated with fuel and then they dont keep the lid airtight which would explain why you are going lean and having idle problems after a few minutes running.
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Old 06-11-2003, 09:05 AM   #19
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Default Sorry to interupt

What kind of of sx12 is it?


M.S. or not M.S. ?

turbo, or non turbo?


What is the temp of the motor?

Is it Choking or Bogging before it dies?

I really recommend a temp gun if that same problem keeps existing and still having unbalanced needle setting.

Last edited by it; 06-11-2003 at 09:24 AM.
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Old 06-11-2003, 09:30 AM   #20
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Quote:
Originally posted by PUNISHER
Modellor,
I believe that Accord's motor and car is new so he shouldn't have any problems with a bad front bearing, o-rings or holes in the fuel line. HOWEVER, that is still a good idea to check them.


Accord,
Make sure that all the screws on the motor are tight and there!!
Nizee gave you a good hint to check your carb seal to the motor....make sure its all the way in and on tight. Nizee and modellor are correct about not having a compression problem it a air-leak problem and lean setting.
.


Just a small advice. Not too tight on the screws when you put your heatsink back.

There are Torque specs on the heatsink on how much you can turn. Make sure you do not go all the way down to a level that you cannot move the screws anymore.

Tightening the screw too much will create different pressure on the combusttion chamber. It will be unbalance on one side of the motor.

Just screw in slow and when you reach the end give about 30 to 50 degree clockwise w/ tightening the screw crosswise.

Hope this helps!!
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Old 06-11-2003, 10:49 AM   #21
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Default Re: Sorry to interupt

Quote:
Originally posted by it
What kind of of sx12 is it?


M.S. or not M.S. ?

turbo, or non turbo?


What is the temp of the motor?

Is it Choking or Bogging before it dies?

I really recommend a temp gun if that same problem keeps existing and still having unbalanced needle setting.
It is not an MS and it is not Turbo. I'm not sure what the temperature is, but when I put drops of water on the head it evaporates after about 3 seconds. It does not choke or bog before it dies... the idle just goes very high and it will die.
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Old 06-11-2003, 10:59 AM   #22
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Quote:
Originally posted by Accord
It is not an MS and it is not Turbo. I'm not sure what the temperature is, but when I put drops of water on the head it evaporates after about 3 seconds. It does not choke or bog before it dies... the idle just goes very high and it will die.
Not to offend you, drops of water can be a really hard hint to determine the temp.

Hopefully, your shop or one of your fellow racer can let you borrow a temp gun.

I had the same problem of a Novamega sx12 3 port Re that came in with impulse streetspec (the first impulse).

It was one of the harderst and hottest motor I have encountered.

If you can start your motor and can get a temp for me after it dies. My setting would be a solution to your problem.

Note: I am not 100% sure it will work, but it might just be the solution to your problem.

Honestly, its hard to tune a motor If you cannot hear, see, or feel. However, I will be willing to give it a shot and hopefully work so you can get the performance you need.
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Old 06-11-2003, 12:02 PM   #23
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Default Re: SX12 Problems

Quote:
Originally posted by Accord
I am having so many problems with my SX12 engine, I am getting EXTREMELY frustrated, I feel like throwing the damn engine through a window!

I'm breaking in the engine, i'm on my 6th tank. It will just randomly start when I try mabye one out of ten times, the car will run beautifully for about 3 minutes, then the engine will begin to idle extremely high even with the carb slide completely closed, mind you the engine does not shut off, it just idles extremely high regardless of my idle and low end needle settings. Of course I shut the engine off and check everything, and when I go to restart it the the engine just won't start nomatter what I do, however it eventually starts after like 30 minutes of trying everything, and I didn't even do anything special; it's like the damn engine has a mind of it's own and is out to get me! The engine will not start, I have tried numerous glowplugs and they are all fine, I have tried using different glow igniters, I have tried the pressure lock thing where you cover the exhaust pipe for 2 seconds and dry-start it like it says in the manual, I have tried every possible setting on the needles, and to no avail, THE ENGINE WILL NOT START! AHHHHHHHHHHHHH! This time the engine won't start at all, also the 12v powersource for my powerstart box is fine. I am running 30% nitro fuel, this is what my LHS reccomended.

This problem only started happening on the 5th tank or so throughout the break-in, before that it started up instantly and I never had any problem at all.

I've tried everything I can think of, nothing works.

can I sugest something? Can you check if it is possible, right after the engine dies-if there is everything turning or moving absolutly free, if there is nothing feel lose. It might be after running 3 minuts something goes bad due to the temperature expancion too. And after your engine dies it needs time to get all parts to its original position. yuo can check this possabilities too.
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Old 06-12-2003, 12:36 AM   #24
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I have a question about my SX12...It starts and runs great, but when I come in for a pitstop, invariably, as I try to leave it dies. It fires right back up after, no matter how hot... It blows smoke under acceleration, and even though I have the idle set fast it dies at the end of the pitstop.
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Old 06-13-2003, 03:42 PM   #25
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Okay guys, well apparently the problem was infact a messed up front bearing. I bought a new front bearing, and I talked to Serpent USA and they told me I have to heat the engine up in a toaster over or something and then pop it out, but in the process the main bearing would be damaged and I would have to replace that .

Also, I am having an impossible time trying to get the Flywheel off, so does anyone have any tips on getting it off?

How can I easily change out the front bearing without damaging anything?

Last edited by Accord; 06-13-2003 at 03:57 PM.
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Old 06-13-2003, 04:19 PM   #26
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An OFNA bearing puller #10797.....


A nice tool to have but a better tool to have is a temperature gun!
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Old 06-13-2003, 04:24 PM   #27
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I just got the flywheel off with a flathead screw driver, so now i've got to remove the piston. I tried sliding the piston rod off the crank, but it is held on by mabye .3mm and I can't force it off anymore. Any other tips for getting pistons off?

Last edited by Accord; 06-13-2003 at 05:00 PM.
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Old 06-13-2003, 05:04 PM   #28
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Quote:
Originally posted by PUNISHER
An OFNA bearing puller #10797.....


A nice tool to have but a better tool to have is a temperature gun!
yes this bearing puller is very good i use one myself and find it fantastic!

jeremy
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