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Old 03-29-2010, 02:51 PM
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Default Engine idling/starting problems

Hi all

Just wondering if you can help me with a problem I am having.

When I start my buggy on a starter box I need to open up the throttle to get it started using the throttle trim it then starts screaming its head off and when I return the trim to normal the engine dies.

Carb slider is set at about 2mm? for idle. This allows the engine to idle without stalling.

This happens obviously when cold but when engine is warmed up (eventually after much frustration on getting it going) it still does the same thing except not as bad. I thought I had the thing tuned but obviously not.

Car stalls alot and is getting the better of me as I want to start racing and cant have this happening on the track. I live a fair distance away from the nearest race club so getting help is a problem too.

I have read various engine tuning posts but it still seems to be not too clear to me on if there is a tuning problem or what?!

Your thoughts, comments and help please and appreciated.

Nitrolizard
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Old 03-31-2010, 12:06 PM
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I am learning tuning myself and here is what I learned. When you have it all goofed up, then go back to the factory settings and start again. The manual will tell you settings for your low and high speed needles as well as the air gap for idle. That will give you a safe place to start.
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Old 03-31-2010, 02:32 PM
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Originally Posted by nitrolizard
Hi all

Just wondering if you can help me with a problem I am having.

When I start my buggy on a starter box I need to open up the throttle to get it started using the throttle trim it then starts screaming its head off and when I return the trim to normal the engine dies.

Carb slider is set at about 2mm? for idle. This allows the engine to idle without stalling.

This happens obviously when cold but when engine is warmed up (eventually after much frustration on getting it going) it still does the same thing except not as bad. I thought I had the thing tuned but obviously not.

Car stalls alot and is getting the better of me as I want to start racing and cant have this happening on the track. I live a fair distance away from the nearest race club so getting help is a problem too.

I have read various engine tuning posts but it still seems to be not too clear to me on if there is a tuning problem or what?!

Your thoughts, comments and help please and appreciated.

Nitrolizard
1. what type of motor
2. what type car
3.how much have you turned ont he low speed and high speed needles
4. 2mm gap on the idle is way to much

answer these questions and lets see if we can help
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Old 03-31-2010, 07:55 PM
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Thanks for the reply guys.

Motor is Hyper .21 8 port car is Hyper 7 PBS.

Will go back to factory settings and see how it goes.

Cheers

Nitrolizard
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Old 03-31-2010, 08:14 PM
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Originally Posted by nitrolizard
Thanks for the reply guys.

Motor is Hyper .21 8 port car is Hyper 7 PBS.

Will go back to factory settings and see how it goes.

Cheers

Nitrolizard
ok let us know how it goes from there ...
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Old 03-31-2010, 09:59 PM
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If your idle gap is 2mm, then your low speed needle must be set very rich.
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Old 04-01-2010, 07:21 AM
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try change the glow plug
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Old 04-09-2010, 12:38 PM
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Thanks for all the input guys.

Engine is now running sweet after going back to stock settings and retuning. Also changed glow plug and ajusted idle back to stock setting.

Idle is now a little high so does it need more fine tuning?

Also when accelerating from a standing start with full throttle engine tends to be slow for a couple of seconds then accelerates nicely. Is this too rich or too lean on LSN?

Thanks

Nitrolizard
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Old 04-09-2010, 07:16 PM
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Originally Posted by nitrolizard
Thanks for all the input guys.

Engine is now running sweet after going back to stock settings and retuning. Also changed glow plug and ajusted idle back to stock setting.

Idle is now a little high so does it need more fine tuning?

Also when accelerating from a standing start with full throttle engine tends to be slow for a couple of seconds then accelerates nicely. Is this too rich or too lean on LSN?

Thanks

Nitrolizard
When it's "slow for a couple seconds", is it blowing lots of smoke, or no smoke?
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Old 04-09-2010, 07:59 PM
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Originally Posted by nitrolizard
Thanks for all the input guys.

Engine is now running sweet after going back to stock settings and retuning. Also changed glow plug and ajusted idle back to stock setting.

Idle is now a little high so does it need more fine tuning?

Also when accelerating from a standing start with full throttle engine tends to be slow for a couple of seconds then accelerates nicely. Is this too rich or too lean on LSN?

Thanks

Nitrolizard
I would be willing to bet you are a bit rich on the top end.

To check your bottom end, pinch the fuel line while it is idling and see how long it takes for the motor idle to change. should be around 3 seconds. if it is more then the bottom is fat if it is less than two seconds then the bottom is lean. Get that set right then go to the top end and adjust for your punch. you can fine tune from there.
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Old 04-09-2010, 10:27 PM
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Just my .02! I had and still have sometimes similar trouble. One thing I found is that sometimes no smoke can be from being too cold(too fat) I kept richening trying to get smoke but had no luck. I leaned it down just some trying to get my temp to around 200 then I started to get smoke and could make small tuning adjustments accordingly. I also highly recommend pre warming your engine, I fought tuning issues for a long time just from making adj when cool then changing as the engine warmed. Good luck and I fully understand your frustration with learning the tune. P.S. Check for air leaks too. Most of my engines have had leaks around the screw that holds the carb in, fixed those air leaks and idle was MUCH better.
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