Tuning Help Part 2. My FH likes to run Rich.

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Small2Large

Small2Large

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So I couldn't get my FH to run at full throttle, but it would fine at half throttle. I started at the base 1.5 turns H and 1.25 turns L. The more I leaned, the worse it got. So I gave running richer a try. Ended up around 1.75 turns H and 1.5 turns L and it actually ran damn good. Problem now is I can't get the buggy to idle with the Low set so high. I have to turn the throttle trim up past where the idle screw can even be set. When I hit the brakes, it closes the carb to much and kills the engine.

What should I do now?
 
Do you have the big silver adjustment screw turned in enough to keep the carb open?

If you do, then lean the Ls needle a little to keep the rpm's up enough to keep the motor running.

The easiest way to do this that I know of is to... Have a buddy hit full throttle and you adjust the HS until the motor peaks out then back it out 1/16 turn.

Let the motor return to idle and lean the LS until the motor peaks in rpm, then back it out 1/16 and adjust the silver screw to get the idle speed you are looking for. That's it!

I just did this to Meli's Mutilator (Same car as yours) and it worked great.
 
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Trip said:
Do you have the big silver adjustment screw turned in enough to keep the carb open?

If you do, then lean the Ls needle a little to keep the rpm's up enough to keep the motor running.

The easiest way to do this that I know of is to... Have a buddy hit full throttle and you adjust the HS until the motor peaks out then back it out 1/16 turn.

Let the motor return to idle and lean the LS until the motor peaks in rpm, then back it out 1/16 and adjust the silver screw to get the idle speed you are looking for. That's it!

I just did this to Meli's Mutilator (Same car as yours) and it worked great.
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I've got the big silver screw all the way in and it will still die at idle. The carb needs to be open more than the silver screw can adjust to in order to keep the engine running.

I've already tried what you mentioned and the engine runs get at high rpm as it is right now. It just can't idle.
 
If you lean the LS needle, it will raise the idle RPM, similar to what the silver screw does.

Or how about this? What does the motor DO if you turn in the LS needle?
 
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Trip said:
If you lean the LS needle, it will raise the idle RPM, similar to what the silver screw does.

Or how about this? What does the motor DO if you turn in the LS needle?
Click to expand...

That's when it wants to die at full throttle. It will idle perfect, but bog/die at full throttle. Half throttle will be fine, but of course the top speed is lacking.

I've tried opening up HS needle while turning in the LS needle and it just wants to die even faster at full throttle.
 
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Are you sure you are adjusting the correct needle? The LS needle is the one closest to the motor and the HS is closest to the air filter.

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NewCamera223.webp

Adjusting the LS needle should have little, to no affect on the top end speed.
 
Trip said:
Are you sure you are adjusting the correct needle? The LS needle is the one closest to the motor and the HS is closest to the air filter.

NewCamera222.webp
NewCamera223.webp

Adjusting the LS needle should have little, to no affect on the top end speed.
Click to expand...

I'm absolutely positive. I'm going to take the carb off and clean it up real good and change the plug also.
 
Before you pull the carb, check to see if the carb screws are tight... After thinking about what Super posted, it may be an air leak... I think I was thinking backward again... Damn Flu has me all messed up!

I'm goin to bed!!!
 
Trip said:
Before you pull the carb, check to see if the carb screws are tight... After thinking about what Super posted, it may be an air leak... I think I was thinking backward again... Damn Flu has me all messed up!

I'm goin to bed!!!
Click to expand...

Air leak where? Where the carb meets the engine?
 
Checked the screws, gasket, air filter, and tubes, even put in a new spark plug. It still wants to run rich in order to go full throttle without bogging/dying.
 
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