drop down test

The Force power

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Compression reading results;
#1 @ 134 / #2 @ 136 / #3 @ 140 these reading are taken with a different gauge the previous results posted.
Ignition test = good firing at all Cylinders & a good spark jump

Still no drop in RPM's when #1 gets unplugged, so then it can only be fuel related? pump pressure?

Sprayed a quick squirt of brake-cleaner into #1 carb. and it surged!
(DISCLAIMER; this is NOT a good practice & not recommended, just to clarify for the folks that don't know this)

This would indicate to me a fuel-issue, so I adjusted the fuel/air mixture screw to 1&1/2 turn out(from 1&1/8) revved the engine a couple of times to get adjusted.

Would you believe?!? it made it run on the top Cylinder meaning; the RPM's drops down now when I unplug #1

Someone's theory & explanation is greatly valued
 

GA_Boater

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The top carb needed adjusted. Probably the others also need tweaking.

The screw you adjusted is for idle mixture.
 

The Force power

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lol I'm aware of the Idle mixture screw, you think the float on the top carb. is not working right?

I'll have to clean it again,I bought a pressure gauge for the fuel-pump. so at full cranking speed check the out put pressure?
 

jerryjerry05

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May 7, 2008
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If the pressure gauge works when you try.
It might show 2-3# of pressure.

It's possible the needle/seat is stuck, not letting fuel through.

The needle, does it have a rubber tip or solid tip?
The solid needle/seat has a tiny o-ring in the bottom.
The fuel additives//cleaners can make the o-ring swell and shut off the fuel.

Set the float level? and drop?

What rpm's you getting at wide open?
 

The Force power

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good morning Jerry,
Thanks for tuning in, the needle has a solid tip / the float level is bang-on & the drop is enough for the needle to let fuel by.
(Pressure checked by mouth)

the motor hanging a test-tank, so I can't check rpm's wide open
 

jerryjerry05

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May 7, 2008
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16,481
You have spark checkers?

Since it's the top carb, you can reach the screw holding the bowl.
Undo it and squeeze the ball and see if gas comes out.

Primer or choke?
Primer can be feeding excessive amounts of gas.
After starting, pinch off the feed from the primer.

Inspect the reeds?
 

The Force power

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Good idea! I'll check the top carb. that way
-good spark, jumps 1/2'
-choke
-reeds are mint
thank you Sir
 
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