Stalling and Starting problems

alldodge

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Will dig them up later and post if someone else doesn't

The top of the carb comes off to adjust. Upside down for float level and right side up for float drop
 

alldodge

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Here ya go. This first pic is where to adjust float level when upside down. The float drop bends float arm. Be careful bending
Carb float Adjust.jpg

Slide1.JPGSlide2.JPGSlide3.JPG
 

zellerj

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Dec 13, 2017
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Sometimes a floating piece of dirt (or piece of rubber from a hose downstream from the filter) can block the jet and cause a stall. Draining the float bowl and looking for black specs might give you a clue.
 

Scott06

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Took the filter off and gas was clean, but there was a little dirt at the bottom of the jar I poured it into. Started the engine, goosed it until it died, and looked into the carburetor and saw a puddle of gas. What causes this?
As AD stated Check your float level as shown.

Also would check there is no debris in the needle and seat and the float is not gas soaked
 

amplay

Seaman
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Sep 29, 2022
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Thanks for all your help guys. I got in to check the float adjustments. The Float Level is supposed to be 10mm, and mine was about 11, so I made a small change. The Float Drop is supposed to be 24mm, and mine was about 40. I guess the guy who rebuilt the Carb was careless. Made that change and it ran great all day today. I'm optimistic that the issue is resolved.
 

Jmunk

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Looking at your carburetor the finish and screws makes me think it could be an aftermarket unit and not OEM.
 

amplay

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I have not been to my boat in over a week, but went today. It kept flooding on idle. It even was pouring gas into the carb with the engine, and key, off. Any ideas?
 

Scott06

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I have not been to my boat in over a week, but went today. It kept flooding on idle. It even was pouring gas into the carb with the engine, and key, off. Any ideas?
Measure your fuel pressure should be no more than 6 psi. Make sure no power is getting to fuel pump when engine is off.
 

Scott06

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How would I measure the fuel pressure
With a fuel pressure gauge stabbed into the fuel line. im sure you can find some you tube videos of it.

merc makes a fitting to put between fuel line and carb but its kind of expensive fitting. You can probably scab something together with 3/8 flare fittings and a t
 

amplay

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With a fuel pressure gauge stabbed into the fuel line. im sure you can find some you tube videos of it.

merc makes a fitting to put between fuel line and carb but its kind of expensive fitting. You can probably scab something together with 3/8 flare fittings and a t
Thanks, I'll do that. What makes the fuel pump run or not run. I think it was running with the key off
 

nola mike

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Pump shouldn't be running with the key off. Double check that. When you had the carb off, did you check the needle and seat? You need to make sure the needle is sealing
 

amplay

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The Service Manual says :
If your engine floods at idle rpm, check the following:
1. Problem in ignition system causing engine to run rough.
2. Idle mixture screw adjusted incorrectly.
3. Bad needle and seat.
4. Incorrect float level or drop.

How can the idle mixture screw cause this issue, and how should I adjust if it is?
 

nola mike

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The Service Manual says :
If your engine floods at idle rpm, check the following:
1. Problem in ignition system causing engine to run rough.
2. Idle mixture screw adjusted incorrectly.
3. Bad needle and seat.
4. Incorrect float level or drop.

How can the idle mixture screw cause this issue, and how should I adjust if it is?
1. Not #1
2. Not #2
3. Mentioned at least twice so far in this thread
4. You said you already checked and adjusted
 

Scott06

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Thanks, I'll do that. What makes the fuel pump run or not run. I think it was running with the key off
If it is running with the key off there is a problem and someone may have futzed with the factory wiring. The pump gets power i think off the starter during cranking , then off the ignition circuit via an oil pressure switch during running.
oil pressure switch is there to prevent pump from running when the ignition is on and engine is not running.
 

amplay

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Sep 29, 2022
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I've changed the needle valve and seat, and flooding continues. As suggested, I want to test the fuel pump pressure. Attached is my pump, fuel line, and pressure gage. I've searched online, and cannot find an adapted. Any suggestions?
 

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