noobie carb question

bpmcl00

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My carb has some issue not getting gas when i pump it to start. once it starts its fine for the day...

instead of using started fluid to get the motor turning, could i just pore gas down into the carb?


any one see an issue with this. my motor is 1994 4.3 lx with 4 barrel.

i plan on rebuilding the carb soon but until i do i would like to find a way around using the started fluid which i know is not good to use
 

JustJason

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Re: noobie carb question

Do you prime the motor by putting the throttle in neutral and pumping it twice then hold it 1/3 open before starting?
 

bpmcl00

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Re: noobie carb question

Do you prime the motor by putting the throttle in neutral and pumping it twice then hold it 1/3 open before starting?

yes. that still doesnt work.

will it be okay to pour gas directly down the carb?
 

JustJason

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Re: noobie carb question

It won't hurt... but i recomend you fix your problem.
 

chiefalen

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Re: noobie carb question

You don't need alot about a ounce or 2 down the carb.
 

JustJason

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Re: noobie carb question

well... pull the flame arrestor off of the carb, open the choke by hand, have a buddy put the throttle in nuetral and give it a couple of pumps. Do you see 2 streams of fuel spraying down the bore of the carb?
 

Maclin

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Re: noobie carb question

I am going to assume a little bit here and say your system probably has an electric fuel pump.

The electric fuel pump will only get power while cranking, and then only gets power once the engine is running. This is due to a safety feature that includes an oil pressure safety switch. Sometimes the carb drains down some and the accelerator pump in the carb does not squirt into the throat well until more gas is in the carb. Some rig a momentary push putton or other spring loaded switch across the oil pressure safety switch. Then when the key is ON they push the button or lever and get power to the fuel pump for a few seconds to fill the carb before starting. Then pump the throttle and turn the key to START, that usually works well.

The key to remaining safe while rigged this way is a MOMENTARY spring loaded push button or lever switch, that way it can only give power to the pump with operator action.
 

bpmcl00

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Re: noobie carb question

interesting read maclin..

you are right about the electric fuel pump.

i will have to look into making this button you speak of
 

Surfdancer

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Feb 19, 2008
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Re: noobie carb question

Had the exact same problem on my Mercruiser 888, with the 2bbl Rochester carb. The accelerator pump wouldn't pump.

The aluminum check ball under the plunger spring was stuck and wasn't working right. No fuel was being drawn into the plunger bore.
 
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Re: noobie carb question

I had the same problem with my 4.3. I installed a momentary switch on the dash and replaced the antisiphon valve at the tank. Been fine ever since.
 

bpmcl00

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Re: noobie carb question

I had the same problem with my 4.3. I installed a momentary switch on the dash and replaced the antisiphon valve at the tank. Been fine ever since.

Could any of you guys be so kind as so post some schematics of this wiring. im still having a little trouble figuring this out....

Thanks a bunch
 

JustJason

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Re: noobie carb question

Instead of doing that. Why don't you fix the leaking carb plug wells with some epoxy. That's your problem.


Could any of you guys be so kind as so post some schematics of this wiring. im still having a little trouble figuring this out....

Thanks a bunch
 

bpmcl00

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Re: noobie carb question

How do i do that?

im sure you have better things to do then give me step by step instructions. but can you give me a brief description.

Thanks
 

180shabah

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Mar 26, 2005
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Re: noobie carb question

This is a weber 4bbl right?

They have a "known issue" - fuel bowl drains when engine not running.
Do a search on here for weber and focus on the posts by achris.

Short, short version, install the switch. Prime the fuel system then it will start very easily.

At the top of this forum is the "Adults Only" sticky - the Factory manual for you engine is available for download - it contains all the wiring schematics you need.
 
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