PRIMER bulb "PRIMING"

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Re: PRIMER bulb "PRIMING"

The other thing that will keep a bulb from pumping up hard is a leak between the bulb and the fuel tank.
It will not leak gas out, it will draw air into the system and will be extremely difficult to prime and most probably cause the engine to starve for fuel when you try to give it more throttle.
This usualy happens with worn fittings on portable fuel tanks.

you can also have air leaks upstream of the bulb, especially the fitting at the motor, so it may be better to rig it with a direct connect. test with soapy water.
 

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Re: PRIMER bulb "PRIMING"

I have a Yam 50 that does not have a key choke; it's all "automatic". It is also unlike any motor I have ever seen, where you do NOT lift the warm up lever until after the motor starts. It's a boat I share with 6 other families, and I know many of the other operators don't know this. You can still push the key in and so they all think it's choking the motor.
 

brnschoneck

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Feb 22, 2013
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Re: PRIMER bulb "PRIMING"

What it supposed to happen.....

Pumping the primer bulb pumps fuel from the tank, through the fuel pump and into the carburetor bowl.
Once the Carb bowl is full, the float shuts the float valve and no more fuel comes in.
The bulb should get hard because there is nowhere to pump the fuel.
If it keeps pumping and floods the engine, the float(s) is/are stuck or a float valve is bad.
Once the engine starts, the float and float valve need to be working or the fuel pump is going to make the engine run very rich, if at all.
The primer bulb is just a manual fuel pump for use before the engine starts.

Pushing in the key, if you have this feature, operated the CHOKE.
It is not a remote primer.
Pushing it in and out 5 times does nothing but operate the choke 5 times.
Push it in and hold it while turning the key.

I have a black button to puch for choke so ....
 

brnschoneck

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Feb 22, 2013
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Re: PRIMER bulb "PRIMING"

100% true... I had a '70 Merc 800, I would squeeze till I heard fuel squirting in the carbs, and then squeeze a few more times. It couldn't be flooded.

thats what i do seems to be working fine ...
 

brnschoneck

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Feb 22, 2013
Messages
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Re: PRIMER bulb "PRIMING"

100% true... I had a '70 Merc 800, I would squeeze till I heard fuel squirting in the carbs, and then squeeze a few more times. It couldn't be flooded.

thats what i do , i do have electric choke and manual if needed the electric is a little black push button ??? im thinking someone may of added it where the rpm cable is supposed to go in according to the manual ????
 

Part-time

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Re: PRIMER bulb "PRIMING"

you can also have air leaks upstream of the bulb, especially the fitting at the motor, so it may be better to rig it with a direct connect. test with soapy water.

A leak up from the bulb would have gas coming out when you sqweez the bulb.... but it would draw air when the motor is running.
 
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