I have a 1990 mercury 175hp magnum II RX4 outboard with the WalBro WHM carburetors on the motor. My carbs are the single float carbs that have the accelerator pump off to the side. Of the carb
Serial number OC289990
Side note:: According to the Seacor Manual the WMH Walbro carbs with the accelerator on the side which I have on my 1990 motor)(these special carbs only came on 1991 Mercury motors, so says the SeaCor manual.) there on my 1990
my problem is that I can't get the primer bulb to fill up, and it gets soft while running, which is ok while the engine is running, but the motor will run smooth as a kittens purr only if, I give it enough throttle in neutral, or in D or R it runs fine with some throttle. But engine stops running with no throttle
when I put the engine in neutral, it keeps on running until it burns the existing gas off and then the engine dies out. ((( Once the engine cuts off, ))) I can pump & pump the primer Bulb until the cows come home & I can't get the primer bulb to pump up for nothing. I have replaced all new mercury fuel lines from the carburetors back to the fuel separator
i have 3 new primer bulbs, which, if I remove the fuel line at the exit side of the fuel water seperator or (( right after the Fuel water separator . to be clear, )) I can drop the fuel line in a portable gas tank & the bulb gets nice and hard in just 2 pumps of my hand. And the Motor will run smooth for as long as I have the fuel line in that 2 secondary gas tank, I can turn the key, crank the motor, let it run in any gear at any throttle position perfectly.
one thing I have discovered is this:
because I can hear air coming from the bottom Carburetor making a Swooshing Sound when I pump the primer Bulb & the bulb won't pump up. I took the fuel line off that is going into the bottom carb. I blew into the fuel line & i can see that the seater valve that the fuel bowl float opens and closes allows air to freely flow when I blow into the fuel line. Once I lift the float a little it closes the air flow off and so I adjusted the silver tab on the fuel float to try and get that seater valve to close.
My thought is that if that is closed then the primer bulb will pump up and my problem will be fixed.
NO LUCK. Seems like the sound now is coming from the middle carb maybe. But it's not coming from the bottom carb, and the bulb still won't pump up.
And all of that may not have anything to do with why my primer bulb won't prime up.
I have put new fuel lines, from carbs back to separator, siphon valve, fuel water separator and mount,
Fuel tank built in under the deck.
Anyone got any ideas on this one.
Serial number OC289990
Side note:: According to the Seacor Manual the WMH Walbro carbs with the accelerator on the side which I have on my 1990 motor)(these special carbs only came on 1991 Mercury motors, so says the SeaCor manual.) there on my 1990
my problem is that I can't get the primer bulb to fill up, and it gets soft while running, which is ok while the engine is running, but the motor will run smooth as a kittens purr only if, I give it enough throttle in neutral, or in D or R it runs fine with some throttle. But engine stops running with no throttle
when I put the engine in neutral, it keeps on running until it burns the existing gas off and then the engine dies out. ((( Once the engine cuts off, ))) I can pump & pump the primer Bulb until the cows come home & I can't get the primer bulb to pump up for nothing. I have replaced all new mercury fuel lines from the carburetors back to the fuel separator
i have 3 new primer bulbs, which, if I remove the fuel line at the exit side of the fuel water seperator or (( right after the Fuel water separator . to be clear, )) I can drop the fuel line in a portable gas tank & the bulb gets nice and hard in just 2 pumps of my hand. And the Motor will run smooth for as long as I have the fuel line in that 2 secondary gas tank, I can turn the key, crank the motor, let it run in any gear at any throttle position perfectly.
one thing I have discovered is this:
because I can hear air coming from the bottom Carburetor making a Swooshing Sound when I pump the primer Bulb & the bulb won't pump up. I took the fuel line off that is going into the bottom carb. I blew into the fuel line & i can see that the seater valve that the fuel bowl float opens and closes allows air to freely flow when I blow into the fuel line. Once I lift the float a little it closes the air flow off and so I adjusted the silver tab on the fuel float to try and get that seater valve to close.
My thought is that if that is closed then the primer bulb will pump up and my problem will be fixed.
NO LUCK. Seems like the sound now is coming from the middle carb maybe. But it's not coming from the bottom carb, and the bulb still won't pump up.
And all of that may not have anything to do with why my primer bulb won't prime up.
I have put new fuel lines, from carbs back to separator, siphon valve, fuel water separator and mount,
Fuel tank built in under the deck.
Anyone got any ideas on this one.
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