4.3 L Mercruiser not getting fuel

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raging_gumby

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I have a 92 Bayliner capri with a 4.3 liter mercruiser in it. It turns over just fine and if I spray engine starter in the carb it fires up great. It has to be a fuel issue. I changed the fuel pump and it still is not getting fuel. Is there a fuel pump fuse? If so where is it located? Can anybody think of something else that could be causing this? Thanks!
 
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spktho

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Re: 4.3 L Mercruiser not getting fuel

If it's an electric fuel pump you need to check a couple of places. When first cranking the engine the fuel pump gets voltage from the selenoid/starter. Trace the wire(s) from the pump to the starter and make sure there is volatge from the starter.

After the engine starts, the voltage to the fuel pump goes through the oil pressure switch in mercs.

If yours is cranking, but not getting fuel, then you need to check the wire(s) from the starter.
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

Thanks. Its getting power when it cranks but the fuel never makes it to the engine to start. I dont know what could be the problem. Shouldnt the fuel pump have power as soon as the key is turned on? I am at a complete loss as to what could be causing this? Any help or insight would be great.
 
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ctak

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Re: 4.3 L Mercruiser not getting fuel

I had a similar problem with my 4.3LX it has an electric fuel pump. My problem was a bad safety switch by shift lever. If it isn't making contact then the engine won't start or get fuel. Also there is a oil pressure sensor on the motor underside. This needs to sense oil pressure or the fuel pump won't work. You can test the safety switch w/ a ohm meter and check the oil sender to make sure it's working. If you hook up 12 v to the pump does it run, you can hear the pump clicking when it's running.
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

Ok I checked the switch its not bad and the fuel pump seems to be getting power and working...could it be the fuel filter? the engine is turning over and the fuel pump is working but no fuel is making it to the engine. I am very confused. Once again thanks for the help so far but any ideas on where to go from here? Thanks
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

I will check the lines and the anti-syphon valve thanks! Also what is the right fuel filter for this year and engine? I am having a really hard time trying to figure out what filter i should use. I know this year and engine are different than most but if someone could let me know the part number I would greatly appreciate that. Thanks!
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

The anti-syphon valve is fine and fuel is making it through it and it goes up to the in-line fuel filter but not passed it. The line from the in line fuel filter to the pump is clear. I took off the fuel filter and blew into it and it was unclogged the only thing i can think of is that it was the wrong type of fuel filter and required too much pressure. I still can not find the filter that is supposed to be used on a 1992 bayliner capri 4.3L mercruiser.
 
Blk-n-Blu

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Re: 4.3 L Mercruiser not getting fuel

Does it have a carb? If so you could try disconnecting (carefully) the fuel line at the carb inlet. Behind the big carb nut at the fuel line entry point there is usually another filter. Check or replace it.
While the fuel line is disconnected from the carb put it into a jar and turn the key on briefly to see if you are pumping fuel to the carb. Be extremely careful when doing this.
The OEM filter should be this.http://www.iboats.com/Water-Separat...91805119--**********.301776756--view_id.45101
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

I will see if there is another filter near the carb. That is not the right filter. This is the problem I keep running into. If you read it specifically calls out that its not for a 92 4.3 liter that uses an inline. They give a part number but I can not find that filter. Thanks for all the help, I really appreciate it!
 
Blk-n-Blu

Blk-n-Blu

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Re: 4.3 L Mercruiser not getting fuel

This from the Marinemechanic.com:
MCM 4.3L14.3 LX With Electric Fuel Pump; DO NOT use this filter kit. The electric fuel pump and factory installed water separating fuel filter have been carefully designed to function properly together. It is not necessary or recommended to install additional fuel filters and/or water separating fuel filters on this engine. The installation of additional filters may cause:
? Fuel Vapor Locking
? Difficult Warm-Starting
? Piston Detonation Due to Lean Fuel Mixture ? Poor Drive-ability
You should only have a factory installed fuel filter between the tank and the pump.
 
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raging_gumby

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Re: 4.3 L Mercruiser not getting fuel

yeah thats what i thought. I have only a filter in between the gas tank and the fuel filter pump. I just think its the wrong size of inline fuel filter and i cant find which one i should be using. I just dont know if that would cause fuel to not make it to the carb and if so i cant fix it until i find the filter i should be using. Thanks again!
 
Blk-n-Blu

Blk-n-Blu

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Re: 4.3 L Mercruiser not getting fuel

Don't know why you are Bumping?
here is a link to the merc tech handbook and I would think the Seirra filter I linked to earlier would replace the OEM as long as the fuel lines are the same size as the inlet and outlet fittings on the filter.
http://www.boatfix.com/merc/Techbk/techcov.pdf
 
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