Fuel pump replacement...

further

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If one was to replace the fuel pump, is it a straightforward swap or is there anything else I should be aware of? Priming, etc? How does that work if turning the key doesn't energize the pump? I've read several posts that mention jumping the relay but I'm not clear on exactly how that is done. Can someone walk me through this please?
Much appreciated
 

Scott Danforth

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mechanical or electrical?

assuming electrical

if electrical, there are two paths to powering the relay. one is the crank circuit for teh starter, the other is the oil pressure switch.
 

further

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Thanks for the info Scott, it's electric. 96 4.3l GS. Still not understanding though.
 

Scott Danforth

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most of the time there are electrical connection issues with electric fuel pumps and the pump itself is just fine.

regarding your pump, unbolt, unplumb, install new pump, plumb new pump. turn key, go boating.......unless your issue is an electrical connection.

as for jumping the relay, the schematic for the relay is on the side of it. if it is a VF-4 style relay, the coil is terminals 85 and 86. the load terminals are 30, 87, and 87a. jumper terminal 30 and 87 in the relay socket with appropriate 10 gauge wire with 1/4" male quick disconnect terminals
 

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Ok so I just jumpered the 30 and 87 terminals and pump runs. I removed the fuel supply to the carb from the pump and jumpered to see if fuel would come out and nothing.... assuming this means pump is no good?
 

Bondo

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assuming this means pump is no good?

Nope,.... Not yet,.... Ya gotta prove that fuel is available to the pump, from the tank 1st,....
 

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Nope,.... Not yet,.... Ya gotta prove that fuel is available to the pump, from the tank 1st,....


So tank is full, anti siphon valve was replaced bout 3 seasons ago along with all the fuel lines. How to confirm all is in order? Guess the anti-siphon could go bad?

As an aside, i do complete maintenance at the end of every season so fuel filter is fresh (well 25 or so hours of use this season)...
 

dypcdiver

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Without being too cavalier, just suck it and see. Oh, and don't smoke for a while.
 

further

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Without being too cavalier, just suck it and see. Oh, and don't smoke for a while.

Hmmm yeah i've got fuel in the filter up to where the pump sits so am going to assume supply to the pump is fine. Changing out the pump....
Thanks
 

further

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Replaced the fuel pump this evening along with the relay and she fired right up. All is good in the world :)

Another question for ya'll... Since I had the carb rebuilt, I'm getting more smoke through the exhaust - not a crazy amount but more than I ever remember before the carb was rebuilt. Is this normal?

 

Thalasso

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That isn't smoke It's steam. The water is colder then the exhaust temp
 
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