Electric Fuel Pump Issues?

PlayDate said:
I'm just shaking my head when I hear stories like this. Fortunately the owner has a great friend who can fix anything ready to help her.:)


Reading your list......

It would appear that the work and early performance issues were related to the plug wires crossed. Rookie error by the "mechanic" and who in the world replaces a cap without replacing the rotor?

The problem you are chasing now appears to be the carb running out of gas. My money is on the float level of the carb. The fluid tests indicate that the pump is performing and while air could be getting in......I just have a feeling the float is the issue.

In regards to the fuel pressure set up.......There usually is a spare port on the spin on fuel filter mounting that is on the pressure side. It is an easy way to tap the line if it has one.
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Yes I feel badly for her. And, she knows her boat to a point.
There isn't a filter that I know of downstream of the pump other than the screen in the carb. Only the filter/water separator on the suction side. I gotta tell that I've only built a thousand carbs but as Regan said "trust but verify".
 
I have done a lot as well but in some cases the rebuild kits include a float valve needle and seat which is the wrong length (too long).

I have had to stop having a cocktails while doing carb rebuilds because you have to check every part and gasket now. ;)
 
@ttmott I still think you should do a volume check of the pump and let it run into a bucket and see if or when it dies. That sounds like an easy test, and one that might tell you if the pump is heating up and dying.
 
PlayDate said:
I have done a lot as well but in some cases the rebuild kits include a float valve needle and seat which is the wrong length (too long).

I have had to stop having a cocktails while doing carb rebuilds because you have to check every part and gasket now. ;)
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I always arrange the parts and pieces including gaskets removed off to the side and compare just about every item in the kit to what was removed. It was a Sierra kit and oddly had no data sheet. We had to set the float level via internet search. Just about every kit I've used supported a multitude of different carbs. The "quadraflushes" were the worst in extra pieces.
 
SKybolt said:
@ttmott I still think you should do a volume check of the pump and let it run into a bucket and see if or when it dies. That sounds like an easy test, and one that might tell you if the pump is heating up and dying.
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We'll do that if the filter/separator she wants to change doesn't do the trick. Still the boat ran just fine then two days later runs badly after her service was done.
 
ttmott said:
We'll do that if the filter/separator she wants to change doesn't do the trick. Still the boat ran just fine then two days later runs badly after her service was done.
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Yeah, I mean, I am with John in that it should have something to do with what the mechanic(s) did. But common sense tells me finding the issue will lead you to that anyway.

If you didn't see the carb run dry, I wouldn't even go there and focus on what could the mechanic possibly have done. But doing that test will rule out a lot of things and it's super easy to do.

EDIT: It's unclear to me if you rebuilt the carb or not, but it's starting to sound like you did. Is it possible that the new float was bigger then the original and it's getting stuck closed some how?
 
SKybolt said:
EDIT: It's unclear to me if you rebuilt the carb or not, but it's starting to sound like you did. Is it possible that the new float was bigger then the original and it's getting stuck closed some how?
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I did. Like I said earlier I always arrange the removed pieces off to the side and compare with the new replacement pieces. Float level isn't rocket science and in reality if it was incorrectly adjusted within a range it wouldn't run out of fuel. The only thing would be the mixture wouldn't be as designed. The float level sets the fuel level in the emulsion tubes which establishes the correct fuel/air emulsion. Each engine and it design vacuum requires differences in that fuel that is passed through the venturis.
 
ttmott said:
I did. Like I said earlier I always arrange the removed pieces off to the side and compare with the new replacement pieces. Float level isn't rocket science and in reality if it was incorrectly adjusted within a range it wouldn't run out of fuel. The only thing would be the mixture wouldn't be as designed. The float level sets the fuel level in the emulsion tubes which establishes the correct fuel/air emulsion. Each engine and it design vacuum requires differences in that fuel that is passed through the venturis.
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It was just a thought. When I was younger I worked for a carburetor shop. I was their specialty guy for foreign and marine carbs. I have seen floats get stuck in the closed position and then fix them selves because of a jolt. Much like the angle changing in a boat coming off plane. Was just a thought.
 
SKybolt said:
It was just a thought. When I was younger I worked for a carburetor shop. I was their specialty guy for foreign and marine carbs. I have seen floats get stuck in the closed position and then fix them selves because of a jolt. Much like the angle changing in a boat coming off plane. Was just a thought.
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Got it no issues; I thought you said float level; as I re-read it as float sticking. Plan A is the filter/water separator. Plan B is the Float and screen. Plan C is the bucket and measure pressure/flow.
 
It is hard to imagine the filter/water separator would have anything to do with it since the pump appears to be working pulling/pushing gas. Short of an air leak.....that seems less likely than number 2.

When you said the accelerator pump was dry.....that keeps bringing me back to the carb.

You have probably already checked these things.....the fuel vent and how much gas is in the tank are also things that could create a similar problem. If you do move to number 2 that is the perfect time to go to Home Depot and pick up a couple of fittings so that you can install a pressure test port.:)
 
Take it back to who worked on it and leave it there block other boats. They will get on it
 
PlayDate said:
It is hard to imagine the filter/water separator would have anything to do with it since the pump appears to be working pulling/pushing gas. Short of an air leak.....that seems less likely than number 2.

When you said the accelerator pump was dry.....that keeps bringing me back to the carb.

You have probably already checked these things.....the fuel vent and how much gas is in the tank are also things that could create a similar problem. If you do move to number 2 that is the perfect time to go to Home Depot and pick up a couple of fittings so that you can install a pressure test port.:)
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The tank is full. Fuel is good. She uses the boat a couple of times a week water skiing. When I go over there tomorrow I'll look at what fittings will be needed for pressure. I most likely have all that are needed in the shop.
More research on the float level - 3/8 inch to top gasket if the needle does not have a spring and 9/16 if it does have a spring. It has a spring. Big difference. I'm going to double check our setting even though she only wants to change the filter/separator for this try.
 
I think we have it solved - look how far the needle is above the retainer/seat causing the float level to be at the bottom of the bowl. It looks like the rubber tip has swelled up significantly- it is over double the size of the one we took out.
She is going to run the boat and let me know. I put the old needle and seat back in.
IMG_7739.jpeg
 
One word: China


It is going to scream now just in time for the 4th.
 
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