1992 25 Hp fuel pump

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Rudemen

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Re: 1992 25 Hp fuel pump

That float is way out of adjustment, it should be parallel with the carb casting when needle valve is seated. Second photo, depends on the load of the motor, the vacuum of the intake determines the amount of fuel, this is the High speed jet that provides the most fuel to the engine.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

got the float back to normal and the needle is seating well. thanks for all your help i am going to take the boat out next week sometime and i will update all of you.

added new highspeed jet ( #22), new fuel lines, new fuel tank, new bulb and line. so hopefuly i have it in working order.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

one more thing this motor has the primer in it and it seems to be working fine but i was wondering if this could be part of the problem? is ther a way to by pass it while testing WTO. i almose wonder if air could be getting in from thereprimer.jpg
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

Could this problem be a timing thing? At first I wouldn?t think so because it runs when I pump the bulb but after reading more in the manual I have second thoughts. I am going on the lake Monday so I just want to try to cover all my bases.
 
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Rudemen

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Re: 1992 25 Hp fuel pump

I would check the two pulse ports, one behind the fuel pump and the one below it that the hose is connected to making sure they are not clogged.

Can you blow a lot of air freely into the two Pulse ports or one and not the other with your mouth? Rig up something like a little hose or fitting of some type so that you can blow into them, if you can blow air in one and not the other turn flywheel 90 deg and take note, and then 180 deg if need be and note if they are now opposite.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

P1040640.JPGOkay i can blow air in both pulse ports. Question the one behind the fuel pump doesn't go to anything and there are threads in it. Should it be open? I know when I have the gasket behind it it blocks that hole I wonder if it does it tight enough. on the second pictuer it looks like a hole that needs to be closed. is that a worry i should be having?


See pic!!P1040639.JPG
 
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Cofe

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Re: 1992 25 Hp fuel pump

I do not know what that hole in the first picture is for. If you are getting a pulse of air out of that hole when you crank the motor, then you should plug it. The second picture is the correct hole for the pulse connection to the fuel pump. The gasket should have two mounting bolt holes with a hole between them that connects the hole on the back side of the pump to the pulse hole. That hole goes to the lower cylinder and creates a pulse with every stroke of the piston.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

Okay here is my confusion on this pulse line. The hole is ther on the motor but on the fuel pump the hole is not. If that's how it is supposed to be the so be it I just do not understand how the pulse would work.P1040642.JPG
 
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Rudemen

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Re: 1992 25 Hp fuel pump

Taylorsville said:
View attachment 143289Okay i can blow air in both pulse ports. Question the one behind the fuel pump doesn't go to anything and there are threads in it. Should it be open? I know when I have the gasket behind it it blocks that hole I wonder if it does it tight enough. on the second pictuer it looks like a hole that needs to be closed. is that a worry i should be having?


See pic!!View attachment 143288
Click to expand...

The bolt hole in the first picture is for an older style pull start safety lock out.

Where did you get this new fuel pump?

About your last post, looks like your motor is only using the bottom cylinder for fuel pump pulse. Install fuel pump, disconnect fuel line going to the carb, put fuel tank on the Floor/Ground, spin motor over and Note the amount of fuel comming out of the line that would feed the carb, a little fuel or a Lot?
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

the pump is from here Iboats and it seems to be the same as my old one. ( but this motor has alway given me the same problem)

When i turn the motor over some fuel comes out of that line not a lot i would say after 4 pulls of the rope i have one Table spoon full.
 
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Rudemen

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Re: 1992 25 Hp fuel pump

Did you test the fuel pump with Fuel Tank on the ground?


Good chance the Carb is still dirty and you probably still have Gunk behind the Low Speed needle and orifice and back under the welch plug. Spray carb cleaner thru every hole on that carb body letting it soak for several hours spray it every 30 mins in between this time period and blow everything out with compressed air.

I've cleaned carbs before and really thought they were clean only to find out they were still gunked up. While you're at it with carb off, take a look at the Reed Valves and make sure they are all flat against the leaf plate and nothing open or broken...

Lets get close up photos of all the carb parts once you disassemble it. Float, Float Needle, High and Low speed orifice, Low speed needle, gaskets, Nozzle gasket and so on.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

P1040836.jpgP1040833.JPGP1040834.jpgP1040835.JPGlast of pic here


I blew everything out with air now i will begin the carb cleaner every half hour.
 
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jasper60103

jasper60103

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Re: 1992 25 Hp fuel pump

Taylorsville said:
Okay here is my confusion on this pulse line. The hole is ther on the motor but on the fuel pump the hole is not. If that's how it is supposed to be the so be it I just do not understand how the pulse would work.View attachment 143323
Click to expand...

Looks like you've given that carb a lot of attention. Good pics.
One question though...
Did we ever get this fuel pump figured out? I don't understand why there is no pulse hole in the fuel pump?
 
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Rudemen

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Re: 1992 25 Hp fuel pump

Taylorsville said:
View attachment 143473View attachment 143474View attachment 143475View attachment 143476more pics
Click to expand...

Ok, that last picture is what we need to give attention to, top side (Low Speed) ports of this carb. On the flange side of carb that mounts to the intake of motor, look inside the throat of the carb just before the throttle valve are the little low speed ports, little holes in the top of the throat of carb need to be clear of and trash or gunk behind them.

I don't see a photo of the Slow Speed Needle removed, just wondering if it is damaged or not. It needs to be adjusted properly so that it can provide enough but not too much fuel/air mixture to raise motor RPM's enough so that their is enough vacuum/air flow for the High/Main speed jet of the carb to take over giving you more speed up to WOT.
 
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Taylorsville

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Re: 1992 25 Hp fuel pump

not yet........ the part number adds up and my old pump was the same way. with that said i have alwas had this problem though.
 
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