fuel presure question

[bayman1948]

I have a 1985 75 hp evenrude. I think I am having problems with the engine getting rich after running and then won't idle good enough to shift when I slow down. It seems like the primer choke is leaking but I took off and tried it on a battery and blew thru when it was acuated and it wouldn't pass air and when I disconected from a battery it shut down the air. I am wondering how much presure the pump has and if maby under presure then the choke would leak. Anyone out there know the presures there ought to be and maby have an idea of what I should look out for? I need to be firshing with this boat instead of working on it.

 

[ezeke]

Re: fuel presure question

The primer solenoid is only supposed to cold start the engine and is activated by pushing in the ignition key. If the red handle on the primer solenoid is turned at 90? from the solenoid, turn it in line with the cylindrical solenoid. ​

 

[bayman1948]

Re: fuel presure question

I guess that I am asking if there could be enough presure from the fuel pump to overide the primer if the primer was somehow weak, Also would like to know just how much presure the pump puts out.

 

[dsinger]

Re: fuel presure question

Ok lets call the primer solenoid a choke instead. Its only function is to start your motor for the sake of being simple. The fuel pump and primer solenoid deliever fuel to different places so no it will not over ride it. Rebuild your fuel pump or clean the filter first. Rebuild kits are cheap and easy. What does the primer ball feel like after you run it when it wont ideal

 

[ezeke]

Re: fuel presure question

Fuel pump pressure is 1-3 psi. All the fuel pump does is supply fuel to the float bowls, and provide the supply for the primer solenoid when required.

The action of the pistons pulls the fuel and air through the carburetors. If the orifices are clogged, all the engine will get is air.​