Fuel pump or Fuel pressure regulator???? - Maxum Boat Owners Club

jaiello · 07-26-2019, 05:03 PM

I have a 1995 2300sr with the 7.4l carb engine. I have an issue with it starting after it sits. I use the boat probably one or twice a week in the summer. The problem is when I go put it in the water. I have to pump the accelerator many times before the boat cranks. After I am in the water and running I can go to a cove and stay there for about 4 to 5 hours and the boat will crank up right away. It feels like the fuel pressure is not staying up while the boat is stored during the week. So I wanted to see if its something I can fix or check to see if the fuel pump is going or its the fuel regulator. If any of you guys have had the same issue and how you guys fixed it? Any help is appreciated. Its a pain in the butt to sit at the launch ramp for a while trying to get this thing started every time. thanks

mmwjr · 07-26-2019, 05:56 PM

A 1995 will have a mechanical fuel pump which by design has an output of around 7psi. What you describe is common for a carb engine. Try this procedure; first crank engine for a few seconds twice to ensure the carb bowl is full of fuel. Then pump the throttle twice to prime the engine and set the choke. Now crank the engine and it should start. Common for the fuel to evaporate out of the carb in summer heat after sitting.

rwc · 07-31-2019, 01:00 AM

I use the two pumps as well, but I don't do the first part of cranking it for a few seconds. Is that necessary? Doesn't pumping the throttle fill the bowl up as well?

I can usually get away with one pump if it has only been a week or so. Two if it has been longer.

This is also why I always run the blower - if that fuel is all evaporating out of the bowl, I presume it's going out through the spark arrester and straight into the engine compartment...

mmwjr · 07-31-2019, 02:00 AM

Quote:

Originally Posted by rwc

I use the two pumps as well, but I don't do the first part of cranking it for a few seconds. Is that necessary? Doesn't pumping the throttle fill the bowl up as well?

I can usually get away with one pump if it has only been a week or so. Two if it has been longer.

This is also why I always run the blower - if that fuel is all evaporating out of the bowl, I presume it's going out through the spark arrester and straight into the engine compartment...

Being that you are in cooler climate you don’t have fuel evaporating out of the carb bowl as fast as we do further south.

jaiello · 08-02-2019, 06:27 PM

I understand crank twice for a few seconds, then pump the accelerator twice. The part that I do not get is set the choke? I don't have a choke lever. Its a 7.4l mercruiser.

mmwjr · 08-02-2019, 07:45 PM

Quote:

Originally Posted by jaiello

I understand crank twice for a few seconds, then pump the accelerator twice. The part that I do not get is set the choke? I don't have a choke lever. Its a 7.4l mercruiser.

When you pump the throttle the coke will be automatically set, then as the engine warms up the choke has an electrical heating element that opens it up

jrsick · 08-02-2019, 07:48 PM

Moving the throttle will set the choke in the start position, you don't need to do anything else. Many times the choke will stay in full open position after the engine has shut down and cooled.

rwc · 08-03-2019, 12:41 AM

If I'm not mistaken, you have to pump it all the way to WOT to correctly set the choke?

mmwjr · 08-03-2019, 12:59 AM

Quote:

Originally Posted by rwc

If I'm not mistaken, you have to pump it all the way to WOT to correctly set the choke?

Nope just passed idle will do to set the choke but further is needed to prime the engine

donald · 08-03-2019, 02:20 AM

+1 On what Mike said.
Don