1993 Sea Ray 180 BR with 4.3L Mercruiser, Model MCM Gen II with engine ID ending "3S". It has 2BBL carb. I've had this boat for only 2 weeks (my first boat) and finding things the PO either didn't tell or didn't know. Boat runs great (once started) and will run all day without issue. Problem is starting cold. I give it full throttle to set choke and then pull back to 1/4. It will start immediately and run kind of rough for about 30sec then die. Then its cranking for several minutes trying all kinds of throttle positions. Not even a hint of firing and no gas smell. Then, just when I'm sure it's not going to start, it does. Then I let it idle for a few and it runs fine for the rest of the day. Starts warm with a bump of the key.
Seems to me it's not getting fuel on cold start. So I've read many posts and my problem sounds similar to others. My understanding is that the fuel pump should run while cranking regardless of oil pressure switch. I jumpered the purple/purple-yellow wires on the oil pressure switch so that I could try to run the pump with key on/engine off. When I turned the key on, I could hear a single click from the pump. I double checked my jumper and tried again. Still a single click. So I cycle on and off about 10 times then the pump starts running. So now I'm thinking the fuel pump is "sticky" when it sits for awhile and then once it breaks free, it's fine for the rest of the day?
So my question is now, does the fuel pump run continuous or does it shut down after reaching a certain operating pressure similar to automotive pumps? With the oil pressure switch bypassed, should it start running immediately when keyed on and keep running? I want to make sure it is the problem before dropping a couple hundred for a new pump.
Thanks in advance!
Seems to me it's not getting fuel on cold start. So I've read many posts and my problem sounds similar to others. My understanding is that the fuel pump should run while cranking regardless of oil pressure switch. I jumpered the purple/purple-yellow wires on the oil pressure switch so that I could try to run the pump with key on/engine off. When I turned the key on, I could hear a single click from the pump. I double checked my jumper and tried again. Still a single click. So I cycle on and off about 10 times then the pump starts running. So now I'm thinking the fuel pump is "sticky" when it sits for awhile and then once it breaks free, it's fine for the rest of the day?
So my question is now, does the fuel pump run continuous or does it shut down after reaching a certain operating pressure similar to automotive pumps? With the oil pressure switch bypassed, should it start running immediately when keyed on and keep running? I want to make sure it is the problem before dropping a couple hundred for a new pump.
Thanks in advance!