OMC 4.3 L Help and Question

[Capt Big]

Hi all posted on here before about a fuel pump but now I?m really worried. Let me give you some details first the motor is an OMC Stern drive 4.3 L V6 GM block. The issue I am having is no fuel to the carburetor so the obvious thing is the fuel pump which as I said I just received and will put on tomorrow, but as I was reading the directions it said if the fuel pump still isn?t drawing enough fuel it is the camshaft.

I know I still haven?t put the new pump on but it?s a real concern considering I?ve called around and have been told no one sells or makes a cam shaft for this motor anymore, I was told its obsolete. I know I could be worrying for no reason but can anyone of you guys give some advice what to do if the new fuel pump doesn?t work?

 

[Juniinc]

Re: OMC 4.3 L Help and Question

Perhaps your fuel pump is all fine,,,
Maybe problem with a fuel flow restriction.

 

[Capt Big]

Re: OMC 4.3 L Help and Question

Perhaps your fuel pump is all fine,,,
Maybe problem with a fuel flow restriction.

well i know its coming form the tank fine sucked on the hose and got fuel and I believe its going into the fuel/water seperator but can't tell due to the fact we primed it but from there nothing. When starting fluid is sparyed into the carb it wants to kick over but wont like I said new fuel pump isnt put on yet but Im still really concerned

 

[Juniinc]

Re: OMC 4.3 L Help and Question

any fuel in the vent hose on the fuel pump?

 

[Capt Big]

Re: OMC 4.3 L Help and Question

any fuel in the vent hose on the fuel pump?

nope its a manual fuel pump as well

 

[searay3]

Re: OMC 4.3 L Help and Question

in the diyers sticky there is a fuel system check procedure. A slight leak in the suction line and no fuel will come up. Make sure your lines are clean and tight, anti siphon is working properly and the fuel/water separator is sealed.

 

[searay3]

Re: OMC 4.3 L Help and Question

reread your post. Although the cam could be a concern, I would think it unlikley. Cam has a lobe that actuates the pump. Does yours have an arm or a pin. If it's the arm, be sure to dip the arm downwards when installed to clear the lobe. If the pin type, you can see the pin go in and out as you turn over the motor with the pump off.

 

[Capt Big]

Re: OMC 4.3 L Help and Question

reread your post. Although the cam could be a concern, I would think it unlikley. Cam has a lobe that actuates the pump. Does yours have an arm or a pin. If it's the arm, be sure to dip the arm downwards when installed to clear the lobe. If the pin type, you can see the pin go in and out as you turn over the motor with the pump off.

it's a pin type and I believe the pin is doing that but Ill double check tomorrow morning, but you think the cam is very unlikely

 

[searay3]

Re: OMC 4.3 L Help and Question

Not impossible, but unlikely. Question still remains, why you are changing the pump. If there is no fuel in the clear line to the carb, it would suggest the pump is ok and you may have a leak in the line. Check out the fuel test procedure.

 

[Juniinc]

Re: OMC 4.3 L Help and Question

He said, no clear line,,,
maybe a automotive fuel pump installed.

 

[Capt Big]

Re: OMC 4.3 L Help and Question

He said, no clear line,,,
maybe a automotive fuel pump installed.

well its a GM block and I just ordered a fuel pump form gotomarine.com and it matches the old one perfectly

 

[Capt Big]

Re: OMC 4.3 L Help and Question

Not impossible, but unlikely. Question still remains, why you are changing the pump. If there is no fuel in the clear line to the carb, it would suggest the pump is ok and you may have a leak in the line. Check out the fuel test procedure.

well even if not the pump which I think it is the pump is a 1988 original old and nasty so I was just going to change it out no matter what.

I will do the fuel test procedure as well, but all the hoses are newer the gentleman I bought the boat from changed them 2 years ago