1996 Four Winns 5.8 Duo drive Fuel pump location

[lvhdude]

I am looking to swap out the fuel injection system on my 5.8 Mercruiser (Ford) for an aluminum manifold and a good old fashioned Holley 600. I just can't get it to idle down below 1100 RPM. My question (s) are where is the fuel pump located, assuming I'll need something with a lower pressure, like 5-7 lbs, what's a good replacement, and does the distributor need any input from the ECU to operate? Or will I need to source a stand alone unit for that? Anyone tackle this in the past? How much of the electronics can I strip off the engine and have everything else function property? And yes I've looked for vacuume leaks, replaced the upper manifold gasket, the IAC and the TPS, checked throttle plate adjustment. I put a plastic plug in the hole in the throttle plate which got it down to 1100 or so, but it's still too fast to shift in and out of gear well. Thanks in advance.

 

[pae0332]

isnt this a volvo penta engine?
if the pump is putting out too much pressure, fuel will flow out of the top vent. and flood the the engine. it will not make the engine run at high idle. put a gauge on it.
that being said, if the pump is the original EFI pump, yeah, you need one for a carb.
if it is a V/P the fuel pump is typically mounted to the back of the engine, you really cant miss it.

bottom line is you need a thunderbolt or ESD ignition system, you can remove the ecu and all the EFI wiring, strip it a all down to bare bones but you have to ad a fuel pump circuit that feeds off of the oil pressure. you can google how to go that,
and you need to wire the shift interrupt circuit into the ignition system.

 

[Scott Danforth]

have you check your IAC to see if its stuck. that will cause the motor to not idle correctly

if you are going to carb......

you have to run a marine intake with brass water passages. not a standard aluminum intake unless your motor is heat exchanged cooled.

Carter universal marine fuel pump for fuel supply to carb. wire it as per the typical VP system using the diodes from the alternator, or with an oil pressure switch and relay. you need more than 600 CFM. 600 CFM is what is on a V6. I would shoot for 650-700 CFM on the stock ford. VP put 715 CFM carbs on 350's in the late 80's early 90's

as for the distributor, yes, you need a non EFI distributor. I would look at the Mallory YLM-554-CV (used or get the new ones at a higher price thru Sierra)

 

[alldodge]

The 5.8 is a VP and I moved thread to VP

The fuel pump is electric and is on top the motor inside a casting with a lid. Follow the fuel line from TB

 

[lvhdude]

isnt this a volvo penta engine?
if the pump is putting out too much pressure, fuel will flow out of the top vent. and flood the the engine. it will not make the engine run at high idle. put a gauge on it.
that being said, if the pump is the original EFI pump, yeah, you need one for a carb.
if it is a V/P the fuel pump is typically mounted to the back of the engine, you really cant miss it.

bottom line is you need a thunderbolt or ESD ignition system, you can remove the ecu and all the EFI wiring, strip it a all down to bare bones but you have to ad a fuel pump circuit that feeds off of the oil pressure. you can google how to go that,
and you need to wire the shift interrupt circuit into the ignition system.

Opps, brain fart, yes it is a V/P. It is EFI at the moment, and runs perfectly except for not idling down like it should. I don't think there's a "top" for it to leak fuel from. Yes if it were Carbed and had the EFI pump it would surely leak fuel and flood. The EFI pump should have an electrical source that should power a lower pressure pump for a carb? Was thinking I could just trade one for the other? What does the shift interrupt circuit do? That's new to me. Thanks.

 

[lvhdude]

have you check your IAC to see if its stuck. that will cause the motor to not idle correctly

if you are going to carb......

you have to run a marine intake with brass water passages. not a standard aluminum intake unless your motor is heat exchanged cooled.

Carter universal marine fuel pump for fuel supply to carb. wire it as per the typical VP system using the diodes from the alternator, or with an oil pressure switch and relay. you need more than 600 CFM. 600 CFM is what is on a V6. I would shoot for 650-700 CFM on the stock ford. VP put 715 CFM carbs on 350's in the late 80's early 90's

as for the distributor, yes, you need a non EFI distributor. I would look at the Mallory YLM-554-CV (used or get the new ones at a higher price thru Sierra)

Replaced the IAC with new, no difference. Are you saying that corrosion will be an issue with aluminum? Or is that a salt/brine water issue? Not heat exchange cooled. A 351 C.I. engine at 6,000 RPM will displace 610 CFM at 100% efficiency, which nothing naturally aspirated will. Chevrolet ran a 670 (rated) Holley on their 325 HP 396 and 360 HP 427 in 1966. But in fact it's still a 600 Holley. Holley sells the 600 as a 670 today because people tend so much to go oversize on carbs, but I got a pile of em if it's not enough. What is the marine requirement for distributors? Not vented to the outside? Waterproofed? Unique cap and rotor design? Thanks, Joe.

 

[Scott Danforth]

You need a marine intake for corrosion issues, even in fresh water

You need a marine carb and marine distributor so you don't blow up and meet Jesus

We will agree to disagree on carb size for a boat.

And you can't use any of the carbs from your pile of carbs as none of them are marine

 

[lvhdude]

Scott, thanks for the education, I see there are differences between automotive and marine stuff. Maybe I should be working harder to find the idle issue on my EFI. I'm just at a bit of a loss as to where I go from here. I suppose pulling the lower intake and looking for possible air leaks is the next step. Everything I read on MAP sensors doesn't indicate idle speed issues, and the IAC and TPS sensors made no difference. Throttle cable and TB air valve adjustments are good. Can't find issues spraying brake cleaner around the gaskets. I'm looking for the OBD test port and will see if there are codes when I locate the proper scanner. Again, thanks to everyone for the guidence.

 

[Scott Danforth]

Check idle with throttle cable disconnected