[ATTACH=CONFIG]526621[/ATTACH][ATTACH=CONFIG]526622[/ATTACH]Rebuilt Gen 5 502 Mag Carbureted
I changed the oil after the initial run because some fuel dumped in to the motor because of a float boat screw up.
The filter that I bought based on the various cross reference web sites turned out to have too large of a threaded opening so I used one from a car that matched the thread but its real short. I assume that the remote filter holder may have been changed at some point which is why it didn't match the serial number search specs. (Who Knows what kind of Frankenstein motor I have) I understand from reading this forum that the issue may be caused by internal issues and the right thing to do is to follow the oil pressure advice regarding a 30 lb bypass etc which I plan on doing once I fully understand the process.
I would like to know if these "first steps" are correct.

1. change the filter to a high quality filter
2. change the oil to a high quality oil (I currently have Sierra 20 50) what do you recommend?
3. switch the sending unit with a known good working one (I have one)

The current gauge reads just above 20 at low idle then goes to about 40-50 at 4000 rpm, they are the most entry level line of Faria gauges available but they are new.
The filter that fits on it uses a thread of 13/16-16 (maybe that's the problem?)
There is only 5" clearance to the contact point of the manifold, can you recommend a product that will allow me to mount it higher? Same for the fuel separator, its very close to the fuel pump. I have space on the bilge wall and I have clearance if they made an adaptor to "lift" them

Thanks in advance for your responses

What was the oil pressure before the oil change? I wouldn't have even started the engine until I knew I had the right filter on it, so I would start with that.

I did a cross reference of your AC Delco #PF454CL with NAPA's site and got Napa Gold (which is a Wix) #7099.

It shows it's specs as:
Beta Ratio : 2/20=6/20
Filter O.D. (Inches) : 3.66"
Flow Rate : 9 - 11 gpm
Gasket I.D. (Inches) : 3.1"
Gasket O.D. (Inches) : 3.444"
Height (Inches) : 3.306"
Media Type : Glass Enhanced Cellulose
Style : Spin-On Lube Filter
Thread Size (Inches) : 13/16 - 16
Burst Pressure : 245 psi
Filter O.D. (mm) : 92 mm
Gasket I.D. (mm) : 79 mm
Gasket O.D. (mm) : 87 mm
Height (mm) : 84 mm

and the following as part of it's application list:
Mercruiser Marine 5.7L 210 hp 5.7 L 350 CID V8 4 Stroke 1996 - 1997
Mercruiser Marine 5.7L 215 hp Competition Ski 5.7 L 350 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 5.7L 220 hp EFI 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 230 hp 5.7 L 350 CID V8 4 Stroke 1989 - 1992
Mercruiser Marine 5.7L 235 hp 5.7 L 350 CID V8 4 Stroke 1993 - 1995
Mercruiser Marine 5.7L 240 hp 5.7 L 350 CID V8 4 Stroke 1989 - 1991
Mercruiser Marine 5.7L 240 hp Magnum 5.7 L 350 CID V8 4 Stroke 1989 - 1991
Mercruiser Marine 5.7L 250 hp 5.7 L 350 CID V8 4 Stroke 1992 - 1995
Mercruiser Marine 5.7L 250 hp 5.7 L 350 CID V8 4 Stroke 1998 - 2007
Mercruiser Marine 5.7L 250 hp BlueWater 5.7 L 350 CID V8 4 Stroke 1989 - 1995
Mercruiser Marine 5.7L 250 hp Competition Ski 5.7 L 350 CID V8 4 Stroke 1989 - 1995
Mercruiser Marine 5.7L 250 hp EFI 5.7 L 350 CID V8 4 Stroke 1995 - 1995
Mercruiser Marine 5.7L 250 hp LX 5.7 L 350 CID V8 4 Stroke 1996 - 1997
Mercruiser Marine 5.7L 250 hp LX EFI 5.7 L 350 CID V8 4 Stroke 1996 - 1997
Mercruiser Marine 5.7L 250 hp Magnum 5.7 L 350 CID V8 4 Stroke 1992 - 1997
Mercruiser Marine 5.7L 250 hp TKS 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 255 hp MIE 5.7 L 350 CID V8 4 Stroke 1980 - 1980
Mercruiser Marine 5.7L 260 hp 5.7 L 350 CID V8 4 Stroke 1980 - 1988
Mercruiser Marine 5.7L 260 hp 5.7 L 350 CID V8 4 Stroke 1997 - 2007
Mercruiser Marine 5.7L 260 hp BlueWater 5.7 L 350 CID V8 4 Stroke 1986 - 1988
Mercruiser Marine 5.7L 260 hp BlueWater 5.7 L 350 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 5.7L 260 hp Competition Ski 5.7 L 350 CID V8 4 Stroke 1988 - 1988
Mercruiser Marine 5.7L 260 hp Competition Ski 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 260 hp EFI 5.7 L 350 CID V8 4 Stroke 1998 - 2002
Mercruiser Marine 5.7L 260 hp MIE 5.7 L 350 CID V8 4 Stroke 1981 - 1985
Mercruiser Marine 5.7L 260 hp Ski 5.7 L 350 CID V8 4 Stroke 1986 - 1987
Mercruiser Marine 5.7L 260 hp TKS 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 260 hp Tow Sports TKS 5.7 L 350 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 5.7L 265 hp Magnum EFI 5.7 L 350 CID V8 4 Stroke 1995 - 1995
Mercruiser Marine 5.7L 265 hp Magnum EFI Tournament 5.7 L 350 CID V8 4 Stroke 1995 - 1995
Mercruiser Marine 5.7L 265 hp Magnum EFI Tournament Ski 5.7 L 350 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 5.7L 265 hp Magnum Tournament Ski 5.7 L 350 CID V8 4 Stroke 1992 - 1997
Mercruiser Marine 5.7L 270 hp 5.7 L 350 CID V8 4 Stroke 1999 - 2007
Mercruiser Marine 5.7L 270 hp 350 Magnum 5.7 L 350 CID V8 4 Stroke 1987 - 1988
Mercruiser Marine 5.7L 280 hp 350 Magnum EFI Gen+ 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 280 hp 350 Magnum MPI Ski 5.7 L 350 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 5.7L 280 hp LX EFI Gen+ 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 290 hp LX EFI Gen+ 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 290 hp Magnum EFI Gen+ 5.7 L 350 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 5.7L 300 hp 350 Mag 5.7 L 350 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 5.7L 300 hp Horizon 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 300 hp Magnum Axius 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 300 hp Magnum Axius SeaCore 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 300 hp Magnum MPI 5.7 L 350 CID V8 4 Stroke 1998 - 2008
Mercruiser Marine 5.7L 300 hp Magnum MPI Gen+ 5.7 L 350 CID V8 4 Stroke 1996 - 1997
Mercruiser Marine 5.7L 300 hp Magnum MPI Horizon 5.7 L 350 CID V8 4 Stroke 2000 - 2007
Mercruiser Marine 5.7L 300 hp Magnum SeaCore 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 300 hp MPI 5.7 L 350 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 5.7L 300 hp Tempest 5.7 L 350 CID V8 4 Stroke 1985 - 1986
Mercruiser Marine 5.7L 300 hp Tow Sports MPI 5.7 L 350 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 5.7L 315 hp Black Scorpion 5.7 L 350 CID V8 4 Stroke 1997 - 1998
Mercruiser Marine 5.7L 315 hp Magnum MPI 5.7 L 350 CID V8 4 Stroke 1999 - 2007
Mercruiser Marine 5.7L 320 hp EFI 5.7 L 350 CID V8 4 Stroke 1987 - 1989
Mercruiser Marine 5.7L 330 hp Black Scorpion 5.7 L 350 CID V8 4 Stroke 1999 - 2007
Mercruiser Marine 5.7L 330 hp Scorpion 5.7 L 350 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 5.7L Scorpion 5.7 L 350 CID V8 4 Stroke 2008 - 2008
Mercruiser Marine 5.7L Tow Sports MPI 5.7 L 350 CID V8 4 Stroke 2008 - 2008
Mercruiser Marine 6.2L 320 hp Horizon 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp Magnum 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp Magnum Axius 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp Magnum Axius SeaCore 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp Magnum SeaCore 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp MPI 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 320 hp MX MPI 6.2 L 377 CID V8 4 Stroke 2001 - 2007
Mercruiser Marine 6.2L 320 hp MX MPI Horizon 6.2 L 377 CID V8 4 Stroke 2002 - 2007
Mercruiser Marine 6.2L 340 hp MX Black Scorpion 6.2 L 377 CID V8 4 Stroke 2002 - 2007
Mercruiser Marine 6.2L 340 hp Scorpion 6.2 L 377 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 6.2L 360 hp Scorpion 6.2 L 377 CID V8 4 Stroke 1998 - 1998
Mercruiser Marine 6.2L 380 hp Scorpion 377 HO 6.2 L 377 CID V8 4 Stroke 2009 - 2009
Mercruiser Marine 6.2L Scorpion HO 6.2 L 377 CID V8 4 Stroke 2008 - 2008
Mercruiser Marine 7.4L 300 hp 7.4 L 454 CID V8 4 Stroke 1989 - 1997
Mercruiser Marine 7.4L 300 hp LX EFI 7.4 L 454 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 7.4L 310 hp 7.4 L 454 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 7.4L 310 hp BlueWater 7.4 L 454 CID V8 4 Stroke 1991 - 1996
Mercruiser Marine 7.4L 310 hp EFI 7.4 L 454 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 7.4L 310 hp MPI 7.4 L 454 CID V8 4 Stroke 1998 - 2000
Mercruiser Marine 7.4L 330 hp 7.4 L 454 CID V8 4 Stroke 1985 - 1988
Mercruiser Marine 7.4L 330 hp BlueWater 7.4 L 454 CID V8 4 Stroke 1989 - 1990
Mercruiser Marine 7.4L 330 hp LX MPI 7.4 L 454 CID V8 4 Stroke 1996 - 1997
Mercruiser Marine 7.4L 330 hp Magnum 7.4 L 454 CID V8 4 Stroke 1987 - 1987
Mercruiser Marine 7.4L 330 hp MIE 7.4 L 454 CID V8 4 Stroke 1980 - 1980
Mercruiser Marine 7.4L 330 hp TR 7.4 L 454 CID V8 4 Stroke 1982 - 1987
Mercruiser Marine 7.4L 330 hp TRS 7.4 L 454 CID V8 4 Stroke 1982 - 1987
Mercruiser Marine 7.4L 340 hp BlueWater 7.4 L 454 CID V8 4 Stroke 1986 - 1988
Mercruiser Marine 7.4L 340 hp MIE 7.4 L 454 CID V8 4 Stroke 1981 - 1985
Mercruiser Marine 7.4L 340 hp MPI 7.4 L 454 CID V8 4 Stroke 1997 - 1997
Mercruiser Marine 7.4L 340 hp MPI BlueWater 7.4 L 454 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 7.4L 350 hp EFI BlueWater 7.4 L 454 CID V8 4 Stroke 1995 - 1995
Mercruiser Marine 7.4L 350 hp Magnum 7.4 L 454 CID V8 4 Stroke 1991 - 1997
Mercruiser Marine 7.4L 360 hp Magnum 7.4 L 454 CID V8 4 Stroke 1989 - 1990
Mercruiser Marine 7.4L 365 hp Magnum 7.4 L 454 CID V8 4 Stroke 1988 - 1988
Mercruiser Marine 7.4L 370 hp 7.4 L 454 CID V8 4 Stroke 1980 - 1987
Mercruiser Marine 7.4L 380 hp Magnum MPI Horizon 7.4 L 454 CID V8 4 Stroke 1998 - 2000
Mercruiser Marine 7.4L 385 hp Magnum EFI 7.4 L 454 CID V8 4 Stroke 1994 - 1995
Mercruiser Marine 7.4L 385 hp Magnum MPI 7.4 L 454 CID V8 4 Stroke 1996 - 2000
Mercruiser Marine 7.4L 395 hp Magnum EFI Tournament Ski 7.4 L 454 CID V8 4 Stroke 1994 - 1995
Mercruiser Marine 7.4L 395 hp Magnum MPI Ski 7.4 L 454 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 7.4L 400 hp 7.4 L 454 CID V8 4 Stroke 1980 - 1986
Mercruiser Marine 7.4L 420 hp 7.4 L 454 CID V8 4 Stroke 1987 - 1989
Mercruiser Marine 7.4L 440 hp TRS 7.4 L 454 CID V8 4 Stroke 1983 - 1986
Mercruiser Marine 8.1L 370 hp Horizon 8.1 L 496 CID V8 4 Stroke 2001 - 2004
Mercruiser Marine 8.1L 370 hp Horizon 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 370 hp Horizon S 8.1 L 496 CID V8 4 Stroke 2005 - 2007
Mercruiser Marine 8.1L 375 hp Magnum 8.1 L 496 CID V8 4 Stroke 2001 - 2010
Mercruiser Marine 8.1L 375 hp Magnum Axius 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 375 hp Magnum Axius SeaCore 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 375 hp Magnum SeaCore 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 420 hp HO 8.1 L 496 CID V8 4 Stroke 2001 - 2004
Mercruiser Marine 8.1L 420 hp HO 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 420 hp HO S 8.1 L 496 CID V8 4 Stroke 2005 - 2007
Mercruiser Marine 8.1L 425 hp High Output 8.2 L 502 CID V8 4 Stroke 2009 - 2009
Mercruiser Marine 8.1L 425 hp Magnum HO 8.1 L 496 CID V8 4 Stroke 2001 - 2010
Mercruiser Marine 8.1L 425 hp Magnum HO Axius 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 425 hp Magnum HO Axius SeaCore 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.1L 425 hp Magnum HO SeaCore 8.1 L 496 CID V8 4 Stroke 2008 - 2010
Mercruiser Marine 8.2L 375 hp Horizon 8.2 L 502 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 8.2L 380 hp Magnum 8.2 L 502 CID V8 4 Stroke 2009 - 2010
Mercruiser Marine 8.2L 400 hp BlueWater 8.2 L 502 CID V8 4 Stroke 1991 - 1995
Mercruiser Marine 8.2L 400 hp MPI 8.2 L 502 CID V8 4 Stroke 1997 - 2000
Mercruiser Marine 8.2L 400 hp MPI BlueWater 8.2 L 502 CID V8 4 Stroke 1996 - 1996
Mercruiser Marine 8.2L 410 hp BlueWater 8.2 L 502 CID V8 4 Stroke 1989 - 1990
Mercruiser Marine 8.2L 410 hp Magnum 8.2 L 502 CID V8 4 Stroke 1989 - 1993
Mercruiser Marine 8.2L 415 hp Magnum EFI 8.2 L 502 CID V8 4 Stroke 1994 - 1997
Mercruiser Marine 8.2L 415 hp Magnum MPI 8.2 L 502 CID V8 4 Stroke 1998 - 2000
Mercruiser Marine 8.2L 425 hp HO 8.2 L 502 CID V8 4 Stroke 2010 - 2010
Mercruiser Marine 8.2L 430 hp Magnum High Output 8.2 L 502 CID V8 4 Stroke 2009 - 2010

the picture in the post shows a stock merc oil filter head.go get a merc filter from your local merc dealer and install it.if you washed the cylinders with gas due to a stuck float the pressure will drop due to the gas dilution.

Is 20lbs at idle and 40-50lbs @4000rpm is that the reading when its hot?

Ive always used Mobil 1 15x-50 and never had a problem

Thanks guys
SB thats an awesome list I got the wixx in a slightly taller size
Mike I already changed it after the potential wash down but with a pump not draining it (no room for a pan)
Satisfaction the oil pressure was slightly lower after the wash down and before the oil change
I am going to put in the new filter and oil and sending unit and check, then Ill be looking for clarity on the bypass mods
I chose kendall q1 20/50

AC Delco Makes actually three different lenght filters that fit numerous applications, as the list suggests. I actually have a cross referenced chart I made on my won between K&N, AC Declo and Fram filters. Now I just gotta find it.

I always like running the biggest filter I can for my application. We run the tallest filteres we can on out street/ strip engines. I'd do the same for the boats too, as long as you have the realestate to give up.

That list would make a great sticky, filters, plugs, etc..
not oyel lol!

make sure you dont have the oil filter lines reversed..and the oil pressure is suitable to be ok running..all you really need is 7 psi for every 1000 rpms.. i would put a mechanical gauge on it for correct numbers.. i spin my smappblock in my donzi to 6200 and a max 50 psi of oil pressure..after a good run it will idle at 10 psi then it will go to 20 psi after a few minutes when the oil cools odd a bit..