Had an identical problem with 2 different engines.

Either going to be heads, head gaskets, or poorly sealed intake manifold.

Ron

"jamesgangnc" wrote in message
oups.com...
If it has oil pressure now and didn't then it sounds like the pump was
sucking air for some reason. That could be that the oil is not
getting back to the pan fast enough. Or the pickup fell off the oil
pump. Another possible explanation is that the relief valve on the
pump got stuck open for some reason.

Eisboch wrote:
"Big gus" wrote in message
...
Hi and thanks for the speedy response

its was just the heads and a valve job. the head gaskets were
replaced.

the engine was warm when I changed the oil filter.

the oil pressure started to drop after I put the engine under a load.
3500 RPM's and the oil pressure dropped to zero and the red warning
light on the dash board went off


Hate it when that happens. Forget everything I suggested. You have a
problem.

Eisboch

On Thu, 24 Aug 2006 13:07:27 -0400, "Eisboch"
wrote:

You have a
problem.

Ayyyup, big time.

With all the work you had done I would remove the oil pan and check to see
if the oil pump pickup screen got crap in it from taking the engine apart.


"Big gus" wrote in message
...
Help!!!

Hi all

anyone had this problem?

I have a twin engine searay
with 454's


I just hand the heads , valve's, new rocker arms, and valve springs
done in the one engine

I ran the boat at the dock for a good 8 house with no issues. I even
changed the oil several times just to be sure


I took the boat out last night and after running under load for about
15 minutes the engine in question started to lose oil pressure.

At once I shut the motor down.

I got back to the dock expecting to see oil sprayed all over my engine
compartment, but I found nothing, no leaks drips or any sigh of oil
leakage

Checked the dip stick and it was fill and very clean.

well I got back to my slip and took a look at the oil filer , it
seemed to have some stuff in it as I assumed that it would, so I
changed it, and re started the motor.

As the filter filled the oil pressure gauge jumped up, but not as high
as it should.


Anyone got any thoughts ?

on why all of a sudden I got no oil pressure?

Thanks
M

Big gus wrote:
Help!!!

Hi all

anyone had this problem?

I have a twin engine searay
with 454's


I just hand the heads , valve's, new rocker arms, and valve springs
done in the one engine

I ran the boat at the dock for a good 8 house with no issues. I even
changed the oil several times just to be sure


I took the boat out last night and after running under load for about
15 minutes the engine in question started to lose oil pressure.

At once I shut the motor down.

I got back to the dock expecting to see oil sprayed all over my engine
compartment, but I found nothing, no leaks drips or any sigh of oil
leakage

Checked the dip stick and it was fill and very clean.

well I got back to my slip and took a look at the oil filer , it
seemed to have some stuff in it as I assumed that it would, so I
changed it, and re started the motor.

As the filter filled the oil pressure gauge jumped up, but not as high
as it should.


Anyone got any thoughts ?

on why all of a sudden I got no oil pressure?

Thanks
M

You said the oil pressure went down to zero. Sounds kind of strange.
A friend in the marine business once told me that a problem like this
(one that occurs after the engine was worked on) is always related some
how to the last repair. I would guess they might have bumped the oil
pressure sending unit or its wire. Give the wire a look and see if its
a tight fit. Before I did anything major at this point, if the
sending unit and wire looks OK, I would replace the sending unit and/or
remove the sending unit and temporarily attach a mechanical guage to
the engine and get a real pressure reading. The reasoning behind this
if the face you said the enging sounded fine even after the pressure
went down to zero.

Regards, Bob

"Eldon" wrote in message
oups.com...


You said the oil pressure went down to zero. Sounds kind of strange.
A friend in the marine business once told me that a problem like this
(one that occurs after the engine was worked on) is always related some
how to the last repair. I would guess they might have bumped the oil
pressure sending unit or its wire. Give the wire a look and see if its
a tight fit. Before I did anything major at this point, if the
sending unit and wire looks OK, I would replace the sending unit and/or
remove the sending unit and temporarily attach a mechanical guage to
the engine and get a real pressure reading. The reasoning behind this
if the face you said the enging sounded fine even after the pressure
went down to zero.

Regards, Bob


What he said.

Eisboch

I agree about eliminating the gauges. Is the alarm controlled by the
same sending unit as the gauge? If it is you could try swapping
sending units between the two engines to see if the problem moves.

If the alarm has it's own sending unit then the fact that the gauge
went to zero and the alarm went off suggests it really is an oil
pressure problem.

It can take a little bit for the lifters to leak down enough to cause
clacking but it is interesting that did not happen. Unfortunately
bearing damage starts almost immediately without oil pressure so
running it to see if the lifters leak down is not really a good idea.

Eisboch wrote:
"Eldon" wrote in message
oups.com...


You said the oil pressure went down to zero. Sounds kind of strange.
A friend in the marine business once told me that a problem like this
(one that occurs after the engine was worked on) is always related some
how to the last repair. I would guess they might have bumped the oil
pressure sending unit or its wire. Give the wire a look and see if its
a tight fit. Before I did anything major at this point, if the
sending unit and wire looks OK, I would replace the sending unit and/or
remove the sending unit and temporarily attach a mechanical guage to
the engine and get a real pressure reading. The reasoning behind this
if the face you said the enging sounded fine even after the pressure
went down to zero.

Regards, Bob


What he said.

Eisboch