On Sat, 04 Dec 2004 05:14:35 GMT, "SamW" wrote:

It the electric fuel pump is down stream of the mechanical and
the mechanical pump has a blown diaphragm you could be pumping fuel directly
into the crankcase.

====================================

That sounds backwards to me unless we are using different terminology.

I think of downstream as being toward the engine and upstream as being
toward the tank.

The engine literally locked up when coming to a 'slow down' with the
boat. I tried to restart it and it acted like a low battery. The first
thing I thought of is: "ok we're overheated" but the temperature was way
under 150.

The engine had a pretty big jerk from the starter trying so hard. so I
knew it wasn't a low battery or bad starter. Sometimes I would get it
started and all of a sudden a lock up.
I had to be towed back to the boat ramp. This engine did not overheat. I
felt the manifolds and they wasn't barely even warm.

When I got home - I hooked up the ear muffs and it started right up. Ran
normal. It had me scratching my head.

I checked the oil and noticed it was about 2 quarts over the full mark.
It was not milky. So no water getting in the oil. I drained the oil and
it smelled like gas. I'm guessing gas is getting into the oil from the
Carb. So the engine lock up was from the crankcase being totally full of
oil (and gas in this case.)

When you come off plane and the backwash rams the rear of the boat there is
a possibility of water being rammed back into the engine and causing a
condition called hydrolock. I would think that that mostly happens with
thru-hull exhaust. I don't know if that is what you had, or why it went
away by itself on occasion.
The gas in the oil is possible not related to the lockup condition. If
there were gas being pumped into the manifold, I don't think it would allow
the engine to run, if there were enough of it to cause a hydrolock type
situation, and you imply that the engine was runnning when it happened "as
you were coming to a slowdown". Perhaps you could look into the carb before
and immediately after running the engine to see if the electric pump is
pumping extra fuel past the fuel bowl due to a float valve not completely
closing.
Check the side of the block to see if there is an old manual pump still in
the circuit.
I have a '95 4.3L with electric pump and a 4-bbl carb. On mine, the power
to the pump goes through an oil-pressure switch to prevent the pump from
filling the engine with gas when the engine is shut off. If your pump runs
before you start the engine, or continues to run after shutdown, then look
for that switch, and see if it's working(though that shouldn't cause any
problems on a "slowdown").
You might pull the plugs and look for any signs of water ingestion in the
cylinders by checking the condition of the plugs.

K. Smith:

Yes. Electric fuel in or near tank. There is also some other electric
pump in-line with the fuel line that runs at all times when the key is
on.

When I turn the key switch to the on position, you can hear the fuel
pump come on for about 4 seconds.

Thanks

JamesgangNC:

The fuel pump sounds like the one on my Chevy Silverado.
The tank is located in the middle of the boat under the floor. And it's
got a big "wheel" that you can turn and take off to see the top of the
tank, where the wires go into the tank for the sending unit.
It's a 2 barrel Carb (I think!)
It's got the choke on one side with two "holes" and the other side has 2
more. Maybe it's a 4 barrel?! Who knows!

Thanks,
Sonny

SamW:

I checked again just to make sure. The fuel line coming out of the Carb
goes directly to a fuel filter and then to the gas tank. No mechanical
pump on this rig.
Thanks,
Sonny

skinny32:

Thanks, I'll keep a note of that. I'll try that before I buy anything
for it.
And I better make sure I bring a backup motor when I test it out, just
incase !

Sonny

Floyd in Tampa:

The hydrolock sounds possible. But wouldn't the water in the cylinders
leak through the rings and cause a milky color to the oil?

I'm going to pull the plugs and see if and signs of water appear.
Thanks,

Sonny

Sonny H wrote:
K. Smith:

Yes. Electric fuel in or near tank. There is also some other electric
pump in-line with the fuel line that runs at all times when the key is
on.

When I turn the key switch to the on position, you can hear the fuel
pump come on for about 4 seconds.

Thanks


Ok thanks for that.

The electric pump running with "just" the key is unusual?? usually it's
setup so if the engine isn't "turning" the pump isn't running (mostly
they use the ignition pulses to sense) but;

if that's the case then there wasn't a time when the key got left on???
when the motor wasn't running??? It does sound like the fuel got in
while the engine wasn't actually running, the sudden lockup being a
consequence.

If you don't think that's the cause then it really does sound like the
float needle & seat. No big deal really.

Thanks for getting back.

K

"K. Smith" wrote in message
...
Sonny H wrote:
K. Smith:

Yes. Electric fuel in or near tank. There is also some other electric
pump in-line with the fuel line that runs at all times when the key is
on.

When I turn the key switch to the on position, you can hear the fuel
pump come on for about 4 seconds.

Thanks


Ok thanks for that.

The electric pump running with "just" the key is unusual?? usually it's
setup so if the engine isn't "turning" the pump isn't running (mostly
they use the ignition pulses to sense) but;

if that's the case then there wasn't a time when the key got left on???
when the motor wasn't running??? It does sound like the fuel got in
while the engine wasn't actually running, the sudden lockup being a
consequence.

If you don't think that's the cause then it really does sound like the
float needle & seat. No big deal really.

Thanks for getting back.

K

I don't know about the newer boat setups, but the last gas powered I/O with
an electric fuel pump that I had - ran the power to the fuel pump through an
oil pressure switch. The only time the fuel pump would run was if there was
sufficient oil pressure (either engine running, or, if bowl was dry, the
result of cranking over for a bit.

You don't want an electric fuel pump to run without the engine running.

Eisboch

On Sat, 4 Dec 2004 12:11:46 -0500, (Sonny H)
wrote:

The hydrolock sounds possible. But wouldn't the water in the cylinders
leak through the rings and cause a milky color to the oil?

===============================

That is generally true.