I have a 1985 Evinrude 175 hp outboard mounted on a 20' Grady White
Overnighter. I am having a problem with fuel delivery to the engine, let me
explain. The engine starts great and will run wide open at 4500 RPM for
about twenty-thirty minutes then it will bog down to 1500 RPM and I have to
leave it there or idling for a few minutes in order to continue. When the
engine bogs down I've noticed that my primer bulb goes completely flat,
sucked in on itself. When I let the engine idle the primer bulb slowly
fills with gasoline and becomes hard again. I can then put the engine back
at 4500 RPM again but this time I can only get five minutes before it bogs
down again, fuel starved. When the engine bogs down if I squeeze the bulb
frantically (It's still flat with just a little air in it) I can get fuel
through the line and get the engine to perform at a higher RPM, but I can't
squeeze fast enough to get it up to 4500 RPM. Again, if I put the engine in
idle, the vacuum in the bulb will slowly dissipate and it will return to its
bulb shape with fuel in it. My fuel mix is 50:1, I have new fuel, a new
water seperator, and a new clean fuel filter. I've disconnected the
anti-siphon valve on the fuel line, and I've checked and cleaned the fuel
vent and line. The primer bulb is installed in the correct orientation with
the arrow towards the engine. I do not know how old the primer bulb is as I
purchased the boat and motor this past spring. I have a spare engine and I
replaced the fuel pump on my engine with the pump from the spare. (Two fuel
pumps, same old problem). Does anyone have any idea what I should check
next? Can an old primer bulb cause these problems at high RPM's but not at
low RPMS? Could both fuel pumps be bad? Does a bad fuel pump deliver fuel
for twenty minutes and then malfunction, only to function again after
operating at a slower rate? Could the screen on the sender unit get clogged
and then unclogged given the parameters above? Could this be a carburator
or choke problem, are my floats sticking? The engine has been doing this
all summer, it's driving me nuts. When its running, it runs great, lots of
power, but then this fuel problem happens, over and over. There are fish
out there, any suggestions or ideas are appreciated immensely. Thanks

I'd work outside the motor. Replace the entire fuel line and primer ball
with one of at least equal inside diamater and quality. If that fails you
gotta look to the tank, sender, check valve, screens etc.

I doubt it's inside the outboard from what you're telling me.

-W

"Russell Hermansen" wrote in message
et...
I have a 1985 Evinrude 175 hp outboard mounted on a 20' Grady White
Overnighter. I am having a problem with fuel delivery to the engine, let
me
explain. The engine starts great and will run wide open at 4500 RPM for
about twenty-thirty minutes then it will bog down to 1500 RPM and I have
to
leave it there or idling for a few minutes in order to continue. When the
engine bogs down I've noticed that my primer bulb goes completely flat,
sucked in on itself. When I let the engine idle the primer bulb slowly
fills with gasoline and becomes hard again. I can then put the engine
back
at 4500 RPM again but this time I can only get five minutes before it bogs
down again, fuel starved. When the engine bogs down if I squeeze the bulb
frantically (It's still flat with just a little air in it) I can get fuel
through the line and get the engine to perform at a higher RPM, but I
can't
squeeze fast enough to get it up to 4500 RPM. Again, if I put the engine
in
idle, the vacuum in the bulb will slowly dissipate and it will return to
its
bulb shape with fuel in it. My fuel mix is 50:1, I have new fuel, a new
water seperator, and a new clean fuel filter. I've disconnected the
anti-siphon valve on the fuel line, and I've checked and cleaned the fuel
vent and line. The primer bulb is installed in the correct orientation
with
the arrow towards the engine. I do not know how old the primer bulb is as
I
purchased the boat and motor this past spring. I have a spare engine and
I
replaced the fuel pump on my engine with the pump from the spare. (Two
fuel
pumps, same old problem). Does anyone have any idea what I should check
next? Can an old primer bulb cause these problems at high RPM's but not
at
low RPMS? Could both fuel pumps be bad? Does a bad fuel pump deliver
fuel
for twenty minutes and then malfunction, only to function again after
operating at a slower rate? Could the screen on the sender unit get
clogged
and then unclogged given the parameters above? Could this be a carburator
or choke problem, are my floats sticking? The engine has been doing this
all summer, it's driving me nuts. When its running, it runs great, lots
of
power, but then this fuel problem happens, over and over. There are fish
out there, any suggestions or ideas are appreciated immensely. Thanks

What happens when you open the filler cap? This is fuel starvation from the
bulb to the tank or the tank itself (venting). If running with the filler open
suddenly fixed the problem I would look for a dirt daubber nest in the vent
cap. (BTDT got the T shirt)

He's right - I overlooked the obvious.

Start there - THEN do what I suggested - LOL

-W

"Gfretwell" wrote in message
...
What happens when you open the filler cap? This is fuel starvation from
the
bulb to the tank or the tank itself (venting). If running with the filler
open
suddenly fixed the problem I would look for a dirt daubber nest in the
vent
cap. (BTDT got the T shirt)

On Mon, 06 Oct 2003 01:58:46 GMT, "Russell Hermansen"
wrote:

I have a 1985 Evinrude 175 hp outboard mounted on a 20' Grady White
Overnighter. I am having a problem with fuel delivery to the engine, let me
explain. The engine starts great and will run wide open at 4500 RPM for
about twenty-thirty minutes then it will bog down to 1500 RPM and I have to
leave it there or idling for a few minutes in order to continue. When the
engine bogs down I've noticed that my primer bulb goes completely flat,
sucked in on itself. When I let the engine idle the primer bulb slowly
fills with gasoline and becomes hard again. I can then put the engine back
at 4500 RPM again but this time I can only get five minutes before it bogs
down again, fuel starved. When the engine bogs down if I squeeze the bulb
frantically (It's still flat with just a little air in it) I can get fuel
through the line and get the engine to perform at a higher RPM, but I can't
squeeze fast enough to get it up to 4500 RPM. Again, if I put the engine in
idle, the vacuum in the bulb will slowly dissipate and it will return to its
bulb shape with fuel in it. My fuel mix is 50:1, I have new fuel, a new
water seperator, and a new clean fuel filter. I've disconnected the
anti-siphon valve on the fuel line, and I've checked and cleaned the fuel
vent and line. The primer bulb is installed in the correct orientation with
the arrow towards the engine. I do not know how old the primer bulb is as I
purchased the boat and motor this past spring. I have a spare engine and I
replaced the fuel pump on my engine with the pump from the spare. (Two fuel
pumps, same old problem). Does anyone have any idea what I should check
next? Can an old primer bulb cause these problems at high RPM's but not at
low RPMS? Could both fuel pumps be bad? Does a bad fuel pump deliver fuel
for twenty minutes and then malfunction, only to function again after
operating at a slower rate? Could the screen on the sender unit get clogged
and then unclogged given the parameters above? Could this be a carburator
or choke problem, are my floats sticking? The engine has been doing this
all summer, it's driving me nuts. When its running, it runs great, lots of
power, but then this fuel problem happens, over and over. There are fish
out there, any suggestions or ideas are appreciated immensely. Thanks


If it's flattening the bulb, there is a restriction in the fuel tank,
or a fuel tank venting problem (creating a vacuum).

If you're using a portable tank, is the vent cap loose? If it's a
"built-in", I'd check the vent, and for crap in the tank that is
blocking the pickup tube.

Good luck,

....carry on.
noah

To email me, please remove the "FISH" from the net.

I'd almost bet on the tank vent, particularly with the long time frame to
the first time it fades.
I totally overlooked that on my 1st post. Too obvious LOL.

-W



"noah" wrote in message

If it's flattening the bulb, there is a restriction in the fuel tank,
or a fuel tank venting problem (creating a vacuum).

If you're using a portable tank, is the vent cap loose? If it's a
"built-in", I'd check the vent, and for crap in the tank that is
blocking the pickup tube.

Good luck,

...carry on.
noah

To email me, please remove the "FISH" from the net.

I've actually sucked a 6 gallon plastic tank flat - because I forgot to open
the vent.

-W

"Clams Canino" wrote in message
. net...
I'd almost bet on the tank vent, particularly with the long time frame to
the first time it fades.
I totally overlooked that on my 1st post. Too obvious LOL.

-W



"noah" wrote in message

If it's flattening the bulb, there is a restriction in the fuel tank,
or a fuel tank venting problem (creating a vacuum).

If you're using a portable tank, is the vent cap loose? If it's a
"built-in", I'd check the vent, and for crap in the tank that is
blocking the pickup tube.

Good luck,

...carry on.
noah

To email me, please remove the "FISH" from the net.

I've actually sucked a 6 gallon plastic tank flat -

When I was a kid, I knew a girl that could probably do that...... :-)

On Mon, 06 Oct 2003 03:01:40 GMT, "Clams Canino"
wrote:

I've actually sucked a 6 gallon plastic tank flat - because I forgot to open
the vent.

-W


You're not the only one. )

....carry on.
noah

To email me, please remove the "FISH" from the net.

Was her name Hoover by any chance?


"Gould 0738" wrote in message
...
I've actually sucked a 6 gallon plastic tank flat -

When I was a kid, I knew a girl that could probably do that...... :-)