1997 SN GT-40 Stalling - need advice

[TimS]

never did find time this past weekend to reinstall. When my boat has its problem, it's a slow stall/bogging as it starves for fuel. It isn't an instant stall like I assume a faulty breaker would present. When you boat stalled, was it gradual or was it like the key was turned off?

[Lewy2001]

If you have not changed the small piece of hose inside FCC it could be that. Change the filter while you are in there if it has not been changed recently.

[lucky7t]

I'm assuming this is a small block ford ?

I would change the ignition module on the front of the distributor. This module does alot. And are notorious for issues.

I build ford engines and these are bad right out of the box sometimes. I've found that napa gold usually are the best.

Hope this helps. You might check and replace the pickup as well.

[TimS]

Hey Lucky7t, thanks for the feedback. Replaced the stator and still having issues. It is a small block ford. A friend stopped by on Saturday and mentioned the same thing....the ignition module. That looks like the next step.

[Lewy2001]

I'm assuming this is a small block ford ?

I would change the ignition module on the front of the distributor. This module does alot. And are notorious for issues.

I build ford engines and these are bad right out of the box sometimes. I've found that napa gold usually are the best.

Hope this helps. You might check and replace the pickup as well.

PCM used a remote mount TFI ignition module not the distributor mount. You need to get the correct module as well as there are basically two types. One where the module controls dwell (push start) and the other where the ECM controls the dwell (CCD).

These should be the correct part numbers for the GT40 TFI
Remote Mount Black CCD "Computer Controlled Dwell" ICM

Motorcraft - DY1077 (supercedes DY679, DY667, DY645)
Ford - 5U2Z-12A297-D (supercedes F1PZ-12A297-A)
Wells - F139
Niehoff - FF413
BWD - CBE40
Standard - LX-241
NapaEchlin - TP29
Delphi - DS10056
Transpo - FM544


Not sure if this is your problem but it will not hurt to have a spare ICM.

Check out this thread on CCFan. Which has some great info on GT40 diagnosis.
http://www.correctcraftfan.com/forum...gt40-diagnosis

[TimS]

finally got to work on the boat. Replaced both relays, coil and ignition control module. ASV is fine and tank vent is clear. Problem repeated. Ran great for 1/2 hour, put it on the dock for an hour or two and went back out. Stalled from lack of fuel. Checked fuel pressure and found zero but I could hear pump activating (not sure which one) and they had power. Waited approx 10 minutes and boat started with proper fuel pressure. I've read some other posts on other forums and find the kill switch shuts the fuel pump(s) off. Didn't have the right tools to take the fuel cell off but opened the valve and very little fuel came out. Seems it will start after heating up but stalls once the fuel in the cell is gone. But wait 10 minutes and boat will start and run fine and problem will not repeat.....unless I shut it off again for a period of time and then problem will repeat again. My mechanic is stumped. Any thoughts?

[DanielC]

Here is a picture of the inside of the low pressure fuel pump.

Notice there are four vanes, and the only thing that makes then move out is centrifugal force, from the spinning pump rotor. They can get gummed up, or possibly have a small piece of dirt hold them in the center of the rotor, and they will not move fuel.

This is a picture of the main parts inside the pump.

At the top of the picture, is a screen. It collects dirt, and can stop the fuel flow. it just slips into place, and can be removed and cleaned. the parts go on the fuel pump in order, from top to bottom. Screen, metal disk, gasket, cover plate.

This is the pump, with the screen installed.


Then the metal disk.


A gasket.


And the top plate of the pump. Sorry, no picture.

See post #8, in this thread about low pressure pump pressure, and flow. The flow is more important number.
http://www.planetnautique.com/vb3/sh...=fuel+pressure

[east tx skier]

Did you replace the ASV or just push on the valve? Once they get gummed up, they are kind of damaged goods. My boat would do just what yours is doing. And would run fine for a while until the fuel in the canister was gone, at which point, it couldn't keep up.

[Up North]

I am not sure if you read my recent post, and what I found on my 97 Nautique, but I had similar problems, and ended up finding a problem with how the 90 degree tank fitting was not sealed with the pickup tube.

I would recommend purchasing some clear plastic tubing and run lines across the floor (to and from tank) to see if you are getting air

See http://www.planetnautique.com/vb3/sh...-to-20-Minutes

[TimS]

been working on the problem but I'm a weekend warrior and the boat is an hour away. Repeated the problem last Saturday. Opened the drain on the fuel cell and got only a few ounces of fuel. Spoke with my mechanic and he felt it was the low pressure fuel pump which he replaced 3 summers ago. He said I would be the third this year with identical issues and where the pump is cycling but not pumping fuel. Installed the pump this past Saturday and ran it without issues both Saturday and Sunday. Tried to repeat the problem but couldn't. I think it's fixed...finally. Bottom line is I got one year out of the pump before it started acting up as I've been dealing with the problem since July 2012....although it has become progressively worse. Thanks to everyone with all of the great suggestions and advice.