GT-40 EFI Engine sputtering, ECM relay or FCC???

So this might just be an issue with the safety tether?

Bakchose, I don't think that we are talking about the same thing. I am talking about the safety lanyard switch that may be faulty. If there is a bad contact and the switch activates for half a second, the fuel pump will shut off for half a second and therefore explains the sputtering.

wetskier2000, you can come and ski anytime here but I can't say it's really warm! 55 air and 50 water.
I think the fuel smell occurs only once when the switch may have come off and back on a few time in a row,

I have the replacement hose anyway which I will replace when I change my fuel filter.

I will replace the safety lanyard and see if the problem reoccurs.

I am working on the manifolds right now. replacing gaskets and will have to gauge whether I can reuse the manifolds and risers for a few more years.

I am going to have bad dreams about safety lanyards and dams now :-)

To be more specific it was the low presure fuel pump. See my thread in Engine repair GT-40 injector breaker tripping. Last post was 8/13/12. I want to say the pump was $130.00 - $135.00.

The boat didn't start after running fine for a set. I noticed I couldn't hear the fuel pump anymore when turning the key. After checking a few things, I tried to play with the emergency circuit cut off switch and the fuel pump started again and the engine ran fine. I guess it could explain the whole intermittent cut of.

Hopefully this is it! The CEL only came on during engine off key on. However when the problem occurred it almost stalled the engine which I guess reproduce key on engine off for a second.

Anyway I will run the boat on sunday and see if it's a definitive fix.

Now I am worried about changing the riser gaskets and finding a decomposing manifold. The boat was only ever on fresh water, so hopefully it should be okay.

ok so I took the boat out today.

still waiting for my service parts that include the fuel filter with o ring and fuel pump hose.

Anyway I went out and tried to read an error code with my code reader but couldn't get it to work.

I decided to change my ECM and FUEL PUMP relays as this came up as a common fix and the boat worked fine all day. The issue never occurred.

I don't think I feel this is a definite fix but it's looking good so far.

Only problem is while we were running the boat without the engine cover, we noticed that the manifold were leaking a bit... starting new thread!

Yes I just ordered my service parts but it shipped already.

I think the hose is part number R035098B and costs $4

I will see if I can find it locally, so I don't have to wait!

Thanks Lewy2001!

Fuel filter and the small hose in there cracking? (Theres a fix kit for it) I had similar symptoms on my 1997 GT-40 and this seemed to be the permanent fix.

The CEL came on but I think it's more because the engine stalled. The light is on whenever the key is turn with engine off.

Lewy2001 if you have the pics of where the oil switches are, that would be great!

I will plug a fault reader next time as well.

Hi

I took the boat out for a test drive, unfortunately the fuel pressure gauge I had didn't fit. I will have to get one for a smaller valve. Anyone know what gauge fits? Is it just ford?

The service manual I have downloaded from Planet Nautique is for the old GT40 with high pressure pump at the back.

Anyway, I ran the boat (temp 45). Started perfect with a bit of a loping at idle which is normally only in the summer.

I ran a few passes including WOT over 40mph and everything ran fine. Water temp and oil pressure looked perfect.

I let the boat rest for an hour and ran another few passes in the course at 34mph. 1st pass fine, second pass the GT40 sputtered at the end of the course, I put the throttle in neutral and the engine stalled. Again water temp was on 150 and oil pressure steady just above 40.

I started the engine and cruised back to the dock at 30mph with engine sounding fine.

I checked the oil pressure switch and connections and it seemed fine.

I always leave the tank full and use the boat at least every other week. I will try dry gas anyway.

I will replace the fuel filter next week end, but someone mentioned a clear hose that could be cracked in the FCC, do you have a part number?

I will also get the relays R130011 at NAPA. Are they exactly the same as NAPA AR174?

Thanks for your help again!

Anyone knows where the high pressure pump is?

+1 on what Lewy said.

I told to a boat mechanic and he told that what I am describing is likely fuel related. Maybe a fuel pump about to die. I ordered an ECM Relay anyway and will try that as inexpensive enough.

cold manifolds is not a problem