Fuel Preasure issue

[svsparky22]

I have a 2000 20i, last weekend I was out and had been sitting for over 2 hours. I started the boat and when I went to take off it dies. I tried to start again and no fire. I took the cap off to check the fuel preasure and there was none. Each time I turned the key, I could hear the fuel pump kick on but still no fuel coming through. After being towed in 3 hours later I was messing with the boat and out of no where I had fuel preasure and the boat ran fine the rest of the day. Same issue I had last year but changed the fuel filter twice and seemed to fix. Any suggestions on what would cause this???

[whitlock87]

I have a check valve on my tank, maybe yours is sticking.

[svsparky22]

I checked the check valve and looked fine, also looked for an anti sipon valve but did not see it. I also checked the 3 fused on the motor and they looked fine.

[dogbert]

It could be your fuel pressure regulator, mine went bad a couple of years ago. It's a diaphragm that can disintegrate when you have ethanol in your fuel. Your fuel pressure regulator is located on the port (left) side of the engine.

[jsz]

Mine did the same thing to me several times before I found out it was the fuel pump. There has been a lot of talk about this lately. Do a search for "fuel pump" and you should get a bunch of info.

[TX2100V]

Fuel Pumps...

I replaced my fuel pump twice before I found the real culprit. I had a bad connector that would overheat from the increased resistance. I'm guessing it got hot enough to anneal the contact and it lost it's spring pressure to hold the contact surfaces together, thus accelerating the failure. Once I removed the connector and butt-spliced the wires together, the fuel pump has been problem free.

I just wish I had found the real problem the first time around!

Mike

[TRD]

I had this happen while we were surfing. Drained the sacs and boat still wouldn't fire. Remove the cap at the end of the fuel rail and press the needle (it looks like a tire valve, make sure you have a rag over the end). When the all the air was gone and gas came out the boat fired up and we haven't had a issue since.

[JUST-IN-TIME]

either you got

vapor-lock
clogged fel filters, threes 2 of them
fuel pmp going out


the fuel pressure reg has nothing to do with pressure out of pump, its the return it sends back to the tank it regulates

[boatwakes]

Just in time, the fuel pressure regulator on EFI engines has EVERYTHING to do with pressure out of the pump. A faulty regulator can cause pump pressure to go as high as 45psi if the regulator stays closed and never get above 15 if it's stuck open. The operating pressure should be at 30psi +or- 2 psi from that value and if it's not the first thing to check (per manual) is the regulator. Also, svsparky's boat does not have a fuel return to the tank. The unburned fuel gets returned back to the secondary fuel filter as well as the fuel returned from the regulator. You're a tech right?

[JUST-IN-TIME]

what im saying is that if the fuel preesure reg was faulty you would have high/low pressure
its based on return to the pump
if u had a clogged return line you would have bad fuel press
the fuel pump will still put out its recomeded press

[chpthril]

what im saying is that if the fuel preesure reg was faulty you would have high/low pressure
its based on return to the pump
if u had a clogged return line you would have bad fuel press
the fuel pump will still put out its recomeded press

Fuel pressure is always measured on the pump side, so it's impossible to have incorrect, your words were "bad" fuel pressure, while the pumps still puts out it's recommended pressure.

Next time you have a fuel pressure gauge hooked up and the engine running, pinch off the return line and note what the fuel pressure does. It's called dead-heading the pump. You will see that these pumps are capable of 2X or more PSI them what their normal operating range is. This is directly due to the fuel pressure REGULATOR. The regulator is a variable orifice controlled by engine vacuum (rail mounted ones). This regulated opening controls the amount of fuel allowed to return to the tank. The amount of fuel allowed to return to the tank itself is not important, but the amount allowed to pass bu the regulator directly effect the fuel pressure measured on the pump side, which happens to also be the injector side. If more fuel is allowed past the regulator, such as with the engine at idle or a steady speed and light load, pressure is at it's normal operating level. as engine vacuum drops, such as while under acceleration or heavy loads, the regulator closes off and allows the pump to build more pressure in the fuel rail.

So, in summery, the fuel pressure regulator has a lot to do with fuel pressure.

Regulator stuck closed or no vacuum, you will see the upper end of the operating range, about 45PSI

Regulator stuck open, you will see the fuel pressure stay around the normal range of about 35PSI.

If the regulator is plugged with debris, one would probably see excessively high pressure. Same with a kinked or collapsed return line.

Plugged filter or clogged or kinked feed line = low pressure accompanied by a high pitch whine from the pump as it's working its arse off.

Due to the typical design of a regulator, I doubt one could fail in a manner that would allow more fuel to pass by it then normal, so if one is diagnosing low fuel pressure, I would look up stream toward the tank. Kinked/collapsed line, plugged filter, bad pump, leak in the sending unit, plugged sock, low voltage at pump (could be on the + or - side), etc.

[illiniboarder88]

I had the same problem on my 20i. I replaced the fuel pump, and the problem was solved. If you hear the pump cycling on, it's not the connection. That's interesting that someone else has had problems with the conncection because I've had similar issues at times.

[M&M]

From M&M. I have a 2000 20ci. Twice last summer was boating and stopped to swim for couple hours. Boat would not start. Towed in to service dept., said nothing wrong, vapor lock. Use blower more to exhaust hot air. I guess I will find out if this works next July when it gets hot in MO.

[ospo]

I think the present problem most likely is due to faulty fuel filter. Another possibility is that there must be some dust in it. I would advise him to clean it. Most probably it will solve the issue. If still is having problems then he should replace it with a new one. He should regularly clean it to prevent such issues from occurring in the future.