Not getting Fuel on 2001 SunSport with 350 Indmar Assault

[winterbrau]

I am having an ongoing problem over the past couple of years with my 2001 Supra Launch Sunsport direct drive with the Indmar 350 Assault engine with EFI.

With no rhyme or reason the boat will randomly not get fuel in the middle of a boating session and not matter what I do will not start.

However, sometimes after letting it sit overnight it will start right up and run for days before doing this again.

If I poor gas down the throttle body it will start and run that gas off so I know spark, igintion, etc is working.

In the past I have replaced the fuel filter and it started right up. Another time I went through all the electrical connections, and it started right up. This time I have done both and can't seem to figure out what the problem is. I can hear the fuel pump charging when I turn the ignition key, but I'm not getting any fuel spray out of the injectors.

What are the possible problems that I might need to diagonse?

Anyone else having the same problems?

Thanks so much!

winterbrau
Dallas, TX

[86supraproject]

It sounds like your engine is throttle body injected. If you can hear the fuel pump run, I would pull the main fuel line where it enters the throttle body and see if the fuel is making it up there. This will only be effective if you check it when you are having the problem. If you are getting fuel then it could be either something after the fuel line is blocking the fuel or a pcm issue. The throttle body is 50/50 pcm/mechanical. The mechanical part just opens the butterflies.

[winterbrau]

thanks for your reply, I am having the problem right now so yes I plan to pull the fuel line as you suggested and replace the fuel filter again since they are inexpensive.

If I'm getting gas up the main fuel line to the throttle body (which yes I beleive is throttle body injected and the labels on the air cover say EFI) this is definately NOT the holly carb type (friend has one), think those ended one year earlier in 2000 models.

What do you mean by PCM problem? Also, the butterlies are opened mechanically via the throttle cable.

[86supraproject]

By pcm, Im talking about some sort of computer that will send a signal to the injector to tell them to start giving fuel to the engine. As new as your boat is I would say there is one hid somewhere.

[knoble]

You have an electric fuel pump on that. There should be a screen on the pickup or if it is an in tank pump. At the bottom of the pump is a screen/pick up. It a long shot but check to see if that is clogged up!

:cool:

[winterbrau]

Finally figured out the problem. All the fuel system worked by unplugging main fuel line from gas tank to low pressure fuel pump and connecting a 3' hose into a household gas can boat started up with no problem. Therefore the problem ended up being on the "anti-syphon valave" on the gas tank line itself. A $20 part along with a new fuel pick-up tube and I was back in business. What a pain find the right parts though b/c Supra uses different gas tank makers over the different years.

DON'T try you local new boat Supra or other dealers, waste of time, they don't carry these specialty parts. I ended up going to a reputibile Marina in Dallas and they had it in stock no problem.

Hope this helps!