Help, I need a mechanic

[Wwunder]

I have a volvo 3.0 gs with an sx leg. Last weekend the engine died about 200 m from the tulista ramp after running from mayne island (about an hour). It felt like it ran out of gas, but i still had 3/8 of a tank. I subsequently checked my fuel sender, fuel pickup, filters, vent etc. and found no problems. after checking everything over I decided to take the boat out for another run to see if anything changed. It started fine at the dock and started to run out, and within 5 minutes it died. It would restart and as I tried to get up the speed it would quickly starve for fuel and die getting worse each time. Interesting I did detect a slight burning smell under acceleration during the past couple of runs. The fuel was fresh and I drained the filter and there was no water in it.

I had to come into the dock on the kicker both times. I was planning to head to the Salmon fest next weekend, but can't go unless the boat is up and running.

Can anyone recommend a mechanic in victoria? Any troubleshooting ideas? Could a bad manifold and riser cause this?

 

[Labman2]

My merc. 6 cyl., was doing that, carb rebuild cured it! Sounds like the jets.

 

[GDW]

Can you pump the fuel ball and get it back up to speed?

 

[Labman2]

Can you pump the fuel ball and get it back up to speed?

Shouldn't it have the basic mechanical fuel pump?
Then it doesn't have a bulb.
Mine exhibited all the same symptoms, idled fine, started as soon as you opened her up she calved!

 

[GLG]

Check your anti-siphon valve on your tank.

 

[GDW]

I had a similar sounding problem with my outboard which does have a fuel bulb that's why I asked. My problem turned out to be a fuel restriction inside the motor a little inline filter was stuck. When the motor died I could pump the bulb forcing fuel in and it would work again.... For about another 3 minutes then I had to pump the ball again.

 

[Wwunder]

Thanks for the input guys, I didn't even notice if there was an antisiphon valve when I was checking the intake (which isn't screened at all BTW). Would it be installed right at the elbow at the tank pickup? I will take a look at that tonight, but I'm thinking more along the lines of it being the carb.

There is no pump ball to the inboard, but the kicker fuel line is Tee'd off the main fuel line. I haven't had any problems getting the kicker running off of the main tank so, unless its a high flow vs. low flow issue it seems the pickup up to the tee should be ok.

 

[Labman2]

If you have good fuel supply to your kicker, it is definatley one of two problems.
Fuel pump/Filters or carb needs rebuild. In my case, it was the carb., the inside looked like someone puked in it!
I have a couple of boats with IOs and in floor fuel tanks, neither has an anti siphon, I would assume that is a funtion of the mechanical fuel pump.
Even if it were somehow returning to the tank, as soon as it starts pumping, there is positive pressure to the carb, it can't siphon back while it is running. IMO.

 

[Seafever]

Clogged fuel filters will do what is happening to you, Wwunder.

 

[Wwunder]

Thats what I was thinking... It died while running at cruise (3400 rpm) so it should have had plenty of suction. I still need to check the little filter at the carb inlet, but I also think it would be nice to check if the fuel pump is outputting properly. It seems a bit weird to me that the problem came on so suddenly. It was running great all weekend and after putting 60 miles on the boat in 3 days without a hint of a problem and now won't run at all.

 

[salmonkiller01]

I would change the main fuel filter first.

 

[Lipripper]

I had a wasp go up my vent and die in the tank. It would idle perfect all day till you bumped it up.. Then it would get sucked up in the pick up and starve the carb. A couple minutes later It would start just fine.
That wasp plagued the guy I bought the boat off of for a year (not sure why the gas didn't eat it, it preserved it) He dumped a bunch of money in to the thing and I found that in a few days. I got a good deal on a boat and we was pissed off


Also check your lines for cracks.. At that kind of RPM you'll be sucking air in

 

[GLG]

You could hook up a separate fuel tank and line to test your fuel system.

 

[triplenickel]

You could hook up a separate fuel tank and line to test your fuel system.

Yup with a little jerry can so you can play with gravity and figure out of it's a pump problem.

 

[Wwunder]

I'm hoping I found the issue. I had replaced the water separating filter can, but had neglected the sintered filter at the carb. I pulled it out last night and found a fair bit of corrosion and gunk on it. I couldn't even blow air through it. So I'm going to go buy a new one plus a spare and reinstall tonight. Wish me luck!

 

[Wwunder]

Well, I can confirm that the little sintered filter in the carb was the source of my problems. It has now been replaced and the engine ran beautifully tonight.

Thanks for help everyone.