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prostar205
07-12-2009, 12:22 PM
I need some advice. I have a '02 X-30 with the L-18 engine. I'm on vacation at my brother-in-laws lake place and the boat has been running great except when I filled the ballast it bogs down and could not get it past 15 mph. I has 1,500 lbs in the rear and 500 lbs in the ski locker. As soon as I moved more people in the bow, the boat picked up speed. I would think that with an L-18 it should really where the water is placed. Thoughts? I only had 4 people in the boat.

JimN
07-12-2009, 01:00 PM
I need some advice. I have a '02 X-30 with the L-18 engine. I'm on vacation at my brother-in-laws lake place and the boat has been running great except when I filled the ballast it bogs down and could not get it past 15 mph. I has 1,500 lbs in the rear and 500 lbs in the ski locker. As soon as I moved more people in the bow, the boat picked up speed. I would think that with an L-18 it should really where the water is placed. Thoughts? I only had 4 people in the boat.

How much gas in the tank? Check the fuel pressure.

prostar205
07-12-2009, 01:09 PM
Gas was half full. I'm thinking that I had too much weight in the rear areas (1,500 lbs) and only 500 lbs in the front. The boat runs great when I moved people to the front. The prop is a 13.5 x 17 OJ XMP CNC'd prop.

JimN
07-12-2009, 01:19 PM
Gas was half full. I'm thinking that I had too much weight in the rear areas (1,500 lbs) and only 500 lbs in the front. The boat runs great when I moved people to the front. The prop is a 13.5 x 17 OJ XMP CNC'd prop.

The weight shouldn't matter but the attitude of the boat can. If the bow was too high, the gas will seek its own level and if that includes not being where the fuel is taken by the pump, it can't be helped. In addition, the gas will slosh backward during acceleration and depending on where the pump is placed, that may cause more supply problems.

cbryan70
07-12-2009, 01:19 PM
you up high? With that motor one would hope nothing could stop it....

prostar205
07-12-2009, 01:27 PM
The pickup for the gas is in the near so I don't think it was a fuel starvation issue. The lake we're at is only 500 ft above sea level.

davomaddo
07-12-2009, 02:13 PM
are the rpms up where they should be?
if so, the engine is doing its job and it is a weight balance, trim tab, prop issue.
at
if you have a trim tab, put it 100% down to get up to speed - then adjust it up to your preffered riding level once you are at friding speed.

prostar205
07-12-2009, 02:16 PM
are the rpms up where they should be?
if so, the engine is doing its job and it is a weight balance, trim tab, prop issue.
at
if you have a trim tab, put it 100% down to get up to speed - then adjust it up to your preffered riding level once you are at friding speed.

Good point on the RPM issue. When it was bogging down, the RPMs wouldn't get any higher that 3,000 even at full throttle. I don't have a trim tab - the boat is a 2002.

JimN
07-12-2009, 02:29 PM
I would recommend taking it out under the same circumstances (exactly) and hook it up for diagnostics. First, check the fuel pressure. With a diagnostic computer connected, vacuum can be checked through the MAP sensor, throttle position, timing, RPM, etc should be watched through the range of use. If you have a timing light, look at the advance at idle and at higher RPM. If you aren't getting about 30 of additional advance at high RPM, check the knock sensor(s). If that's picking up knock, it's probably running lean. Why, is up to the actual problem. Also, make sure the knock sensor wire is connected.

davomaddo
07-12-2009, 03:51 PM
Bummer - sounds like a mechanical issue - much more difficult to deal with than weighting / trim issues.
Good luck. JimN has some good suggestions.