Wont go over 15mph???

[joaquin12345]

So Ive been trying to get my new to me 1999 2100V Riders Edition Tige with the 350Mercruiser engine set up the way I want it.

One week ago I took my GF and her friend both around 120lbs. I weigh 180. Boat does not have ballast. At first, which was the first time taking the boat out since dewinterizing, the boat seemed to be hold back when I would push down the throttle. I could take off and it would pick up speed to about 20 but it took a long time. If I would have been wakeboarding I would have worn the person out. Anyways I figured just sat over winter. We parked and ate. Swam around for about 2hrs. Finally took it out and opened it up and everything was riding fine would pick up to about 35mph. Ended up pulling the girls on a tube and things were fine. Surfed a little while and it picked up speed fine. Was never impressed or felt it picked up good but I also went from an RZ4 monster to this boat so just figured it was just the age.

Well yesterday I went out and took 7 people including myself, a large cooler, full tank of gas. When we left the no wake zone I gave it gas. We sat at the docks with engine running approx. 20min waiting on my friend so engine was warm. The boat started to go but sure took a long time. Ended up picking up speed to about 20mph maybe. I let it run for a while across the lake thinking maybe engine was still cold. Ended up trying to wakeboard which was not a good idea. Got rider up but never went over 15mph tired him out quickly. Ended up surfing for a while which was fine. . Later on tried to pull a tube which was also a disaster. Could not go over 12-15mph so couldn't even swing the girls out if I tried. Had three people on the tube. Weighed about 120+120+150. Nothing crazy.

My question is what could it be?? Yesterday my rpms maintained around 2500 while goind 15-20mph. I can put it in neutral and engine sounds amazing. Revs up nicely up to about 6-7000. Last week would also rev up fine under load. Yesterday tho just seemed to not want to go.

Im attaching pics of what I have. Before I went out I did check my fluids. Engine was fine with oil and all that. Transmission on a cold engine showed to have the dipstick about half full, vdrive seemed fine. My question is do you guys think that maybe its my transmission being low on transmission fluid? Could that cause my boat to not go? I don't know what slipping actually feels like as mentioned in other topics but Im wondering if this is what going on. Let me know what you all think. Thanks. Also what kind of fluids do I need for my transmission and vdrive. Im attaching photos of the whole thing and the small plate is on the transmission. Motor Tige 1999.jpgtransmission label 1999 tige.jpg

[jslayde1]

I've had a similar issue with our old boat - ours would "bog" down when I tried to give it more throttle with a full boat. I didn't read where you mentioned that part though...

I believe mine ended up being an air issue. I changed the plugs, wires, and distribultor cap - but I believe cleaning the flame arrestor was the trick....

Might be worth a tune up if you haven't done so recently.

[boatwakes]

Propeller. You should have a 13.5X16 approximately. If you didn't hear the engine revving out and instead it just felt sluggish, your propeller is likely too large. Post what you see on the prop.

[ericinmich]

No, low trans fluid can't be the issue. The trans fluid is used by a pump to create pressure and press clutches together to engage forward or reverse. Low fluid would cause the boat to not move (much) as the clutches would spin and engine would rev.

Did you test drive the boat with similar loads and did it work OK? It almost sounds like the incorrect prop is installed (maybe changed to sell the boat). Too much pitch could cause what you describe.

Next steps would be a fuel issue IMO. I would start with adding sea foam to the fuel tank (proper ratio) and see if you get lucky and that fixes it. After that, an engine tune up and/or get the boat to a mechanic....