cant get 2006 290 da on plane

[nra4ever]

I have only had this boat a few weeks and I cant always get it on plane.

I have twin 5.0 BIII with about 180 hours. the boat was salt water and now its fresh water. I am sure the BIII are all the way down according to the smart gauges and the needles on the dash. The boat is full of gas water gear u name it.

I have had the rpms up around 4500 before and the boat ran great for a bigger boat with 5 adults. I have trim tabs and have no clue how to get the best results and there does not seem to be an indicator on the dash as to the position of the tabs.

I had 4 adults a 12 and a 1 year old on yesterday and got on plane going out after a bit but not at all on the way back. the rpms would not go past about 3000 and there was a lot of water churning at the back of the boat but no get up and go. there was also a strong gas smell.

Any help would be greatly appreaciated.

 

[Lord Farringdon]

One thing you haven't mentioned is the condition of the hull. You say you have only had the boat a few weeks. Did you have it out of the water for survey and if so did you notice if the bottom was clean or covered in growth?

"The boat is full of gas water gear u name it."

You might also want to consider where you have all that gear stowed and reducing the amount you have on board. Too much gear stowed aft along with all your pasengers and a dirty hull and things may just be getting all too hard for the boat. When next you are in the marina, just get someone to observe the trim tabs while you play around with them and get used to which way brings them up and which way takes them down.


Your engines might also have a problem reaching rpm but if that is the case it might be because you are overpropped for the loads you intend carrying. The previous owner may have been light on gear and passengers and fitted props for maxium speed. If you are to operate on the heavy side you will need smaller pitched props which will get you out of the hole quicker but which will also reach wide open throttle (WOT) at a slower speed that currently. It's all a compromise.

So, make sure your hull is clean, distribute your gear evenly about the boat, trim tabs down some, move some of your passengers forward until you've climbed out of the hole and ensure you are propped correctly for your type of operation.


Terry

Good luck and congrats on your new purchase.

 

[nra4ever]

thanks terry.

The hull was squeaky clean when i got it! The boat has only been in the fresh water a few weeks.

I filled the boat up with gas and water when i got it. same amount of gear each week. I have used about a quarter tank of gas so the load is getting lighter and the performance is getting worse just does not make sense.

Got on plane going out and would not plane coming back.

Any idea what the factory pitch should be?

 

[Lord Farringdon]

According to the Parts Manual your props should be:

1427095 Prop, 15.5" x 24" Cup BR3 LH
(T-5.0L MPI BR 3 (T-260PHP) MCM Stern Drive

1427103 Prop, 14.25" x 24" Cup BR3 RH
(T-5.0L MPI BR 3 (T-260PHP) MCM Stern Drive

Have you checked your bilge? Not filling with water down there are we?

 

[pharmaboy]

never underestimate how much difference a few people on the back seat make.

i have a 300 with the same engines, and 2 200lb males on the back seat (or a fat woman, but I do discourage those) ;D and planing is a mightly long and difficult task , and if the tanks are full, no chance. put the heaviest people on the seat next to you, and on the seat facing backwards as well. Your center of gravity is just behind the helm I think, and your water, and fuel are equal with or behind that point.

 

[Good Grief]

take the boat out by yourself and see if you can get it on plane without trim tabs, then using the trim tabs to see the difference. run the boat full out and see what RPM/speed you can get too, be careful not to exceed the max RPM limit for your boat/motors. Since you were able to get on plane before you should not have any trouble but it will help establish baseline data to suggest changes from.

For me, it is easier to get on plane by easing the throttles up instead of pouring on the power from a slow cruise.

Let us know what you find.

 

[mainstream]

I just had that problem at 100 hrs on my 8.1 s turned out to be a fouled plug due to the fact my boat was a left over and sat for a while with out being run so when ingot it and started running it the engines just started not getting to wot rpms and a strong smell of unburnt fuel in my exaughst

 

[Cincy Aquaholic]

I have your exact boat and am pretty sure something is wrong. I highly doubt this is a weight issue. I've had heavy loads with 8 adults on mine and it does get on plane. Bad fuel? Fuel filters in the cool fuel modules clogged?

 

[Lazy Daze]

I agree that, while weight can play an issue, it doesn't seem to be the problem here. With twin V-8's and B3's, you should have no problems.

Checking plugs is a good idea. Clogged filters or bad fuel is another good thought. Do you use an anti-ethanol additive ALL the time?

I'd also be curious to know if the drives are physically going all the way down, not just according to the gauges. Also, is anything caught up in the props (or around the drives)?

Side note about tabs... Start with them all the way up (retracted) and have someone watch them while you fully deploy them - count the seconds it takes. Now you have a baseline. Don't be shy of using them - put them all the way down if you need to, then adjust as needed after you get on plane. They are an excellent "tool" that makes using the boat more enjoyable and more comfortable.... Doesn't do any good if you leave it in the tool box!

 

[nra4ever]

thanks for all the suggestions

I did lift the hatch to see if i had water and no water. shew i worry every week that when i get back to the marina they are doing to tell me it sank while i was gone. lol

I will take plugs with me when i go back and change them out. which plugs are the best and what is the gap?

I will add some fuel and four cans of sea foam incase its a problem with fuel.

anyone know where the filters are located? i can change those out as well.

I am going to ask one of the other boaters on the dock if they will drive it and see if they can get it on plane in case its a matter of user error.

 

[matt327]

I had the same problem a few weeks back and it turned out to be the distributor cap. Might want to check that also. Good luck.

 

[Cincy Aquaholic]

I don't believe there is a distributor cap.

For fuel filters search the forum. It's different than the typical oil filter style kind. It's a real pita. They will be on the starboard side of the motors behind the water pump in an enclosure.

 

[Lord Farringdon]

thanks for all the suggestions

I did lift the hatch to see if i had water and no water. shew i worry every week that when i get back to the marina they are doing to tell me it sank while i was gone. lol


I am going to ask one of the other boaters on the dock if they will drive it and see if they can get it on plane in case its a matter of user error.

Sorry to worry you like that. I didn't think you may have been some time and distance from the boat.:smt101

Getting another opinion is good but I'm sure I don't have to remind you to be careful about who you give the helm to. The last thing you need is some cowboy from the local marina club slamming the throttles up and down on your prize posession. Do you have a nearby Mercruiser dealer you can talk to? Maybe they can go for a run with you.


Terry

 

[Gunn]

I would still suspect a weight issue, personally. I've had my boat for nearly a year and didn't have any issues getting up on plane until I had some passengers that really added some weight. Th boat struggled as yours did, the RPM not climbing, but hovering around 3200rpm. I had them move closer towards me and then she planed right out.

I've since learned that in these situations, I fully lower my tabs (counting the time for your tabs to extend is a great tip that I use too), make sure the drives are full down and then go at it, slowing advancing the throttles. From 3200 to 3800 rpm still takes some time, but the RPM slowly increases constantly until we are on plane and I can back off the throttles, then begin raising the tabs, etc.

Try with full tabs down next time as see if there is a difference. And I would not let someone else at the helm...they won't know your boat as well as you already do.

Tom