I have a 2004 260da and since new could only achive 4600 wot. Also have trouble holding plane and have to run the boat up to 4000 rpms to maintain. Is anyone else having these problems. I bought this boat new and now have 60 hours on it hoping it would get better but its not.
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wot
- Thread starter krb260
- Start date
krb260,
Can you add some details ... motor type, OD, is this day to day use loaded or empty.
4600 doesn't sound that bad, really. What's your max listed RPM? 4000 to maintain plane does sound high. My uneducated guess would be 3000 - 3200 RPM woudl be cruising RPM. One might guess that your prop pitch is too low, but increasing that would decrease your WOT. Hmmm .... what are you carrying? What is the load out and balance like?
Can you add some details ... motor type, OD, is this day to day use loaded or empty.
4600 doesn't sound that bad, really. What's your max listed RPM? 4000 to maintain plane does sound high. My uneducated guess would be 3000 - 3200 RPM woudl be cruising RPM. One might guess that your prop pitch is too low, but increasing that would decrease your WOT. Hmmm .... what are you carrying? What is the load out and balance like?
- Joined
- Jan 1, 2000
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What kind of extra equipment are you carrying, how many people, is your fuel tank always full, how about water, waste, etc.
Having a single 350 on a 260 is a lot to ask of that motor for that boat. I had a Regal 2660 with twin 4.3 v6's and would not go smaller than a single big block on it even though you could. The small block bigger horse power requires a higher RPM. If you change your prop pitch so that you have more top and and get closer to 5K rpm your plain speed will be higher and take longer to get to but you will have a faster top end.
Having a single 350 on a 260 is a lot to ask of that motor for that boat. I had a Regal 2660 with twin 4.3 v6's and would not go smaller than a single big block on it even though you could. The small block bigger horse power requires a higher RPM. If you change your prop pitch so that you have more top and and get closer to 5K rpm your plain speed will be higher and take longer to get to but you will have a faster top end.
quote:
Originally posted by bob richards
If you change your prop pitch so that you have more top and and get closer to 5K rpm your plain speed will be higher and take longer to get to but you will have a faster top end.
Bob, I'm a little confused. krb does not mention speeds, only RPMs. If he re-props to get higher RPMs, I am assuming he will need a smaller pitch (lower gear). Although he will get the RPMs, he will still need high(er) RPMs to cruise and I don't think his speed will increase. If he goes with a longer pitch, he may shave some RPMs on the top end and may take longer to get on plane, but his cruise RPM may be less. Does that sound right? Or am I missing something?
Just what is the torque/HP of a 350 MAG compared to, say, a 7.4 MPI? We had the latter with a BIII on a 270SE and it was superb. Unless this is all normal (does Sea Ray have an opinion or spec sheet?), it is a head scratcher. The drive is not trimmed too far out, not carrying a lot of weight up front, trim tabs are up/down as needed.
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I have a 1999 270 Dancer wide body dry weight 7500 pounds with a 7.4 MPI 310 hp B3 drive.
3000 to stay on plane, 3500 cruise 4 people full tanks and stuff about 9000+ pounds loaded.
3000 to stay on plane, 3500 cruise 4 people full tanks and stuff about 9000+ pounds loaded.
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- Jan 1, 2000
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Scott,
In having actually two concerns in the original question, one being not getting to the expected RPM and the other being the fact that he needs to be at 4K to cruise are at opposite ends of the spectrum. That collective problem is because he is probably under powered. He can either use more trim tab, get bigger trim tabs to plain faster. To get the expected RPM's he needs to "grab" less water or decrease torque causing him to take more time to plain but giving him more high end speed.
In having actually two concerns in the original question, one being not getting to the expected RPM and the other being the fact that he needs to be at 4K to cruise are at opposite ends of the spectrum. That collective problem is because he is probably under powered. He can either use more trim tab, get bigger trim tabs to plain faster. To get the expected RPM's he needs to "grab" less water or decrease torque causing him to take more time to plain but giving him more high end speed.
thanks for the input . recapping its a 2004 350 mag multi port injection with 300 hp 2.20:1 with the smallest pitch props available (20p) on a bravoIII . 260 sundancer dry weight 7200 lbs it will plane but i constantly loose the bite it seems and have to keep rpms high often 4000. wot is 4600 fully loaded or empty. im an told by merc they want to see the rpms 4900 or 5000. i believe i need the new 2.43:1 ratio introduced in 2005 i believe but searay will not own up and tell me my warranty is up 60 hours on boat I just want to run at 25 mph and hold plane. it will run 28 mph wot **4600 anyone ever have this type problem
- Joined
- Apr 6, 2004
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krb,
I responded to your post in ATC, but I see you have posted here also. I don't thing that the problem is your gear ratio. I have an 04 260 w/350 MAG also. I do not have your problems even with full water, gas, and 3/4 holding tank. I have had 7 people on board - 4 adults and 3 children - and have the generator and a/c also. With 6 or more passengers I use the tabs to get on plane, but that is the exception, not the rule.
You are not getting the correct torque/hp from your engine. I had a similar problem a while back with a leaking exhaust manifold gasket.
I don't know where you boat. Are you burning gasoline or E10? I am not sure what the effect of ethanol is other than it has less energy than gasoline. Is the engine getting up to operating temp? Mine runs at 152 at the sensor. Does your engine run rough at idle when either warm or cold?
Do you keep it in the water, or is it stored on land?
Something is wrong and it is not related to the gear ratio.
I responded to your post in ATC, but I see you have posted here also. I don't thing that the problem is your gear ratio. I have an 04 260 w/350 MAG also. I do not have your problems even with full water, gas, and 3/4 holding tank. I have had 7 people on board - 4 adults and 3 children - and have the generator and a/c also. With 6 or more passengers I use the tabs to get on plane, but that is the exception, not the rule.
You are not getting the correct torque/hp from your engine. I had a similar problem a while back with a leaking exhaust manifold gasket.
I don't know where you boat. Are you burning gasoline or E10? I am not sure what the effect of ethanol is other than it has less energy than gasoline. Is the engine getting up to operating temp? Mine runs at 152 at the sensor. Does your engine run rough at idle when either warm or cold?
Do you keep it in the water, or is it stored on land?
Something is wrong and it is not related to the gear ratio.
If I cant reach wot, doesnt that usually require less pitch? 20pitch (which is what i have) are the smallest pitch available for bravoIII.
given this situation gear ratio is the only option,without modifing the props. I have 2.20:1 and think I should have 2.43:1. How do I get the manufacturer to step up on this matter.
given this situation gear ratio is the only option,without modifing the props. I have 2.20:1 and think I should have 2.43:1. How do I get the manufacturer to step up on this matter.
Sea Ray's prop chart is downloadable from their web site. According to their chart, with your boat and with that engine the correct OD ratio for a Bravo3 is 2:20 unless you operate at higher altitudes and then the ratio should be 2:43. The correct pitch is 20p in either case. They also state that you should be able to achieve 5000 RPM at WOT.
As long as you have no bottom growth, I think you have a legitimate complaint about your boats performance. If your dealer won't do anything about it, then call Sea Ray directly.
As long as you have no bottom growth, I think you have a legitimate complaint about your boats performance. If your dealer won't do anything about it, then call Sea Ray directly.
quote:
Originally posted by krb260
recapping its a 2004 350 mag multi port injection with 300 hp 2.20:1 with the smallest pitch props available (20p) on a bravoIII . 260 sundancer dry weight 7200 lbs it will plane but i constantly loose the bite it seems and have to keep rpms high often 4000. ........
Krb,
Just for reference, I have a 270 Sundancer with the 7.4, BIII and a dry weight of 6200lbs. My neighbor has the same identical boat with a 5.7 BII. Both non injected.
I can easily get on plane with any load and hold it on less than 3000. My neighbor struggles to get on plane and can't get on plane at all with a full tank and 4 or 5 people (about 1300# of people and gas, for a total of 7400#) Both boats and stored on a lift and have clean, unpainted bottoms.
So, you may just have too little engine if your dry weight is 7200.
Let us know how you solve this.
I just yesterday put the props back on and ran the boat with three people,3/4 fuel full water. I had factory mercruisier tech hooked up to engine. managed to get 4950 rpms full pork playing with everything. That is the most i have ever gotten out of her. maybe the prop shop balance or cleaning helped. However the boat wont hold plane at less than 3800-4000 in glass like conditions. Im now looking at trim tabs which are 11x11. bennett recomends one inch of tab for every foot of boat lenght. Im thinking my 260 da should haave 26 inches of 9 inch. 26x9=234. I have 11x11=121 sq inches definatley a big difference.
The trim tabs should be less of an issue once you get on plane. I think many with that boat retract the trim tabs after getting on plane. Until that last post, I was thinking maybe you have too much trim tab. If you have them fully down, that could slow you considerably. Do you have a GPS to give you your speed? Once you know you are getting speed out of your drive, then staying on plane becomes a hull issue, not an engine issue. That hull should get on plane by about 15 mph. You shouldn't have to maintain 25 to stay on plane. Try using the tabs to get on plane them raising them all the way. See what happens.
Many here have expressed interest in large block engines for this size boat. While it may be interesting for speed, it certainly isn't required to cruise easily on plane.
Many here have expressed interest in large block engines for this size boat. While it may be interesting for speed, it certainly isn't required to cruise easily on plane.
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- Apr 6, 2004
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krb,
Something ain't right here. I have the same boat/engine and have never had that problem. Mine might even be heavier than yours since I have a generator. I don't run at 3800 even with 4 adults and 3 kids on board, full water and fuel. I still cruise at 3650-3700 - I just burn more gas to do it. I can easily hold it on plane at 3500 rpms, and can ease it down to about 15-16 mph if I use the tabs and pay attention.
I keep mine out of the water, so it has a clean bottom.
Something ain't right here. I have the same boat/engine and have never had that problem. Mine might even be heavier than yours since I have a generator. I don't run at 3800 even with 4 adults and 3 kids on board, full water and fuel. I still cruise at 3650-3700 - I just burn more gas to do it. I can easily hold it on plane at 3500 rpms, and can ease it down to about 15-16 mph if I use the tabs and pay attention.
I keep mine out of the water, so it has a clean bottom.
One of our flotilla members had a '99 260DA with a 350/5.7 and B-3. Had a/c but no genset. Ran out well with 4POB, we could cruise on plane in the low-mid 3000s. It had the original trim tabs, was stored hi-dri, no bottom paint.
I'm asking him for information, but from my onboard experience with his, something's hokey with yours. What was the "cleaning" you mentioned earlier? You said it in connetion with "prop shop" but I think everybody here is looking at this assuming you have a clean unpainted bottom. If it's fouled, the boat will be a dog.
Given it's clean and you verified 4950 with MerC test equipment and the right props, I'd say the drive angle is wrong, boat hull is distored, or it's overloaded, maybe full of water someplace you haven't found.
I'm asking him for information, but from my onboard experience with his, something's hokey with yours. What was the "cleaning" you mentioned earlier? You said it in connetion with "prop shop" but I think everybody here is looking at this assuming you have a clean unpainted bottom. If it's fouled, the boat will be a dog.
Given it's clean and you verified 4950 with MerC test equipment and the right props, I'd say the drive angle is wrong, boat hull is distored, or it's overloaded, maybe full of water someplace you haven't found.
For the record I want all of you to know that I am a good friend of krb260. On friday we splashed his boat for a sea trial with an authorized Merc Rep. Hopefully I can give all of you another perspective without stepping on my buddys toes. As you might know his props were sent to a shop for analysis. Props were in spec but slightly out of balance. The shop balanced and "cleaned" them. Thats it nothing else. The only other variable that was different was the fact that there was no barnacle growth on the outdrive and trim tabs. Boat was cleaned very nicley last fall. I know this because I was the one who did the scraping. With the boat clean it ran at 4950rpm off his tach and the merc reps computer. We checked this at least three different times. All with the same results. The merc rep said the engine was running perfectly. During the acceleration test I felt the boat performed nicely. It jumped onto plane and had a max speed of 31 knots off gps. Keep in mind this was going upriver with the tide going out. You might want to add three or four knots for the relatively strong current in that area.
If this were my boat I would attribute the wot issue with barnacle growth. What concerned me the most was the way in which the boat needed to be operated in a safe manner. When the merc rep was slowing from wot to 3200rpm or wot to 3500rpm the boat had a very bow high attitude! Keep in mind that there were three very experienced boaters using trim and tabs to correct this issue. What we found was that the boat needed to be run at about 3800 to 4000rpm to run correctly at the stated load. Other conditions that might be worth noting outside air temp was 52 degrees very low humidity water was dead calm. With the summer heat and high humidity coupled with two to three footers this boat in my opinion would not be fun at all to operate.
The question that I would like to pose to all you experienced boaters on this forum is at what percentage of WOT should you be able to comfortably cruise at? I think 77 to 81 percent is to high (3800 to 4000/4950wot). What kind of engine life can he expect with those numbers? My boat a 2004 340 Sundancer runs great at 3200rpms (69%). I know it has twins but at least I am not burning up my engines to maintian a nice plane.
I hope that this post answers some of the questions that many of you might be thinking. Any further advice or opinions would be greatly appreciated.
If this were my boat I would attribute the wot issue with barnacle growth. What concerned me the most was the way in which the boat needed to be operated in a safe manner. When the merc rep was slowing from wot to 3200rpm or wot to 3500rpm the boat had a very bow high attitude! Keep in mind that there were three very experienced boaters using trim and tabs to correct this issue. What we found was that the boat needed to be run at about 3800 to 4000rpm to run correctly at the stated load. Other conditions that might be worth noting outside air temp was 52 degrees very low humidity water was dead calm. With the summer heat and high humidity coupled with two to three footers this boat in my opinion would not be fun at all to operate.
The question that I would like to pose to all you experienced boaters on this forum is at what percentage of WOT should you be able to comfortably cruise at? I think 77 to 81 percent is to high (3800 to 4000/4950wot). What kind of engine life can he expect with those numbers? My boat a 2004 340 Sundancer runs great at 3200rpms (69%). I know it has twins but at least I am not burning up my engines to maintian a nice plane.
I hope that this post answers some of the questions that many of you might be thinking. Any further advice or opinions would be greatly appreciated.