Twin 4.3's in 280 Sea Ray SunDancer

[dnsellers]

I have just purchased a 1989 Sea Ray SunDancer that according to my marine mechanic is a hair under 32 ft LOA. It currently has twin 4.3's, one seized completely and one still running, but with some hours on it. I made the decision to go ahead and replace both at the same time, despite the fact it still has one running engine (do you think thats a good idea??) Either way, my question is this. The new Vortec 4.3's I'm going to replace them with are approx 230 HP a piece (4 bbl). Although this size boat came factory with these little engines, and they claim cruising speed is approx 30 with top speed around 37, should I go ahead and upgrade to twin 5.7's? I can get them for around the same price, but according to the specs on this boat, fuel consumption will double and speeds wont chage much (w/ 5.7's, cruise was around 34 and top speed around 42) Anyone w/ any exp. w/ these engines in this size boat please advise. I would prefer keeping the smaller ones for the lower gas consuption, and if the numbers are correct, a 30 mph cruising speed is plenty fast for me. Thanks in advace for any opinions/advise. This is my first post by the way and this site is awesome. THANKS!!

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

By the way, it has a 4.5kw Onan gen, Satalite TV, radar, brand new GPS, central heat/AC both dockside and deployed, interior in near FLAWLESS condition, all upholstry outside brand new, hull in great condition, 6 gal water heater, inverter, 2-burner stove, microwave, fridge, and a 2002 tri-axle LoadRite trailer with flushdown and hydrolic brake system, full canvas and bimini top. I paid 13K from a desperite gentleman. Was this an okay deal?? Thanks again!!

 

[bomar76]

Re: Twin 4.3's in 280 Sea Ray SunDancer

First...welcome to the forum!<br /><br />Now...one problem you completely overlook in a swap to 5.7's is the drive ratio will be wrong. You would have to regear (not a good idea) or sell the drives and buy the correct ratio units.<br />You can sometimes correct this by going to a wacky pitched prop(s), but not always.<br /><br />While I am a big fan of more power....in this case I'd stick with the 4.3's. I'd replace both and sell the running take out on ebay or whatever.

 

[JasonB]

Re: Twin 4.3's in 280 Sea Ray SunDancer

You would also need to re-gear the outdrive most likely of you go from 4.3 to 5.7.

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

But are the 4.3's anough power in a 9000 pound monster?

 

[TilliamWe]

Re: Twin 4.3's in 280 Sea Ray SunDancer

Originally posted by Derek Sellers:<br /> But are the 4.3's anough power in a 9000 pound monster?

Were the ones that are in the boat right now? <br /><br />They wouldn't be my first choice of power, but since the boat is already set up to accept twin 4.3 v-6's, that what I would replace them with. It will be simplier & a better swap overall to go with the "new" Vortec 4.3's. Good luck

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

Thakns for everyones quick replies... Unfortunatly I have no idea if the ones in it were enough power, as I bought it broke Evidently Sea Ray thought it was an okay match up, as they were the ones offering it originally. Would you all say 13,000 was an alright deal despite immediate engine replacement, which I have already priced out at 5500 for everything (both engines) installed.

 

[rodbolt]

Re: Twin 4.3's in 280 Sea Ray SunDancer

you will find that 4.3's in that dinosaur are going to have to twist their max to push it.<br /> 5.7's at a minimum. its only money and you will like the extra pulling power.<br />I deal with seveal rinker's.searays and bayliners with the 4.3 and 5.7 with gensets airconditioning and the rest of the creature comforts. the last was a 32 bayliner that wiped 2 sets of 5.7's with bravoII drives so we repowered with 7.4's and bravoIII. now it crusies faster with slighly less fuel consumption but with plenty of power to spare.

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

LOL . I know it's only money, but I'm only 24 years old and trying to buy myself and my fiance our second home. I own an 18' Capri and another 25' Sea Ray, and really wasn't in a postion to purchase this boat, but everyone I spoke with told me I'd be a fool for passing it up for it's value. I know with everything said it should be obvious for me...go the cheaper route. Keep the 4.3's..better gas consumption and less expensive motor swap. But I am also the type of person who believes in doing it correctly the first time, despite cost. Hey rodbolt, can I borrow some dough??? Just kiddin. Anyways, thanks again guys, I have some decision making to do!!

 

[Don S]

Re: Twin 4.3's in 280 Sea Ray SunDancer

Do you have Mercruisers in it? Volvo, maybe OMC. I have no idea, but I do know that 4.3's are going to be small for that boat, plus 13K is a bit much for a boat that doesn't run. BUT!!!!!<br />Gear ratio's in drives can be changed, and if you really like the boat and aren't planning on getting rid of it in the next 10 years, then go with a 5.7 and get the proper gear ratio in the drives right to start with. Like rodbolt pointed out, the bigger engine with less throttle (read less fuel) will give you the same speed as the poor little ole 4.3's.<br />If you plan on running in salt water or brackish water, also consider a fresh water cooling system (closed cooling).<br />Your question about rather the 4.3L engines are enough to power the boat would be a definate "Yes, But". As long as you don't put a lot of personal stuff like food, water, coolers, friends, big generators, fishing equipment, cloths, toys, TV's and any other good stuff you could imagine taking on vactions and long weekends, then yes the 4.3's will be fine.<br /><br />PS: Posted this before I read your last reply.

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

True. I was in the same mind frame when considering 13k for a boat running 50%, if that. But looking at the resale value of this particular model, and the cheapest I'm seeing them go for is around 22k, and thats with well used engines and no where near the options. They seemed to average about 28 to 32k, and thats w/o the Genset and several other additions mine has. Now I'm second guessing my "investment" ( I know, oxymoron, right?) hahahaa. Anyways, in this case, I'm thinking repowering with the 4.3's will be the best case for my particular situation. I plan on keeping this boat at least for the next season, and I hope it will grow on me. But if not, I should have WELL less invested than I could unload it for. As far as closed cooling, that is definatly going to happen. After swapping the enigines I am selling the '02 trailer and installing the cooling system and it will be permanently stored in the water. Its just too much to be trailered. Thanks for reassuring me of that idea Don. By the way, they are Mercs. CHEERS!!

 

[tommays]

Re: Twin 4.3's in 280 Sea Ray SunDancer

Derek<br />i dont no how much you have had the hull checked but before going futher i would recomend that it be carefully inspected <br /><br />searay is much better at makeing wood look protected than really doing it right and many of there boats that age have hidden rot problems<br /><br />tommays

 

[crazy charlie]

Re: Twin 4.3's in 280 Sea Ray SunDancer

Derek,the price sounds good to me.Hopefully the drives and bellhousings(bellows etc.) check out ok.I own a Regal which is about the same size and weighs a little more than the Searay.I have twin 5.0 mercr with alphas.Plenty of power with 2 aboard.I surely think the 4.3s would be pushing it with more than 2 aboard and some gear.I would research the expense including alterations of the drives for the v8s.It may be worth it and will certainly make it more saleable when you sell it.The gas usage difference will be minimal.A hard working 4.3 may actually use more gas than a v8 .Charlie

 

[dnsellers]

Re: Twin 4.3's in 280 Sea Ray SunDancer

That makes perfect sense. I am having a survey done for insurance purposes and they said they will be checking the hull for density and rot. I am assuming by upgrading the motors they will have to install new engine mounts and everything. Also I plan on selling the trailer and leaving it in the water with a fresh water cooled system instaled w/ the engines, ubt one person advised against any I/O boat being left in the water. <br /><br />So many options, so little money. Oh well<br /><br />What additional expenses would there be by going the 5.7 route. I know the price of the engine is the same for both the 4.3 and 5.7 through my distributor, which is 1325 w/ heads, intake manifold, oil pan, timing chain cover, oil pump....basically everything except the carbs and risers/exhaust manifolds. Although the carbs on the 4.3's now look recently rebuilt, and are 4bbl Rochesters, they probably won't work??? I would have to regear the drives, and new mount configuration in the engine compartment. What am I forgetting???