Mercruiser 4.3LX 205HP underpowered for 22 foot sea ray OV???

Jmac870

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The boat Im still looking at is an 1989 22 foot sea ray OV which is a fairly large boat. A friend of mine has a similar boat and its powered by a 5.7 L motor with 350HP... basically Im wondering is a 4.3 Litre V6 underpowered for a boat this large? I have 2 kids and the wife (plus all related gear that comes with them) so the boat will be heavy. opinins or advice would be appreciated. Thanks
 

alldodge

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The boat Im still looking at is an 1989 22 foot sea ray OV which is a fairly large boat. A friend of mine has a similar boat and its powered by a 5.7 L motor with 350HP... basically Im wondering is a 4.3 Litre V6 underpowered for a boat this large? I have 2 kids and the wife (plus all related gear that comes with them) so the boat will be heavy. opinins or advice would be appreciated. Thanks

You really want a V8 for this boat, the V6 if it has a bravo 3 drive will help but it really needs a V8
 

TexMonty

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Im not an expert, but have a similar size boat with a 260 HP Mercruiser. I would not want any smaller motor than what I have. It does pretty well and I don't have to be pushing it to cruise or pull tubes, but with 205HP on the same boat it would be well underpowered for any kind of water sports and even cruising long distances. I am sure others will chime in.
 

achris

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The boat Im still looking at is an 1989 22 foot sea ray OV which is a fairly large boat. A friend of mine has a similar boat and its powered by a 5.7 L motor with 350HP... basically Im wondering is a 4.3 Litre V6 underpowered for a boat this large? I have 2 kids and the wife (plus all related gear that comes with them) so the boat will be heavy. opinins or advice would be appreciated. Thanks

I replace a 230hp V8 in a 23' Caribbean with my old 1994 4.3LX a few years ago. The boat is 6 knots quicker (was 30 knots, now 36) and uses about 20% less fuel. The guy takes his wife and all their overnighting gear with them. It's also a very heavy boat.

As long as you don't overprop, that engine in that boat shouldn't be a problem.

Chris......
 

bruceb58

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I had a smaller boat with a 5.0 V8 and I was wishing I had the 5.7. No way I would have wanted the 4.3
 

Jmac870

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I replace a 230hp V8 in a 23' Caribbean with my old 1994 4.3LX a few years ago. The boat is 6 knots quicker (was 30 knots, now 36) and uses about 20% less fuel. The guy takes his wife and all their overnighting gear with them. It's also a very heavy boat.

As long as you don't overprop, that engine in that boat shouldn't be a problem.

Chris......

How does a guy know if the prop that comes on the boat is too much?
 

JaCrispy

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I just echo what TexMonty posted. I have a 22' with a 260 5.7 and wouldn't want anything smaller. If you don't need to cruise at 50mph I guess it would be ok. But I've seen worse, 21'ers with 4 bangers.
 

alldodge

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We have had many discussions on this topic and the variations between the V8 being needed for one 20+ hull, and the V6 does vary well for another 20+ hull, all comes down to the hull type. The Bertram style hull works great with the V6, but the Searay style hull needs a V8
 

thumpar

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The 4.3l would work but personally I like the extra power of the v8. No one says they wish they had less power in their boat.
 

Jmac870

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So while it may be enough to plane out, is it going to be overworking the motor on a regular basis ?
 

Jmac870

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Not to beat the dead horse as I already have lots of responses, but any chance anyone on here actually has a 22 foot sea ray with this motor in it?
 

achris

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How does a guy know if the prop that comes on the boat is too much?

Take it for a run. The engine should make the manufacturers maximum rev range at Wide Open Throttle.... For the 4bbl and EFI/MPI V6s, that's 4400 to 4800rpm... 2bbl V6s should make 4200 to 4600rpm... If it doesn't make those revs, the prop is too big (too much pitch)... If it runs a hundred or so revs over to top, all the better! :D ;)

Chris.........
 

bruceb58

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Not to beat the dead horse as I already have lots of responses, but any chance anyone on here actually has a 22 foot sea ray with this motor in it?
I am with Chris. Have the seller show you how it performs. Be aware that it will run different with more people onboard and full fuel tank and gear added.
 

Tail_Gunner

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The big question here is weight...so put four people in the boat and experience it. The 4.3 works well if there is not any weight in a boat any time you add weight it falls on its face so to speak. Torque is the real question here..horse power is close but the Torque rules the day, It is very possible that a demo ride with 2 people will yeild nice results but the first time you load a few people in the boat it will be dissapointing.. Or better said not the same boat you demoed.
 
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achris

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The big question here is weight...so put four people in the boat and experience it. The 4.3 works well if there is not any weight in a boat any time you add weight it falls on its face so to speak. Torque is the real question here..horse power is close but the Torque rules the day, It is very possible that a demo ride with 2 people will yeild nice results but the first time you load a few people in the boat it will be dissapointing.. Or better said not the same boat you demoed.

Any problems like that are taken care of by re-propping. The boat in my signature, is a HEAVY boat. That said, I've had 3 big people on, complete with our dive gear & 11 SCUBA tanks (yes, I counted them!) and all our gear for overnighting, and a full (180 litre/45 gallon) fuel tank plus 2 x 5 gallon spares and 2 x 5 gallon water cans. Engine didn't mind a bit. But that said, I am slightly under-propped. I pull about 200 rpm over the 4800 recommended... But rarely run at WOT (weather's just not that good most of the time)....

It's back to a test drive... Take it for a ride and see how it feels. Take a couple of friends along for the ride. Friends love coming out on boats... :facepalm:
 

bruceb58

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The boat/engine in your signature has an MPI and the OP's boat he is looking at is not. It is also 2' shorter than what he is looking at.
 
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achris

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The boat/engine in your signature has an MPI and the OP's boat he is looking at is not. It is also 2' shorter than what he is looking at.

The engine that was in the boat when I did that particular trip (30 nautical miles each way!) was the 4.3LX, not the MPI.... And as I stated earlier, that 4.3LX is now in a 23' Caribbean, and does just fine... For the same reason, propped correctly.
 

Tail_Gunner

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Any problems like that are taken care of by re-propping. The boat in my signature, is a HEAVY boat. That said, I've had 3 big people on, complete with our dive gear & 11 SCUBA tanks (yes, I counted them!) and all our gear for overnighting, and a full (180 litre/45 gallon) fuel tank plus 2 x 5 gallon spares and 2 x 5 gallon water cans. Engine didn't mind a bit. But that said, I am slightly under-propped. I pull about 200 rpm over the 4800 recommended... But rarely run at WOT (weather's just not that good most of the time)....

It's back to a test drive... Take it for a ride and see how it feels. Take a couple of friends along for the ride. Friends love coming out on boats... :facepalm:


Your point is well taken as your experience and expectation's show's in underpropping.. It is good to point out your under propped demostraighing your understanding and expectations to a good outcome. Not all boater's are savy to what to expect and how to remedy performance issue's and the result's....the very fact the OP is questioning the issue demostrate's reluctance or expectation's of the overall feel and i do mean feel hence the demo in a fully loaded boat. I two have a slightly modifyed 4.3 and absolutey love it speed... econ...and cruisng it win's the day with 3/4 people. Now 5/7 well that's another story in itself. It's a big 20' boat lots of capapcity and the minute that hull starts squatting with weight the boat totally loses it character..wetted surface area can be a real drag if you know what i mean..:lol:

As to under propping you know your speaking directly to the issue of Torque [h=1][/h]
 
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