Mercruiser 5.0 TKS vs 4.3 MPI

[Bhebert449]

I am looking at a 2009 Sea Ray 195 sport that has the 5.0 tks engine. This is a carbureted engine, correct? Many of the other used boats in this price range have the 4.3 MPI rated at the same HP.

Any concerns with a carbureted engine on this model? Should I opt for a fuel injected engine?

 

[Scott Danforth]

buy the 5 liter, upgrade it to a 4 barrel for about 240hp at the prop (270 at the crank)
however the boat will be a 48-50mph boat

 

[Bhebert449]

buy the 5 liter, upgrade it to a 4 barrel for about 240hp at the prop (270 at the crank)
however the boat will be a 48-50mph boat

how will the 5.0 perform in the sea ray 195. It is 20’ long and weighs around 2800 lbs I believe. Do you have to change the intake if you change the carb?

 

[louc]

Yes if it currently has a 2bbl carb you have to install a 4bbl manifold & carb.

 

[Scott Danforth]

The 5.0 will perform great. I had one in my 2002 SeaRay 190 which weighed 3000#. I would hit 49.5 mph with 2 people.

If I would have kept it, I was going to upgrade to a 4 barrel to hit low 50s

 

[mr 88]

You will have more torque with the 5.0 ,which is helpful when loading up the boat and or for skiing , better hole shot .

 

[QBhoy]

If you want turn key boating and no messing with carbs...get the 4.3 mpi. An outstanding engine and every bit as powerful pound for pound as the thirstier 5.0 carb. Can also use plug and play smart craft gear too. These are proven to push your average 18/19ft bowrider to 50 mph and sometimes slightly more, well propped.

 

[Scott06]

how will the 5.0 perform in the sea ray 195. It is 20’ long and weighs around 2800 lbs I believe. Do you have to change the intake if you change the carb?

I have a sea ray 200 sport with a 5.0 carbed. So that boat will do great with a 5.0 TKS. This is my second sea ray and both have held up really well.

I personally prefer the carb as I do all my own work and while I know I will have a few (2) carb rebuilds over the 15 years I plan to keep this boat, I can fix it with basic tools, or at very worse go buy a new one ( edlebrock 1409) for $450. The edlebrock has great throttle response vs the 2 bbl that is stock

Qbuoy is right a 4.3 mpi and a 5.0 TKS will probably be pretty close in performance. So if you prefer MPI don’t be afraid of a 4.3.
I really like the 5.0 for the flat torque curve. My typical use is 6-8 people and skiing or wake boarding so holeshot is great

 

[Bhebert449]

I assume the 4.3 will be better on fuel economy. Is it a significant difference? I plan to use the boat mostly for cruising and water sports.

 

[Scott06]

You won’t notice much difference. At the same hp out put they will use pretty much the same amount of fuel.

1. if you are concerned about fuel economy pick a different hobby.
2. fuel economy is determined by how hard you hit the throttle.

there are a couple gph fuel consumption calculators on line they will give u and idea how much fuel burn will be. https://www.boat-fuel-economy.com/mercury-mercruiser-3.0-181-fuel-consumption-us-gallons

my 5.0 is about 16-18 gph at WOT, my old 3.0 was about 11 Gph.

 

[mr 88]

The " fuel economy " is based on how heavy your throttle hand is. The - gas - difference between the 4.3 and 5.0 is minuscule. The 5.0 has more torque which means its going to get up on plane with less gas than the 4.3. Has more cylinders which means less wear and tear on the engine if your cruising at the same speed as a 4.3. The 5.0 will be better for water sports bc of the torque and will be able to keep a steadier speed for sports like wakeboarding. The biggest difference between a carb engine and EFI is in starting up. Now most EFI engines are newer so there is usually a few more refinements in the heads that may help your fuel economy. For the average 50 - 100 hour a year boaters that may translate to about 50.00. My guess is if you get 2.0 mpg at cruise with the 5.0 and the 4.3 is newer in design you might get 2.1 with that. 3,000 rpm is usually the sweet spot for optimum fuel burn. So you may be cruising at 27 mph with the 4.3 and 28-29 with the 5.0 at the same rpm. I have a couple 4 barrel 5.0s in one of my boats with 1300 hours on them, 150 lbs of compression across the board on the cylinders , pushing a 9,000 lb hull ,smooth as silk at idle and as easy as it gets maintaining them.. IMHO great engine as is the 350 which I have owned as well

 

[mr 88]

You won’t notice much difference. At the same hp out put they will use pretty much the same amount of fuel.

1. if you are concerned about fuel economy pick a different hobby.
2. fuel economy is determined by how hard you https://www.boat-fuel-economy.com/mercury-mercruiser-3.0-181-fuel-consumption-us-gallons

my 5.0 is about 16-18 gph at WOT, my old 3.0 was about 11 Gph.

The big difference in your fuel consumption numbers are probably bc of a few things unless they were in the exact same hull ,which I doubt. The 3.0 was probably in a smaller ,lighter hull than the 5.0 . The difference in drag and weight would make a huge difference. There is a formula that is pretty basic that you need X amount of fuel to produce Y amount of hp. So if you need 100 hp to keep your boat on a plane , regardless of a 5.0 or 4.3 for either of them to make 100 hp you are going to use the same amount of fuel. Providing everything else is equal as in the hull itself and weight in the boat..

 

[Scott06]

The big difference in your fuel consumption numbers are probably bc of a few things unless they were in the exact same hull ,which I doubt. The 3.0 was probably in a smaller ,lighter hull than the 5.0 . The difference in drag and weight would make a huge difference. There is a formula that is pretty basic that you need X amount of fuel to produce Y amount of hp. So if you need 100 hp to keep your boat on a plane , regardless of a 5.0 or 4.3 for either of them to make 100 hp you are going to use the same amount of fuel. Providing everything else is equal as in the hull itself and weight in the boat..

Absolutely I just gave that for engine comparison. 3.0 was in a 17 ft the 5.0was in a 21 ft. But to your point the 3.0 will only use enough fuel to make 135 hp not the 260 that the 5.0 makes, so It’s really about how much hp you are making and using at a given throttle position ...

again fuel economy is a misnomer in a boat , you will use 1/2 to3/4 of the wot gph for general use. I figure about 10-12 gph for my typical use of cruise and ski

 

[JimS123]

I personally prefer the carb as I do all my own work and while I know I will have a few (2) carb rebuilds over the 15 years I plan to keep this boat

We sold our 3.0 Mercruiser last year after having owned it for 35 years. About 1250 hours on the clock. Maintenance was by the book and we used E10 for however many years it was available. The carb was adjusted as necessary and I replaced the choke spring once, but the carb was never rebuilt. The motor ran like a top and my annual performance curve was unchanged since 1984.

Was my boat an anomaly, or did the ethanol have something to do with it? I rebuilt the carb in my classic car when it was about 10 years old, but it hasn't been touched either in the last 30 years.

 

[Scott Danforth]

I assume the 4.3 will be better on fuel economy. Is it a significant difference? I plan to use the boat mostly for cruising and water sports.

internal combustion engines used in boats burn 0.4# of fuel per HP per hour. so two motors at exact same hp will burn nearly the exact same amount of fuel (slight variations engine to engine prevent it from being exactly the same).

there is no fuel savings on a 220hp V6 vs a 220hp V8.

you can not argue with BSFC. that is one of those fundamental laws of physics like gravity

if you want fuel economy in a boat, get a boat with oars or sails.

however you can turn the 220hp V8 to a 260+ HP V8. the V6 is maxed out and on the ragged edge of reversion.

 

[mr 88]

however you can turn the 220hp V8 to a 260+ HP V8. the V6 is maxed out and on the ragged edge of reversion.

Scott , do you have link for this upgrade ? I searched in the Mercruiser forum and couldn't find it. Although I do recall seeing that info recently posted there. Thanks !

 

[Bhebert449]

Thanks for all the replies. I am leaning toward the 195 with the 5.0 engine. It is also a 2009
Vs the 205 is a 2007. I like the color and interior on the 195 better.

 

[QBhoy]

Oh man. Some really untrue info being thrown about here. Without doubt a 4.3 mpi in the same model of boat as one with a 5.0 carb...will be better on fuel. Let there be no doubt about it.
Apart from all that. The mpi boat will be more desirable than the old carb 5.0, when time to sell her on. Added to this, the smart craft technology available for the mpi...it’s a no brainer. Especially on a boat like this. Would be an easy choice for me. The 4.3 in any form is just simply a brilliant engine. In mpi form...it simply outshines the 5.0 carb in every area...unless you had the notion to have loud exhausts. Only thing I can think of as a reason for it over the 4.3. Even then....
Also worth noting that this mpi should not be confused with the efi engine, as perhaps indicated in a post above.

 

[mr 88]

Boy it's not the same hull. It does not have the same torque. It is not worth more. It will wear out quicker. The fuel milage difference isn't even worth discussing. Yes after sitting a week or so the MPI will fire up sooner than the carb. After the 5.0 is started one time it will fire up as quickly as the untill it isnt used for a week or so.. Want a bunch of crap , "really untrue info being thrown about here " . To the OP good luck and buy what you think will make you happier.

 

[Bhebert449]

Boy it's not the same hull. It does not have the same torque. It is not worth more. It will wear out quicker. The fuel milage difference isn't even worth discussing. Yes after sitting a week or so the MPI will fire up sooner than the carb. After the 5.0 is started one time it will fire up as quickly as the untill it isnt used for a week or so.. Want a bunch of crap , "really untrue info being thrown about here " . To the OP good luck and buy what you think will make you happier.

so are you saying go for the 2009 with the 5.0?