outboard vs inboard

[gghostrider]

i'm looking to buy a boat and most boats iv'e looked at have outboards which i know a little about but i found a boat i like with a1988 4.3 mercruisor v6 which i know nothing about. Does anybody have any thoughts or opinions on inboards vs outboards or anything specific about this motor thanks

 

[Greg Mrozinski]

Re: outboard vs inboard

Ghost,

Welcome to iBoats! Outboard vs I/O depends on personal preference, type of boat, location intended to be used, trailered or not, etc. So what type of boats do you like? Where do you boat? Trailer boat or not?

The 4.3 V6 has been around for years and parts/replacements are easily available. Pretty much bullet proof if taken care of properly.

 

[gghostrider]

Re: outboard vs inboard

looking for a lund for around great lakes area, mostly going to be trailered. found a 20ft baron just dont know anything about these types of motors plus people are telling me that the lund baron sits pretty high out of the water and kind of hard to fish out of when windy

 

[steelespike]

Re: outboard vs inboard

An outboard is simpler to work on,lighter, factory built for marine application intended to run at the max rated rpm,The 2 stroke outboard has a lot fewer moving parts.
The I/O motor really is at the ragged edge of its design envelope in a boat.
In a car the 4 stroke generally cruises on the highway at about 1800 to 2,000 rpm in a boat
cruise rpm is generally 3200 to 3600. HP is usually rated at about 5,000 5,500 rpm and it runs at the max for a few seconds at a time.In a boat rated rpm is generally around 4,600.Almost 1000 below the normal max rpm.
The 2 stroke could run for hours at its max rpm.
The I/O has many parts specifically designed for the I/O application,universal jounts,gimbal
bearing,upper gears,Torque drive coupler,2 cooling pumps,exhaust manifolds.
The cooling system must be drained for winter storage.Oil changes are a pain.
The cooling system in the outboard drains as the boat is removed from the water as long as the motor is upright.It has fewer less complicated service intervals.

 

[gghostrider]

Re: outboard vs inboard

if i were to look at this motor are there any problem areas to inspect.thanks

 

[Greg Mrozinski]

Re: outboard vs inboard

Ghost,

Steelespike brings up some good points although I think he is being a little biased towards the outboards. The V6 is a marinized automotive engine true, however, the amount of torque it produces is generally more than that of an equal sized OB (except the newer ones). That flat torque curve means that you don't have to run it at full throttle all the time, saving wear and tear and fuel. The outdrive itself does require more maintenance over the life time of the power train itself...but...they are very reliable. So like I said before personal choice really.

Things to look at on the V6 are: general condition of the belts, hoses, wiring, etc.; oil leaks; water leaks; excessive corrosion at the exhaust manifold riser joint. For the outdrive check the overall condition of the drive itself; excessive corrosion of exterior metal parts; anodes present; condition of the bellows and excessive play in the prop shaft.

If you are able to run the motor then check the temperature of the risers when running, use your hand. At idle they should be fairly cool or luke warm at best. When throttled up they should be luke warm or just a tad hotter. Either case you should be able to easily keep your hand comfortably on them. If they are hot to the touch then there is a blockage of the cooling passages.

 

[Silvertip]

Re: outboard vs inboard

If you intend to boat the Great Lakes or larger bodies of water, you will appreciate the fact that most Lund boats, have rather high sides and as a result can handle very rough water. Fishing from them is simply not an issue unless you routinely fish for a specific species that requires a low freeboard and off hand, I can't think of any that would require that. The 4.3 V6 engine has been around in varies versions for decades and appeared in GM vehicles in the mid 1980's. Engine parts are readily available from various sources including Chevrolet/GMC dealers. Some parts like core plugs and gaskets are marine specific but generally any auto store can get you the basics. Ignition and starter components are marine specific due to the ignition protection requirements. I've owned both I/Os and outboards and also tend to favor the outboard. For the same size boat, an outboard takes up much less interior space and servicing the engine is definitely a pain in the backside on I/Os. With an outboard, if you love the boat but hate the engine you can sell the engine and replace it with any manufacturer. If you love the engine but hate the boat, remove the engine, sell the boat and buy what you want. With an I/O you are stuck with what you have and the only option is to trade boats although some engine swapping is possible (such as a 5.0 V8 to a 5.7 V8) but those choices are rather limited from an economic standpoint.

 

[Greg Mrozinski]

Re: outboard vs inboard

^^^^good points. Personally I would go for an outboard also but was trying to answer the question asked.

 

[QC]

Re: outboard vs inboard

The V6 is a marinized automotive engine true, however, the amount of torque it produces is generally more than that of an equal sized OB (except the newer ones). That flat torque curve means that you don't have to run it at full throttle all the time, saving wear and tear and fuel.

Two Cycles typically produce higher peak torque as they fire twice as often. In either case a flat torque curve results in better hole shot, but has almost nothing to do with cruise. Propeller load "curves" are linear. Straight diagonal line going up with RPM. Unless the throttle is "mashed" or at WOT, you are NEVER utilizing peak torque at any RPM . . . Sorry to be emphatic, pet peave

 

[Greg Mrozinski]

Re: outboard vs inboard

Two Cycles typically produce higher peak torque as they fire twice as often. In either case a flat torque curve results in better hole shot, but has almost nothing to do with cruise. Propeller load "curves" are linear. Straight diagonal line going up with RPM. Unless the throttle is "mashed" or at WOT, you are NEVER utilizing peak torque at any RPM . . . Sorry to be emphatic, pet peave

Ok. Agreed. That's why we have two cycle engines right...instant power. I should have been more clear I guess. Anywho, bottomline is the V6 will develop good torque and move that boat just fine and use less gas than a two stroker suitable for the same boat. I am referring to the older OBs not the newer E-tecs per say. Again...personal choice.

 

[QC]

Re: outboard vs inboard

All good, like I said pet peeve I am on a one man (trust me, very alone here) crusade to correct the confusion over the value of peak torque to wheeled vehicles vs. propeller driven ones. Very different applications of torque and ultimately horsepower . . .

 

[SparkieBoat]

Re: outboard vs inboard

I can find I/O boats for sale cheap around here cause most people do not like them..especially if they are over 10 years old..you run into many issues. I would not even consider an I/O for a boat under 30'. many people have even purchased the 24" jack plates so they could put outboards on a I/O boat, I have an old 18' aluminum one That I am waiting on a deal on a jack plate so I can put a outboard on it, it is a really cool old boat but I aint messing with an I/O..so I am not biased or nothing .I just hate I/O motors...LOL

 

[gghostrider]

Re: outboard vs inboard

would you guys say that most boats (lunds imparticular) that have i/o could adapt to an outboard

 

[PopsRacer]

Re: outboard vs inboard

Outboards can be used in the winter time whereas a I/O has to be winterized... My little brother pokes fun at me because he's been going out fishing while I need to wait until spring. - lol