Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

[stracuzza]

ive been debating to go with an older f100 4 stroke or spend alot more money for a 115 4 stroke. I see the f100 is carburated and the 115 is a electronic fuel injected. I own a 17ft henry o center console and im really just gonna be worried about getting better fuel mileage and a more quieter motor. I've been looking around for some pros and cons of these two kinda to do a comparision. Im not sure about the whole carburated vs. E.F.I but if anyone has any input to kinda point me in the right direction that would surely be appreciated. Thanks

 

[robert graham]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

Either would be fine, EFI better fuel mileage, both motors pretty quiet. Personally I prefer carbs, understand better how to maintain them, clean, fresh, stabilized fuel, drain carbs couple of times a year, install fuel/water separator, no problems with carbs. Injectors hate water, can really screw them up. Good Luck!

 

[99yam40]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

EFI is more fuel efficient but more maintenance is required.
But that is what is required to get the fuel efficiency.

 

[stracuzza]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

ok yeah the boat is rated for top hp of 120 but ive been looking and i just came across the f100's and saw that they were a four stroke too. Im just looking for really good gas mileage and wasnt sure if the f100 was a bad choice or not. it came equipped with a 40 gallon gas tank and im gonna be hoping for the best fuel mileage as possible per gallon

 

[JB]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

If you are a DYI you will like servicing the F100 a lot better.

The EFI, however, will be more fuel efficient, more powerful and a LOT more user friendly.

To me, the user friendliness is worth a lot. . .even the PIA servicing.

 

[JRJ]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

I would buy a 115 EFI Suzuki. I put 200 hours on mine and only changed the oils and filters. I wouldn't own a carburated OB again.

 

[rodbolt]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

on this I gotta disagree with JB, and its rare.
the F100 on a good day takes me about 4 hours to remove,clean and reinstall all 4 carbs.
it also takes a 600 dollar 4 channel manometer to reset the throttle plates.
carb kits for the F100 retail for about 107 dollars each carb.
the F115 takes me about 1.5 hours to remove the intake,clean the VST filter and reinstall.
if the injector filters are clogged takes 30 dollars per injector and 20 minutes to R&R them
no way would I own a multiple carb 4 stroke outboard.
othar than the fuel system the rest of the maint is the same.

 

[JB]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

I would take Rodbolt's word for it.

 

[rodbolt]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

best is to find a good working sea trialed engine and simply keep debris and water out of the fuel system and run the thing.
I just finnished a carb job on an F75,4th time this past 9 months, and its a pain.
customer isnt happy and I am aggrevated but its not my fault he has burned less than 6 gallons since last april and every time he gets around to running it the carbs are fouled.

 

[JustJason]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

I couldn't even begin to tell you how many boats with OB's that i've seen from little 9.9's to 250+hp that do not have a fuel/water sep filter installed on the boat.

If your buying a used boat that has a some hours on it that does not have a fuel/water sep filter you can pretty much garuntee it's going to have some fuel system problems sooner or later.
Or if your buying a boat that has a filter.... and the owner says that he doesn't know what it is and it hasn't been changed in 5 years... same things going to happen.

 

[stracuzza]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

well im not a real D.I.Y type person i understand its better to know the motor your dealing with if there is any problems but id rather pay someone that does it for a living and then to take money outta there pockets by doin it myself... dont get me wrong though somethings i can do by myself but i just feel its easier to pay someone esle to do it... ive been comparing these motors on yamahas website by the boat test they do i may lean more towards the 100 than the 115 i really didnt get if there was gonna be a major difference in fuel economy going with the carb or the e.f.i .... would you still have to do a leakdown test on the carb motor as i've read about having one done on the e.f.i motors?? ive only owned 2 stroke motors so im really not fully aware of the four stroke other than what i've read and going out on my friends boats... im really looking for the best bet on the motor for my boat... plus everyone has 4stroke yamahas around my neighborhood and they all love'm im just hoping for the same result

 

[JRJ]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

I used to fish with a guy that had an F100. Sometimes his motor started, and sometimes it didn't. My EFI Suzuki always started, right away, even after sitting for 9 months. It sounds like you are stuck on cards though, so good luck.

 

[stracuzza]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

ive been looking around for a 4 stroke suzuki but not really having any luck... it would be alot better for me to have a suzuki because the neighborhood i live in here in georgia has a huge marina and they actually service suzuki's so that would be a plus to only have to take my boat a block to the marina instead of having to drive all over town to another repair shop... i started out with a 2 stroke suzuki and loved it... maybe ill do some more searching for one

 

[stracuzza]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

ive been looking around for a 4 stroke suzuki but not really having any luck... it would be alot better for me to have a suzuki because the neighborhood i live in here in georgia has a huge marina and they actually service suzuki's so that would be a plus to only have to take my boat a block to the marina instead of having to drive all over town to another repair shop... i started out with a 2 stroke suzuki and loved it... maybe ill do some more searching for one

 

[robert graham]

Re: Carburated F100 4 Stroke Or E.F.I 115 4 Stroke??

Regarding fuel economy, the rule of thumb is that a motor will burn about 10% of it's rated horsepower per hour at full throttle. Of course a fuel injected 4 stroke is going to do some better than a carbed 2 stroke, but that gives you a starting point to figure fuel usage. My 90HP carbed 2 stroke burns just about the same fuel as my brother-in-law's Yamaha 115 4 stroke FI. You can also go to: Yamaha Outboard Performance Bulletins and put in your boat/motor combination for good info regarding GPH, MPH,MPG at all different RPM's. It'll give you your best cruise RPM for best mileage. Bottom line is that all these motors will run great with clean, fresh, stabilized fuel in them AND a good water/fuel separator. Beyond that just basic normal preventive maintenance. Check out the Stabil Marine Fuel Additive at Walmart for $20/gallon. Good Luck!