outboard motor help

[WIP]

so i bought a 5hp Briggs and stratton outboard motor...i have 3 questions for anyone who is pretty knowledgeable about outboards....

1. it is technically a fresh water motor, but i use it in brackish water. so the water splashes up all over the engine (not bad, but enough to notice the salt once it dries) and cover...is there something i can spray on it, like a oil based protectant or something to reduce the chance of corrosion? i already wash it off really good after i finish with it, but i dont want to take any chances as i just bought it 2 days ago brand new.

2. i'm a modifying guy...i like to get the most efficient power out of something by gettting rid of restrictive things on it or adding things to it...so are there any modifications i could do to make it more powerful?

3. it says it is a 4 cycle 5hp engine. from what i understand, a 2-stroke requires a mixture of gas and oil, whereas a 4-stroke has seperate oil and gas chambers....so they never say if it is a 4-stroke or not, just 4-cycle. it does have separate oil chamber and an external fuel tank to run regular gas.... so does this mean it is a 4-stroke? here are the specs:

Engine Style:5 HP 4-cycle, OHV, Air-Cooled
Displacement: 11.5 cubic inches (189cc)
Number of Cylinders: 1
Bore x Stroke: 2.688" x 2.04"
Gear Ratio: 1.57:1
Propeller Diameter - Pitch: 8" - 7.8"
Recommended Transom Height: 15"
Fuel Capacity: 3 Gallon Remote Fuel Tank
Fuel Consumption: 0.5 Gal/Hr @ Full Throttle
Full Throttle: 4000 RPM
Weight: 56 lbs.
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so do i have a 4-stroke?

thanks for any and all replies...reps for most.

[beefstuinit]

wash it with freshwater when your done.

[Haider254]

4 cycle is the same as 4 stroke. Basically a 4 stroke completes the 4 necessary actions of an engine in 4 strokes. there four things being: Intake, Compression, combustion and exhaust. Where as a 2 stroke does the above actions in 2 strokes. The 2 stroke engine is simplified, there are no valves to worry about. the 4 cycle did confuse me a bit but the OVH means Over Head Valves, like I said, 2 strokes don't have valves ;)

Like Beefstuinit says just wash the shizzle with fresh water when you're done ;)

As for squeezing power out of the engine, well most engine manufacturers try to squeeze as much as they can out of their outboards, there are somethings you can probably do just like with a car or a motorbike engine but it will get expensive I would think, loads of custom work... but I was expecting more than 5hp from a 190cc engine :S

EDIT: as for tuning this will probably void your guarentee aswell ;)

[WIP]

thanks for the replies...i was up half the night last night looking up stuff on it. i always wash it off with fresh water before i put it up, but i was just wondering if there was something specifically for protecting against salt. it's a briggs and stratton so it's basically a lawn mower engine with a lower unit and propellor:D...i'm not going to mess with it yet though. i think it is a bit limited in power considering it's size, cause the Mercury 5hp 4-stroke is a 123cc engine, so this one should make a little more power. anyway, thanks for the replies....btw, i'm not worried about the warranty, i know a guy that has a scrap yard for boats, so i could still get 3/4 of my money back at the least if i sold it to him....he pays good if he knows the history of it and since it's me.

[Haider254]

hmm, can you link to the exact unit? how does the throttle system work? I've played around with a briggs and straton before, but that was a lawn mower engine with an automatic throttle. remember though, that thing is air cooled with a case on it(I imagine there's a case on it) so over heating may be the reason behind the low power and high displacement (increase size of the engine to increase surface area to cool down)..