Briggs & Stratton 5hp - Craigs List AD

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

exhaust back pressure

your dealing with sound waves here that help scavenge the cylinder...

read,
http://www.motorcycle.com/how-to/ho...ambers-work-and-why-you-should-care-3423.html

 

[trendsetter240]

Re: Briggs & Stratton 5hp - Craigs List AD

your dealing with sound waves here that help scavenge the cylinder...

read,
http://www.motorcycle.com/how-to/ho...ambers-work-and-why-you-should-care-3423.html

No you're not, the motor is a 4-stroke.

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

if the noise is too much then clamp a length of emt onto the muffler and route it beneath the waterline.

I was referring to why a exhaust extension run under water would hinder the 4stroke. Or did you miss that part?

 

[OMC-boy5.5]

Re: Briggs & Stratton 5hp - Craigs List AD

I personally would go with an old (50's) OMC 5.5 or 7.5..... Just me though. They are a fair amount of maintenance, but they are REALLY fun motors. They are easy to pick up for $50-75 and then put in about $150 in parts, and you got yourself a practically new motor. Plus, they run really smooth and don't rattle you hand off. I can get my 12' boat on a plane (around 13 mph) with my johnson.

I can see where you're coming from on the backwater swamp impeller problems though.

EDIT: sorry, just figured out he already bought it..... whatever.

 

[trendsetter240]

Re: Briggs & Stratton 5hp - Craigs List AD

I was referring to why a exhaust extension run under water would hinder the 4stroke. Or did you miss that part?

The intake and exaust valves on a 4 stroke are never open at the same time like they are on a 2 stroke. Back pressure on the exaust in a 4 stroke has no effect on fuel/air intake.

Back pressure on the exaust of a 4 stroke will add load to the piston during the exaust stroke. This however is a completely different scenario than the expansion chamber effect described in the link.

cheers

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

Ok you win, now go put a potato in you 4 stroker and give it some back pressure and see how she runs....totally useless conversation here,

 

[trendsetter240]

Re: Briggs & Stratton 5hp - Craigs List AD

totally useless conversation here

Agreed.

 

[RRitt]

Re: Briggs & Stratton 5hp - Craigs List AD

I personally would go with an old (50's) OMC 5.5 or 7.5..... Just me though. They are a fair amount of maintenance, but they are REALLY fun motors. They are easy to pick up for $50-75 and then put in about $150 in parts, and you got yourself a practically new motor. Plus, they run really smooth and don't rattle you hand off. I can get my 12' boat on a plane (around 13 mph) with my johnson.

I can see where you're coming from on the backwater swamp impeller problems though.

EDIT: sorry, just figured out he already bought it..... whatever.

I could not find any air cooled mainstream outboards. I did find some evinrude powerheads in a surplus channel and considered buying a evinrude with a pair of spares. I just don't feel like buying $150 in parts and spending 4 hours fixing the motor 1-2 times every year.

I think maybe a converted garden cart of some type might work. if the wheels are big enough it might roll through floritam grass.

Ok you win, now go put a potato in you 4 stroker and give it some back pressure and see how she runs....totally useless conversation here,

sticking a potatoe in an exhaust pipe is an airtight seal. You are making stuff up without thinking about it.

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

sticking a potatoe in an exhaust pipe is an airtight seal. You are making stuff up without thinking about it.

you spelled potato wrong RRitt, and your absolutely wrong about the air tight seal if you peal the tater, and they will run until you rev it then it will blow the potato out

Put a 4 cycle briggs pipe under water and you will burn the valves or worse....heat RRitt???

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

sticking a potatoe in an exhaust pipe is an airtight seal. You are making stuff up without thinking about it.

I just can't leave this alone, call me a liar and I'm you pet all day.

Restricting a 4 cycle's lawn mower engines exhaust unless designed for it, ie modern 4 cycle outboards, will build up heat and destroy the engine,
Briggs and Stratton had to get past Coast Guard regs to build there 4 stroke and run the exhaust open to the air...has to do with CO output...it has to be that way or as I said it will melt the engine. Oh and don't forget what would happen as the valve's of your replumbed 4 cycle start to burn from the extra back pressure and they start to suck water back up the exhaust...reversion??? RRitt?

My old dad drove his car all day with a spud up his exhaust...rusty Ole piece of junk anyway but it run...just wouldn't pull a hill. once the potato was baked it spit it out...also over heated and warp a valve and blew a head gasket on his 69 rambler rebel. He really had a hard time moving past my little experiment as I recall.

 

[Tom @ Buzzard Bluff]

Re: Briggs & Stratton 5hp - Craigs List AD

<Restricting a 4 cycle's lawn mower engines exhaust unless designed for it, ie modern 4 cycle outboards, will build up heat and destroy the engine,
Briggs and Stratton had to get past Coast Guard regs to build there 4 stroke and run the exhaust open to the air...has to do with CO output...it has to be that way or as I said it will melt the engine.>

DING, DING, DING! We have a winner Ladies and Gentlemen!

<My old dad drove his car all day with a spud up his exhaust...rusty Ole piece of junk anyway but it run...just wouldn't pull a hill. once the potato was baked it spit it out...also over heated and warp a valve and blew a head gasket on his 69 rambler rebel. He really had a hard time moving past my little experiment as I recall.>

Why do I think he wasn't the only one who had a hard time that day?

 

[RRitt]

Re: Briggs & Stratton 5hp - Craigs List AD

you spelled potato wrong RRitt, and your absolutely wrong about the air tight seal if you peal the tater, and they will run until you rev it then it will blow the potato out

Put a 4 cycle briggs pipe under water and you will burn the valves or worse....heat RRitt???

How many hours do you think a small four stroke will go if there is an extra 24" of emt pipe clamped onto the exhaust?

I estimate an impeller based 4stroke engine will suck up muck and need service about once every 2 trips if I drive it like I would drive an electric or air cooled engine. If I am super careful and always turn off the engine before I get to any shallow cuts or mud flats then it might even last a full year. But, then ... why would I even bother having a motor on the canoe? If I'm going to avoid shallow cuts then I should just take the big boat.

Ever since ethanol came out every small engine I have has broken (except the briggs push mower). I'm not going to fix small engines any more. Outboards are no exception. I am not even going to bother checking to see if the plug(s) is fouled. If it does not start or run correctly then I am throwing it in the trash. I can do that with briggs since a whole new engine is only $130. I plan on throwing away about one engine per year. If it was water cooled, then I guess I would be throwing away 2-3 engines a year.

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

How many hours do you think a small four stroke will go if there is an extra 24" of emt pipe clamped onto the exhaust?

the real question is how many hours will a Briggs 4 cycle go with 24" pipe under water holding back the exhaust heating up the valves and cylinder....I would guess about as long as it takes smoke a rack a baby back ribs...say 2.5 hrs or so, if you fish like me you make a 5 minute run here then there and 30 minutes back to dockside...a wild guess 3 weeks of off and on fishing and you can buy that new power head.


PS I have no problem with corn, all it really does is draw water if it sets, I use OMC fuel lines on everything and the corn keeps the engine good and clean,

My 1975 70hp Johnson loves corn, hate's valve tec non ethanol 93 octain marine fuel, I lose 150 rpm there abouts and she carbons up quick.

 

[RRitt]

Re: Briggs & Stratton 5hp - Craigs List AD

the real question is how many hours will a Briggs 4 cycle go with 24" pipe under water holding back the exhaust heating up the valves and cylinder

Why is that a real question? The water isn't even 10" deep and the briggs is built for a 15" transom. Why would anybody stick a pipe 24" underwater?

 

[jaylamb]

Re: Briggs & Stratton 5hp - Craigs List AD

I have a used Johnson 6hp I paid two bills fro running,all I have done is tune it up,I also have a Ted Williams 5hp I got for free,that one the crank was shot I got a NOS powerhead from Certifed parts for under a buck fifty,I have roughly under200 into that one,I had a buddy that had one of those Briggs,it dropped a valve,lucky it was under warranty,the replacement runs ok but I don't like it vibration,limited speed range on the throttle,and its fummy,in the not sweet smelling two cycle way either.If its a motor you'll use once in a while and you could get a little knocked off the price maybe. I use the stabil marine ethonol stuff so far its worked out good so don't let that scare you away from a good used two cycle just make sure you hear it run first.

 

[boobie]

Re: Briggs & Stratton 5hp - Craigs List AD

Remember the old potato trick of being stuck up an exhaust pipe of a vehicle yrs ago. It still takes 4 things to make an engine run.

 

[mrcrabs]

Re: Briggs & Stratton 5hp - Craigs List AD

Why is that a real question? The water isn't even 10" deep and the briggs is built for a 15" transom. Why would anybody stick a pipe 24" underwater?

How many hours do you think a small four stroke will go if there is an extra 24" of emt pipe clamped onto the exhaust?

these are qoute's from you RRitt???...I think I need a beer and you need to lay off...lololo

 

[RRitt]

Re: Briggs & Stratton 5hp - Craigs List AD

these are qoute's from you RRitt???...I think I need a beer and you need to lay off...lololo

Its a boat - not a submarine.
The engine exhaust sits about 6" above a 15" transom with about a couple inches taken up in bends. So the end of a 24" pipe is about 2" under water. Putting the pipe 24" under water would be retarded. It would defeat the whole purpose of wanting an engine that could work in a 4" deep muddy slop.

If the noise is too much then i'll hook up a pipe and see what happens. I can't lose. If it works then I have access to pristine fishing waters that nobody else can reach. If it doesn't work then I just use the bigger boat and pole my way around the edges like everyone else.

 

[RRitt]

Re: Briggs & Stratton 5hp - Craigs List AD

I have a used Johnson 6hp I paid two bills fro running,all I have done is tune it up,I also have a Ted Williams 5hp I got for free,that one the crank was shot I got a NOS powerhead from Certifed parts for under a buck fifty,I have roughly under200 into that one,I had a buddy that had one of those Briggs,it dropped a valve,lucky it was under warranty,the replacement runs ok but I don't like it vibration,limited speed range on the throttle,and its fummy,in the not sweet smelling two cycle way either.If its a motor you'll use once in a while and you could get a little knocked off the price maybe. I use the stabil marine ethonol stuff so far its worked out good so don't let that scare you away from a good used two cycle just make sure you hear it run first.

I could not find a marina type outboard without impeller. water cooled would not survive unless you rigged up a radiator.

 

[OMC-boy5.5]

Re: Briggs & Stratton 5hp - Craigs List AD

I could not find a marina type outboard without impeller. water cooled would not survive unless you rigged up a radiator.

now there's an idea!

And if you're not willing to tinker on anything to do with small engines, then I don't think a small outboard is the thing for you, regardless of being air or water cooled.

And why don't you just get a small inline muffler from something else (along with the stock muffler) and just face it down towards the water. It doesn't need to be in the water, just below the transom to reflect the noise away from the operator

something like this: http://www.mfgsupply.com/m/c/18-8942.html