Briggs n Stratton Outboard

[sal3030]

Hello,
I obtained and rebuilt the lower from a 1956 Johnson AD-10M 7.5HP. I successfully coupled it with a Briggs N Stratton "L Head" 6hp from a power washer. It is essentially the same engine except for the OHV head used on their Outboard. My question... Does anyone have a "real" one that they could take detailed pictures of the complete throttle linkage system? I have one in place but would like to improve it. I am using the same twist mechanism from the Johnson. Thanx

 

[mrcrabs]

Re: Briggs n Stratton Outboard

No BS expert but look into your jetting, in dealing with mini bikes I learned that engines that were used to be run at say 3400- 4200 rpm max under a load could be rejetted to give some kick when you firewall it by rejetting them

 

[fucawi]

Re: Briggs n Stratton Outboard

yes have an original and the manual ..you will not re construct the linkage .not the same ..electronic rpm limiter not flap..forget the origial carb .fit a mini bike carb and raised fuel tank ..original has a fuel pump

 

[sal3030]

Re: Briggs n Stratton Outboard

I converted it to a mikuni feul pump already taking the pulse from the oil fill tube. Works great. If I change the carb it may start problems. Ie: mating it to the block, governor arm etc. I don't want to drive it over 3600 rpm and kill it. I just wanted to see how they connected up the throttle linkage.

 

[mrcrabs]

Re: Briggs n Stratton Outboard

here is a youtube of a home made briggs conversion...he's using a bowden cable for a throttle, which seems to be the most feasible method I have seen
http://www.youtube.com/watch?v=vN5NwGYeg_8&NR=1


I see your from New Fairfield, CT. I have a buddy that lives there, non other than Mr. Ed Stoller and a great contibuter to the Eska outboard group and our cause....I guess I should say the savior of the friends of the Solid State Ignition's of "The Dependable Eska"....he tells me he's eating lobster today at a big church cook out, are you going to?

 

[steelespike]

Re: Briggs n Stratton Outboard

Can't help on the linkage.
I can see that this is kind of a fun project but the gear ratio is set up for a motor that
is designed to run at 4500 you'll be about 1000 rpm short.Your probably be running at 4 or 5 hp speed using fuel at a 6 hp rate,with lots of noise,vibration and heat.
Years ago I did rig up a 3 1/2 hp briggs horizontal shaft as a straight inboard with
a water cooled exhaust.A fun project but never did work very well.

 

[sal3030]

Re: Briggs n Stratton Outboard

No lobster for me. Does he have power? They didn't for a week.
Mine works great. Just short throttle twist. May be I could change the carb? Mine doesn't run hot not anymore noisy than a briggs normally is. I used Love Joy axle couplers to limit vibration axle and radial play. I may be shifting at a higher rate than the leg was designed for but the dog still looks good.

 

[mrcrabs]

Re: Briggs n Stratton Outboard

He had been out of town for a tractor show when it hit, he said no power or cable until about 2:30 Thursday, yard scattered with limbs and leaves.

Is your briggs working off of a govener style throttle or direct connection?
Thats the thing I don't like about the briggs conversions is there carb and timing sytem....the Tecumseh 2 strokes are real power houses in a very little package with a real timing & fuel linked & sync thottle system.

I bought a 7/16 drive shaft splined 5/8 Eska direct coupler a few months ago from fleabay for just a few bucks just incase I ever got the itch to do a conversion of some sort....

 

[sal3030]

Re: Briggs n Stratton Outboard

I tried the direct linkage and the engine is too eratic. I went back to the governor. I don't thinks they can be really run (at least mine) without the governor. Little movement of the butterfly made it act wildly. I wonder if a mikuni carb would be better. I also can't get it to idle lower than 1500 too

 

[mrcrabs]

Re: Briggs n Stratton Outboard

I tried the direct linkage and the engine is too eratic

timing advance is either electronic or non existent, my money is on a fixed timing setup on the BS...when you control both timing and fuel delievery things become less eratic

 

[fucawi]

Re: Briggs n Stratton Outboard

Now listen up an learn.....the original 5 HP b &s has a direct linkage to the trottle ...no little plastic bits and springs a big arm and a wire to the throttle ....No flaps just an electronic rev limiter that cuts the igniton at 4000 rpm ( this is why they are sold because out of water they seem to be missing ..on the water fine 3600 rpm loaded by the prop)

The timing is fixed no contacts a magneto with built in electronics.....thats why it wont idle lower than about 1300 ...its not a car you will not get 750 whatever you do ...flywheel mass etc to consider... It fires like a 2 stroke every tdc. if you fit a pit bike carb you will have easy cable to control throttle and an idle screw along with a 5 positon needle to adjust the mixture .
The gear ratio is 1 : 1.5 rather than the 2 ish on most outboards the prop is 8 x 8

 

[sal3030]

Re: Briggs n Stratton Outboard

"Listen and learn" I know all that. I can't get it to idle lower with the governor in place. It fires twice in the four cycles wasting a spark because it has no timing advance other than the magneto. Again, I know this, I don't want it to be a car. I just asked if I could learn more about how they linked it up. Mine works as is. I know little about single lunger engines or outboards. I would be interested in more on changing the carb.

 

[sal3030]

Re: Briggs n Stratton Outboard

I know nothing about pit bike carbs. If the C-C on the mounting face is 1 7/8" wouldsomething like this style work? Where is the throttle linkage? What is that on top with the black tube?
http://www.partsforscooters.com/114-6-4-stroke-19mm-carb?sc=2&category=13

 

[mrcrabs]

Re: Briggs n Stratton Outboard

the black tube is your bowden cable, the throttle cable, here is another pit bike carb
http://www.motopartsmax.com/index.php/main_page/product_info/products_id/514/tID/2/cPath/13/eID/26

 

[sal3030]

Re: Briggs n Stratton Outboard

Thanks. I never heard the term Bowden. I researched and learned that. Funny, I ordered the one you showed me before I read your post. I just don't know how to hook up the double feed lines.

 

[sal3030]

Re: Briggs n Stratton Outboard

Mrcrags,
What is the down facing tube with the mitre cut on the end? Also what is the other brass fitting facing up for? The long black tube going to the bowl is the main fuel line I assume?

 

[mrcrabs]

Re: Briggs n Stratton Outboard

the tube facing up I would guess to be the main fuel line....the others I have no clue except the taper cut tube is probably for when you get the dirty side facing up , things have changed so much in the last 20yrs and other than a Lifan 97cc G100 honda knock off I'm just a simple Johnnyrude, Tecumseh loop charged shadetree mechanic, and I have a fair amount of experience with E30 & E39 Bimmers top to bottom....

 

[sal3030]

Re: Briggs n Stratton Outboard

Thanks,
My father is a mechanic, but he is 75 and says the same thing about things changing. I don't think this thing is going to come with instructions. If nobody here can tell me what the nomenclature is I will have to take it to a minibike place and ask. I may get somew laughs out of them.

 

[fucawi]

Re: Briggs n Stratton Outboard

There is only one pipe neccessary the fuel inlet the other is just an overflow from the float chamber to vent fuel in a very rough ride....Your bad idle is nothing to do with the governer vane etc its just timing is about 20 deg BTDC which means it wont run below about 1300 rpm ...you need near tdc for that ... The throttle on the real thing is cable running direct to the throttle flap...no springs flaps ect...this is what you will get with the pit bike carb

my version of a briggs outboard
a b and S with a water exhaust
pit bike carb on a British seagull ...

 

[sal3030]

Re: Briggs n Stratton Outboard

I didn't know they were that far advanced. Any closer to TDC and they would lose power stroke. Thanks for the pics. Is the main fuel coming into the bottom of the bowl? In your pic I can see the upward facing fitting with a clear tube (not clamped) what is that connected to? Thanks