New J Engine?

[14-H]

In the never ending quest to bring new equipment to our sport, the APBA ranks combined effort with the AOF ranks at the Ocoee SE Divisionals to unleash a potential new submission for the Junior Category. Carl Staron brought his mini-most outfit with the 5 hp Briggs & Stratton Four Cycle outboard for a little test run on a hydro. The Briggs 5hp has a bigger displacement than any other 5hp engine and a rev limiter. The Briggs is 12 cu.in. while others like the Merc are around 8. Carl hooked up a throttle linkage, steering bar, gas tank and disconnected the rev limiter for a test run on one of the Mackrell's B&H hydros.

Attached are some of the photos of the run. We hit the water with success getting the boat on plane with the first run. After jacking it up too much, we couldn't plane it off any more.

Next step in the project will be to make a racing propellor for the unit to see if we can get the RPMs and speed up. We ran this as a totally stock set up with the exception of the rev limter being disconnected. The stock prop looks like one off of a trolling motor. With a little more pitch and blade area, we ought to get some decent speeds. Look for an update by Memorial Day and then we'll think about approaching the J Committee.

Oh yeah: total cost for the engine: $650 and you can buy it at any Bass Pro Shop or on line. Eddie.

[Andrew 4CE]

just out of curiosity... how fast did it go totally stock? It would be cool to see a true "stock" class, prop and all.

Was it faster on the hydro or mini-most? How big was the hydro? Standard J size?

[14-H]

Andrew: It ran about 25 mph on a current model J/A boat. The prop is dinky and has no blade area or pitch. We're working on a prop that'll give 'er some speed. We could do the same thing we do currently with the J's and have universal racing props to put on this engine. The cost'd still be less than a current J/A gearbox for this whole unit. Ed.

[ricochet112]

Andrew: It ran about 25 mph on a current model J/A boat. The prop is dinky and has no blade area or pitch. We're working on a prop that'll give 'er some speed. We could do the same thing we do currently with the J's and have universal racing props to put on this engine. The cost'd still be less than a current J/A gearbox for this whole unit. Ed.

Except the gearbox won't take much more revs than in stock form with rev limiter removed. Rev limiter set at 4K.

2 reasons this engine sucks, it's air cooled only, and it's a 4 stroke.

This motor has been a pain for all B&S dealers because dealer cost is $680.51 plus factory (and local) freight charges. The internet discounters have ruined this for Briggs & Stratton selling them below dealer cost.

I just called my distributer, to find out the model number so I could check some prices. He was very leary about this motor used for racing, and so am I.

If it is raced, I will buy all the gearcase tools and stock gearcase parts because, THE GEARCASE WILL BE DESTROYED!!!!!!!!!!!!!!!!!

There are no bearings in the drive shaft, bushings only.

Drive shaft carrier input (drive shaft bearings) assy. $81.90
Gearcase housing empty, no complete assy available $195.80
Forward gear $70.35
Pinion gear $19.50
Reverse gear $47.50
Prop shaft $118.80
Total $533.85

Gearcase parts= 78% of the dealer price of the motor for the major parts that WILL fail if the motor is ran over 4k RPM's for any lenght of time. IF the gearcase holds up and the engine is run close to 6K RPM's it may last 1-2 hours of run time in STOCK form.Now we'll have to deal with MAJOR refinements to keep the rod on the crank and the push rods straight!!!!!!!!!!!!!!!!


For a comparison, THINK ESKA!!!!!!!

PS, the camshaft is composite, think plastic gear
PSS, how many rev's will a cast iron flywheel take?

[14-H]

Except the gearbox won't take much more revs than in stock form with rev limiter removed. ***take?

Mike: I intend to tear one up! At that price, one per year should do it. Ed.

[aojesus]

good deal

This motor has been a pain for all B&S dealers because dealer cost is $680.51 plus factory (and local) freight charges. The internet discounters have ruined this for Briggs & Stratton selling them below dealer cost.

Drive shaft carrier input (drive shaft bearings) assy. $81.90
Gearcase housing empty, no complete assy available $195.80
Forward gear $70.35
Pinion gear $19.50
Reverse gear $47.50
Prop shaft $118.80
Total $533.85

Gearcase parts= 78% of the dealer price of the motor for the major parts that WILL fail if the motor is ran over 4k RPM's for any lenght of time. IF the gearcase holds up and the engine is run close to 6K RPM's it may last 1-2 hours of run time in STOCK form.Now we'll have to deal with MAJOR refinements to keep the rod on the crank and the push rods straight!!!!!!!!!!!!!!!!


For a comparison, THINK ESKA!!!!!!!

PS, the camshaft is composite, think plastic gear
PSS, how many rev's will a cast iron flywheel take?

So $533.85 plus another, let's say, $150 and you have a complete motor. Take it all apart and put the pieces on a shelf for spares. Crank case, fly wheel, piston, rod, carburetor, gear case, you will have all the replacement parts on your shelf for a total rebuild for under $700. Can't do that with a Mercury or any other brand.

Or, you could take the blown up motor and use it for parts. Very economical motor.

[14-H]

Parts

Leave the reverse gear out and save 50 bucks. Probably don't need that unless you anticipate a crash in the first turn.

[14-H]

Cost

Hey Mike, knock off $200 bucks 'cause you probably won't need a new housing and that's $335.00. That's less than I paid for the rebuild on my last Hot Rod lower unit. Later, Ed.

[aojesus]

Oh no

For a comparison, THINK ESKA!!!!!!!

We would then need to think about a parity committee

[ricochet112]

Leave the reverse gear out and save 50 bucks. Probably don't need that unless you anticipate a crash in the first turn.

The reverse gear holds the pinion in, can't take it out.

The motor will NOT withstand any type of racing at all. Unless you want to rebuild it it every 4-6 heat, 8 if you're lucky!?!?

The engine was designed for a lawn mower, 6 HP Intek design. The outboards have not sold well because they are marginal to begin with for fishing and trolling ,when they first came out they had serious overheating problems at idle.

THIS WOULD BE A VERY BAD MISTAKE TO PURSUE THIS B & S MOTOR !

It would make much more sense to use the Merc 15 and keep the fishing gearcase on it, the whole package is proven. B&S is very new in the marine market, and it hasn't been a stellar introduction.

I don't want to be anywhere near this engines cast iron flywheel when it's spinning over 5K! No one wants to endanger kids!

[ricochet112]

We would then need to think about a parity committee

NO NO NO NO, please NO parity committee.

IF you could FIND the last 3 running Eskas

Eskas were air cooled disposable outboards with similar gearcase designs.

[Bill Huson]

Or how about . . .

British Seagull outboard! Fav mill for ragboaters on their dinks.

[STEVE FRENCH]

The reverse gear holds the pinion in, can't take it out.

The motor will NOT withstand any type of racing at all. Unless you want to rebuild it it every 4-6 heat, 8 if you're lucky!?!?

The engine was designed for a lawn mower, 6 HP Intek design. The outboards have not sold well because they are marginal to begin with for fishing and trolling ,when they first came out they had serious overheating problems at idle.

THIS WOULD BE A VERY BAD MISTAKE TO PURSUE THIS B & S MOTOR !

It would make much more sense to use the Merc 15 and keep the fishing gearcase on it, the whole package is proven. B&S is very new in the marine market, and it hasn't been a stellar introduction.

I don't want to be anywhere near this engines cast iron flywheel when it's spinning over 5K! No one wants to endanger kids!

Is this this the same powerhead that the Go-Kart folks have been run'n over 8-10K rpms for years with governors removed, on al-co-hal ?...(SPELL CHECK! )

19P ..."All we're ask'n .......is....give----- LUV------....a CHANCE.............BEATLES"

[ricochet112]

Is this this the same powerhead that the Go-Kart folks have been run'n over 8-10K rpms for years with governors removed, on al-co-hal ?...(SPELL CHECK! )

19P ..."All we're ask'n .......is....give----- LUV------....a CHANCE.............BEATLES"

No thats a flat head, side valve engine, horizontal crank.

The guys that are spinning that fast have very few original B&S parts left in their engine. Dry sumps, special blocks, cyl heads, valve trains, forged cranks, billet rods...almost completely aftermarket from the ground up!
I though JR dragster (and go karts) looked fun until I found out that most guys have about 1-2K (and up!) into their 5hp B&S!!!!!!!!!!!!!!!!!!!!

In stock form a standard 5hp horizontals' con rod will "exit the building" about 6K.

The 6hp vertical crank over head valve "rotary lawn mower" engine that Briggs has adapted to the outboard wasn't designed for marine use, or anything other than cutting grass. RPM's are set for max life span and max torque at 3,100-3,300. Overall max RPM is 3'600-3'750. They will grenade at close to 6K, and shake themselves apart at 4k-5k.

It's also been used on pressure washers and generators, price point models only (think CHEAP P.O.S.), and they will work a couple of years for most consumers who only use them 4-5 times (2-3 hours) a year. Whereas a lawn mower will last about 7-8 years, at an idustry average of 20 hours a year.

This outboard will need major improvements/modifications to be a viable race motor. Then it will not be close to STOCK.

Pick any outboard and use the stock fishing gearcase for a cheap J motor, not a disposable air-cooled non-proven one!

It has nothing to do with luv, it's about making intelligent decisions.

ADD: IF the rev limiter is left on it MAY last a little while, if you want a 20-23 mph J class.

The connecting rods in ALL air-cooled engines don't have a bearing, the machined aluminum rod IS the bearing. ALL REAL outboards use needle bearings on both ends of the rod. That's where the higher RPM's and engine life come from!!!
Also REAL outboards have needles or ball bearings on the crankshaft mains, the B&S Intek uses bushings only!!!!

[17W]

Plain & Simple!

It's JUNK!