Carburetor Swapping: BOLT ON MORE POWER!

[@austinmcgrath6434]

hey fearless, i am actually in the process on building a lifted mower. i have used many of your ideas and tips including this one. thanks man. mower has a lot more power now

[@victoryfirst2878]

Could you please tell me the largest flat head motor Briggs made ??? How many years did they make the motor ???? Thanks and nice video fella too.

[@3DMachines]

Walbro are much better Carbs.

[@Fearlessfront]

yea, a way simpler design

[@paulc8581]

3DMachines do you know that a lady stole one of your shots u recorded. The one where u run the john Deere into the garage door .

[@huntercorle317]

3DMachines just think 2 years ago your KZbin was way smaller and now look at you

[@paulc8581]

That's what I was thinking. Hey he still has those earmuffs. Lol

[@gergemall]

FearlessFront (Todd Christopher) simple is good !!

[@GoodGamerDude]

Haha did this yesterday to a buddy's mini bike. I screwed up the old carb for the little 3.5hp Tecumseh. So we tore his old 5hp Techumseh push mower apart and put the carb on the bike it is wicked fast now.

[@EnginesandElbowGrease]

I'm glad the carburetor that I sold you worked the best! hahaha

[@Fearlessfront]

Yeah, It rips now!

[@EnginesandElbowGrease]

So cool!

[@PIGGY603]

LaPavoniMac

[@markwood5477]

What if u drill holes in the flywheel to remove some flywheel weight

[@garyalensr]

I have that same exact tractor that is behind when your talking about pulley swap that's friend has given me. CAN YOU PLEASE TELL ME WHAT YEAR AND KIND IT IS??? I WAS TOLD MINE IS A 90s Murray.. please help me out. IT WOULD BE AN AWESOME BIRTHDAY PRESENT AS TODAY IS MY B-DAY 7/4/2021

[@deathmight7063]

hey fearless love your vids. im looking for a carb like this for mine do you know the specs of this carb. So i can try to find one for mine.

[@itsjustcam247]

Hi, I was wondering if it would be possible to somehow attach a motorcycle turbo or electric supercharger to a mower. Would need quite a bit of fabrication but if Roadkill can work a diesel turbo on the Rotsun then why not. The mower I have is a Westwood T1600 with the same (or similar) as the Mud King's flat twin. Just thought it might add a few horsepower on the larger engines.

[@Franker420]

I've got basically same set up.I blew my 17.5 Intek and all I could come up with for a motor was a 12hp Briggs with no carb or starter so I switched out the carb,starter and flywheel and bada bing been romping it like that for a few hard months now and no signs of any problems yet

[@nicholassmerk]

Did you port the intake manifold and intake port? Did you smooth over the screws inside the carb? Did you tune the mail jet? Tuning the main jet may help with the low RPM. Do those carbs have any kind of intermediate circuit? I know on cars, you can cut the idle passages shallower or deeper to help off-idle, along with the power valve (in a Holley).

[@Fearlessfront]

yea, it was ported about 8 years ago. I did a full rebuild back in the day. new internals, porting, milling the head a lil bit. Nothing too crazy tho

[@rednecklife-uu3je]

Nicholas Smerk The Main jet is a High end power jet, a Pilot jet is your Low end power jet.

[@nicholassmerk]

No shit sherlock

[@rednecklife-uu3je]

Nicholas Smerk You said Main for low rpm you DUMB FUCK...

[@nicholassmerk]

redneck4life887 your right, the main jet won't do much till you transition.

[@468delray]

wondering if there is someway you could richen the low circuit more so it's more responses. have you look into that?

[@8jimi8]

Your videos rock and are very helpful im just getting started on a mower someone gave to my dad it has a 17hp brigs on it my dad has a pull behind tiller so im going to make it a pozzi so it has good traction any advice on how to make it pull harder at a low speed. like pully mod?

[@zachsgarage4714]

I can see what you mean about the Nikki carburetor, it has a lot of spitting and sputtering in the mid range rpm's, the Walbro carburetor takes care of all of that on mine, it runs clean, and nice now, and I have better take off. I did modify my Nikki carburetor, but the Walbro carburetor runs whole lot better.

[@MrTheHillfolk]

Cool to see you getting into tuning a little. It's fun to learn about tradeoffs and it's a miracle when it does everything ya need. It's kind of like the time I used a set of gs 750 carbs on my kawi kz650 "dirtbike". Wack the throttle at anything under 4k and it bogged out, but roll it on slow, or wait till about 6k to hit it , and it would sail past redline about 1500rpms over before it fell off. Yea, big carbs hurt velocity at low Rpms, fuel doesn't atomize nicely, ya get bogs and stumbles. But let it get up on the pipe and it sings!!! Not a big deal, just rev it higher and pop that clutch!! It's too bad these carbs don't really have any adjustments to them, and it's actually surprising that they work as good as they usually do. I suppose if ya wanted to get crazy you could do some research on changing the intake runner length and that will also move the power to where you would want it, and in conjunction with a exhaust of a certain length it'll work good from mid to top. These engines are so small it's probably not worth it to tune em for torque. Tune em for revs. A little off topic sir, but has anyone ever tried adjusting timing? Maybe slot the coil holes to move it back and forth , or make some kind of adjustable base for a coil. I'd take a guess, and say these engines could use more advance,but I'm sure the racers know some secrets.

[@Fearlessfront]

Yeah, people do adjust timing. we would usually use custom cut flywheel keys with an offset. I would want a billet rod and stiffer valve springs if I was gonna do that though. This motor has definitely been modded. like 8 years ago I totally re-built it. Thats why it's the way it is.... NUTS!

[@moparman9564]

i just recently got a murray yard king with an 18 hp twin motor on it and it has an opposed carburetor thats complete junk. can i put a different type of carburetor on it or does it have to be an opposed carb? im new to riding mowers

[@jacobmiller3940]

Hey I have a 17hp motor do you know any bigger carb I could fit on mine? I wanna find a 18 twin and let the 17 on it take. Year rebuild the 18 have it bore and put a bigger pully on the front, could you help? Just for the 17 till I get a 18

[@inhumandday]

hey fearless do you think I could register my mud mower for the atv trails. and if so what would I need

[@thekingsilverado9004]

I'm asking everyone on this thread to give me a hand with an idea I have. I bought an older 1985 John Deere 170 riding mower in nice shape although it has a very expensive Mikuni carb and it's bad. I don't see the thrift in buying a $300 carb for the tractor when I only paid 50 bucks for the damn thing. I have an old Walboro style carb off a Kolher engine I fixed. I figured on ordering a that carb new and putting it on the tractor because seems fine and the linkage seems like it will fit right together.... The only thing is the tractor has a mechanical fuel pump the Kolher engine just had the gravity feed. Is it possible to make this work without having a catastrophe on my hands? Will that Walboro design handle the pressure of the mechanical pump and the work on the Kawasaki engine in the Deere? As stated it seems like it will bolt right on no problemo.

[@MOSTAFIZURRAHMAN-ht2qz]

after so many years it's still helpful I guess. I am planning on installing a bigger carburetor on my motorcycle. Hope it will work ok !!

[@pl747]

A little off subject but I was wondering what camera, make and model, you use making your videos? They come out great.

[@tombradley5106]

hey fearless im kinda new with this youtube thing so bear with me but I have a 14 an a half opposed twin on my mower running a 5 to a 4 pulley ratio and when I drop the clutch in 4th or 5th gesr it bogs down rlly low or dies so if I took a carb off of a bigger motor it would get more air and not bog?

[@vincentip83]

Hi so I swapped a 16.5 ohv carb one the same 12.5 flathead and I can't get it to tune right any ideas? Do I need to reject I cleaned the carb good

[@aserta]

Lucky that there was something to get it stuck in. Out of curiosity, had they not used the same flange would you of had fabricated one??

[@Fearlessfront]

they are the same flange, just use your original intake manifold.

[@DATSUN72067]

Can I use a 14 horsepower carburetor on my 12 horsepower Briggs Or can I use vitro horsepower carburetor and drill the jet out a little bit

[@prancstaman]

Good choice. You don't need that low end power to much anyway, just get in to the habbit of down shifting sooner to keep rpm's up.

[@jimcatx3090]

Make a dual carb set up with long runners and port the hell out of it and port the exhaust

[@sarahkalvelage7377]

couldnt of you just swapped jets? although i understand the bigger bore but i wonder if just a jet swap would have the same effect?

[@redlinemotorsportts]

Noobs be like: Gunna try a 850cfm now lol

[@zragevii4705]

Now I have to hook several inline just to run an 850cfm......😂

[@michaelbenoit248]

What you could do is get some long sections of all thread rod & bolt on like 2-3 carburetors, & get way more power! Lol 😂.

[@cotton123ful]

Thanks man that is some usefull info,i'm working with a nikki carb now on 17 hp craftsman,all the jet's were missing,so I ordered a new carb,maybe I should of got a walbro instead,oh well.

[@SpaceboyA55]

Why is the carb. for a 17 HP engine smaller than the one on my 3 HP moped?

[@zacharymoen1171]

Tyler Kobs probably because it's a moped and meant for cruising not working

[@obfuscated3090]

Smaller venturi for higher velocity at lower engine RPM.

[@overbuiltautomotive1299]

try this one linkage [flapper is reverse of stock carb ] but works well large bore fully adjustable idle and MAIN jet ! and cheap. i bought 3. works well on the 17hp briggs with no governor i imagine one could make it work with governor by making a direction change linkage deal on pivot but any how .great video. but i also use various bike or atv carbs but long runner intake is key to low end power .and larger jets drilled out most of the time

[@MrMiles40]

i have governor issues (16 ohv kohler with walbro carb) it runs fine at low throttle but when I move throttle to normal run range (about half way) the rpms go crazy high. I tried adjusting the governor linkage at bottom of motor, the air fuel adjustment as well as the throttle set screw: a few people said this was more of a carb issue rather than governor. Your thoughts.

[@Fearlessfront]

sounds like the main jet might be partially blocked with crud. try cleaning it out

[@joshge6325]

your gonna need stiffer springs and new halves roller rockers and a transbrake

[@Shaggydogify]

i need to do a carb upgrade really bad but i have an older flathead. what are my options?

[@br1zzl395]

where is a good place to get a used carb I got a cramps man lt 1000 with the 18 hp briggs intek engine and I paid like 30 bucks for the entire tractor it didn't come with a carb and I cant see spending a 100 plus bucks for a brand new one any help would be wicked awesome love the vids by the way

[@NoPaintGarage]

+b1zzl3 If you have a local junk yard or bone yard go there. we have an awesome one where i live tons of car parts and if you look carefully you can find lawn mower stuff too

[@VGstoof]

Do a top speed test on that Murray before the snow flies!

[@rev9fan1]

I actually ported and polished the intake manifold on my brothers riding mower and it made a noticeable difference when he climbed a steep hill, I think at first he needed 2nd gear to get up, then he was able to get up in third after I did the mod. With this carb you may want to try to port and polish the intake manifold, free horse power!!

[@Fearlessfront]

that was done long ago!

[@rev9fan1]

Makes a big difference doesn't it?

[@codyviens4521]

I have question what kind of motor should i put on my murry. i just blew the motor me and my friend beat the crap out of it and she finely blew out in my swamp it has 15.5hp with a swapped pully in the back for tork and it could use a new steering set up and rear end. and i also run 2 kc head lights on it. i use it for every thing

[@Fearlessfront]

I love me a briggs single cylinder! try to get an I/C model. They have a cast iron sleeve.

[@EoC_ReaL-SpYDeR]

hey todd. im working on a 21hp vtwin ohv briggs in a murray select. bout to do the pulley swap. but got any advice on which carburetor i should use with that big motor

[@allenmckinney9533]

mike spyder i got a 2 barrel chevy carb you can try.

[@mudrut4x49]

hey fearless do you have another one of those 17hp carbs? i need a new one for my mud mower pls respond soon

[@bamataz13]

Fearless I really have a couple if questions,I'm into this stuff and I've seen slot of vids but why do you shift? You don't really need a clutch for a lawn mower and why'd you out the brake where the shifter is,I like the setup but I was just wondering,braise I remember the Murray before you did all that I subscribed back when you put the flares on the Murray actually before that,and it didn't seem like the brake"clutch" was giving you a problem,so if you could please make a vid explaining why you decided to put the brake on the shifter,and why the it's not where the"clutch" is anymore and just explain a lil bit about the ole girl and also please make some more side x side vids

[@Fearlessfront]

the brake was removed completely in the beginning. It wasn't until I installed the new transaxle that I decided to rig up brakes. So the clutch was never attach to the brake to begin with. You don't want it on the clutch because you wouldn't want to stop for a 4th-5th gear shift. That would be dangerous.

[@bamataz13]

Oh okay,thanks man it's just every mower I've seen the clutch was basically the brake but thanks man,YOU ARE AWESOME!!!!(:

[@Fearlessfront]

bamataz13 yeah, it works ok for low speeds. Thanks!

[@eastamericantrains589]

I’m surprised you were able to swap carbs and get a better result. I swapped carbs off of an 11hp flathead to my 8hp flathead and the 8hp would not idle at all when my throttle was at idle the engine took off and ran way past the governed speed even if I held the carb at idle with my hand.

[@siraugustwinter]

Ever come by a part number for that carb you put on there?

[@WeldstarCreations]

I prefer a Walbro over a Nikki. Nikki carbs are made in Japan and their rebuild kits are crazy expensive while the Walbro rebuild kits are cheap. The Walbro is every bit as good a carb as a Nikki. Great video.

[@Fearlessfront]

I agree, Thanks!

[@restore56]

yes my Murray has an opposed twin and I never have bogging problems I noticed watching you drive before how bogged down the engine seems compared to mine of course it's a whole cylinder difference.

[@nicholassmerk]

I have a 18hp that I'd really like to set up dual carbs on.

[@Keiser1]

how much u want for the twin

[@nicholassmerk]

I think I'm going to keep it for my kids to mess around with it. It wouldn't be cost effective to ship it, you can get complete mowers for $100 on craigslist. I gave up on the mower and got a much nicer one for $100.

[@Keiser1]

oh well im looking for a twin thats the thing and only have like $65

[@nicholassmerk]

Where abouts? I see them (opposed twin L-heads) around Pittsburgh from time-to-time for fairly cheep.

[@PaulsPlace]

Dude i got first dibs when you sell that mower...LOL

[@swompbuster6572]

when will you start the golf cart bilud

[@enniofolini8755]

hey fearless, i mounted a mikuni on mine from a robin (about 15hp) and works absolutely brilliantly

[@Fearlessfront]

Good deal! Just keep an eye on your spark plug... Take it out and read it after the first few hours to make sure it's not too lean, or rich. Mine runs a little on the rich side, which is better than being too lean.

[@enniofolini8755]

sounds good! thanks!

[@9102jack]

Fearlessfront Lean means you burn up top end parts. Too rich means your EGTs get too high cause the powerstroke doesn't comsume all the fuel, so it continues burning down the pipe. Too rich also fouls up top ends and exhaust tracts.

[@garrisonsmith3186]

Could you do a video on rejecting a carborator? (Uses the old one)

[@thomasmorehouse9277]

hey fearless i got a 25 horse power Briggs and stratton engine, would have any idea why it back fries while running it runs good and drives it just back fires after like 5 mins of riding

[@cameronlupachino1527]

Not exactly sure but I think that means that you need to rejet your carb

[@thomasmorehouse9277]

Well hopefully fearless with reply and let me knpw

[@thomasmorehouse9277]

Know

[@preston121068]

Hey Thomas, I had a similar problem on 2 different occasions with 2 completely different solutions. Try one of these: First check what kind of gas your using. More and more we are seeing a number rating at gas pumps increasing the "E" rating. The "E" rating is the amount of alcohol mixture in the fuel. Example if you see on your local gas pump an E rating of E85, this means it is 85% alcohol and 15% gas. Some fuel companies are cleaning house withe inflated fuel prices by setting mixtures that high and increasing profit margins because alcohol is MUCH cheaper than actual gas. Problem is, in small engines it causes them to run MUCH hotter than they are made for and can cause excessive backfiring. (Had this problem on an 18 HP B&S) Look for an E rating of E25 or less. Second thing is not as easy. Carb may need to be rejetted/rebuilt. But it's not as expensive or as hard as you might think. Hope this helps, and good luck!

[@thomasmorehouse9277]

the gas in my local gas station is either ethanol or supreme look up ethanol gas it has a gel substance in it when it sits i think ill start using supreme witch is ethanol free and has a higher octain level

[@DonovanBryant92]

picked up a 12.5 Briggs Flathead from the junkyard for 5 bucks and also got a 13.5 parts engine along with a 5 HP Flathead for 20 bucks so 25 bucks for all three engines not too bad hopefully the junkyard will get some better engines in soon that have better carbs on them

[@rickysexton9198]

What carb should I use on my 15.5 kohler engine

[@MrEdsster]

Nice mod.. Only one more thing to say.. TURBO

[@Skulljeep00]

What model was that Carb you chose again?

[@enniofolini8755]

Geez, thanks so much thats exactly what i need to know!!!

[@kiskiller3]

hey do you think i could use a 13hp honda crb on a 6.5hp ? i may try... it may be a little much...

[@worleyracingproductions1755]

kiskiller3 all you need is a gx390 adapter and the carb

[@truckerfarmboy]

Love the new mod keep up the good work

[@hannahayden8000]

@fearlessfront could u help me with my lawn mower

[@DaltonTk423]

Nice! Sadly I'm in California and we have a law I guess that prohibits any small engine shops from keeping old engines and carbs. I have been to at least 3 shops in my area trying to get a few parts for my motor and they all tell me the same thing...

[@johnwimbs2157]

Must be less on the climate to build an entire engine than replacing parts lol

[@johnhicks9529]

Okay the one on the left is original.& the far right is your newest one you picked up right. Now there's one thing that you'll need to do in order for that to work on your ridding lawnmower engine is the same style.,or AKA. Right spacer plate.& mounting gaskets to that carburetor is all. Cause if not it will continuously suck air.& leak fuel do to wrong spacer.& gaskets. Unless your engine carburetor mounting place on the engine has to have those same grooves.,or that right spacer plate.& gaskets in order to function properly with out the engine block pregrooved to match those carburetors. Although once again by using the spacer plate& gasket set for the spacer.& the engine mounting gaskets such as to the engine block spacer between gasket. Then the aircleaner., or breather box/ etc. Unit setup.

[@renzoku163]

The real question is how good is it going to do on Mudd run

[@paulg444]

you could port the smaller walbro?

[@tylerandrewhoneycutt8570]

How did you do that shifter set up? I would like to do that on mine

[@matthewbailey299]

i have the same mower and he just uses the stock shifter

[@rtabish]

there is only so much you can do with bolt-on mods. about time to pull the head for some chamber work and do some porting.around the valves. take advantage of the extra flow potential. have you ever gotten into the crankcase to see what the piston and crank bearings look like? this should answer your question about how long before she blows up. haha.

[@Fearlessfront]

HA, thats all been done to this motor. The head was milled .010, I ported the "eyebrow" on the block, as well as all the intake and exhaust ports and manifolds. I also replaced the connecting rod and piston with OHV parts. I did all that about 7-8 years ago.

[@rtabish]

Fearlessfront any idea what you are running for compression? did you do any relief in the area between the valves and the cylinder?

[@Fearlessfront]

rtabish yea, thats the "eyebrow" I was referring too. Not sure on the compression.. a little more than stock. still uses the factory electric starter.

[@joeyheider9468]

do you notice much power difference, between having a governor opposed to not having one

[@coreyrobinson3314]

what town are you in fearlessfront

[@albertsewell878]

Good video. It would b cool next make some sort of exhaust with your mig and some pipe ( if a custom exhaust would help a motor like that)

[@bamataz13]

He already has custom exhaust I believe I thinks it's straight pipe

[@albertsewell878]

Yeah, I noticed and it prob wouldn't do anything to make some crazy exhaust but to maybe port the head and step up pipe size then use 17 hp or better muffler ,, just to see what cool sound u get or make it quiet.

[@brentkudla9086]

Well Done FF!

[@FrancoTheBoss3434]

Can you make a vid of reviewing and starting the craftsman crawler PLZ!!!

[@jeremyharmon1]

When/If you blow it, What will you replace it with?

[@Fearlessfront]

I donno, maybe an OHV... not sure. I love these flatheads.

[@nomajhondeere3324]

You should do a test how much HP at the wheels on the muery

[@DonovanBryant92]

i have a Briggs push mower engine that i have been rebuilding for about a year i want to put a bunch of performance mods on it and put it on a racing mower

[@camluckie4268]

When's the next romp?

[@rarbaugh07]

Since you got the track built and your pushing it harder you should get a billet connecting rod for a little insurance.

[@Fearlessfront]

ya, I'd like to do another full motor rebuild sometime.

[@albertsewell878]

If you do , make a video of that

[@superagricoltura]

Fearlessfront How did you supercharge the engine ?

[@JaySinsGarage]

erri silvagni He didn't, it's a snorkel mod so he can go through deep water and not get it in the intake.

[@jezoffilth2868]

What model of Walbro carb is this?

[@LIMowersAndMore]

the v twin carbs won't work?

[@rylanfrye8130]

Fearless were did u get your rain cap

[@Fearlessfront]

tractor supply co. Look online, the have a website

[@starpuss]

I would install a mikuni vm24-28 carburetor on her :)

[@MajorHorstPower]

Howdy, would one of those bolt on to an intake tube from a briggs? Or would an adapter plate need to be fabricated?

[@starpuss]

Custom intake would be best. or adapter plate would be quicker.

[@MajorHorstPower]

Cool. That's what I was thinking. I might have to try this idea out at some point in time!

[@starpuss]

I am looking at a TM38 for my Vtwin :)

[@austinstrickland7918]

u got somethin going on there in the garage with mud kings mower.

[@allenmckinney9533]

you can get certain carbs for $10-20 new on ebay.

[@slimjim119]

run great great video

[@slimline65]

Good job nice tip

[@joeormsby8451]

What's it take to blow ones ungoverned motor besides dragracing

[@MotivatedMetalworks]

Turbo! :D

[@DCopp]

U should've mic'd the inlet and outlet diameters.

[@collinbibeau1339]

Briggs and stations are bullet proof like a 4.0 in a jeep

[@knighthawk86855]

I like ....awesome idea!!!!

[@zach12s]

where do u get the pulleys to pulley swap

[@CountryBoyAdventures]

tractor supply or rural king has them.tractor supply has great exchange policy with belts also.and they have kevlar belts.

[@5.43v]

Country Boy Adventures How many rural kings are there?

[@gergemall]

Man that's cool !!

[@corbinnelson907]

Do a vid on the sidexside

[@enniofolini8755]

what machine can i find a 17hp briggs on?

[@Fearlessfront]

polan pro 17hp OHV

[@armankordi]

look like my little Datsun carburetors haha

[@rileymayo7519]

What is with the wrenches on the bumper?

[@steven481000]

hood mounts it looks like.

[@matthewbailey299]

they are hood mounts. he used them for a quick remove hood

[@Fearlessfront]

steven chamberlin Yup!

[@ricardomaya510]

great chanel

[@snickerstorino]

sweet

[@redneckbryon]

Not bad

[@ethanOneToxicRedneckcarter]

The cut out is ventilation not much to do with the idle circut

[@hellohun7331]

Carbs, as mechanical as they are, must be super clean, not corroded and not bolted on in the mud.

[@wills224]

i have a feeling that the engine is not going to take all that power for long.

[@buckyrichardsonii2533]

You lost me on “moving too much air and needing more fuel to accommodate for that air” with your air filter, if you were boosted youd need more fuel but you’re pulling in the same cfm with or without the “high flow intake “