Briggs 4hp 187cc model 112292 0707 -- rebuild, need advice!

[BubbyJ]

I posted this is the wrong forum the first time. I apologize for that.

I have a Briggs and Stratton 4hp 187cc engine. It was pulled off of an old wood and leaf chipper. I'm unsure of its age, but I'd venture to guess that it's from between 1970-1980. Could be either side of that by a decade too lol, I honestly don't know. The model number is 112292 0707. I'm not sure if that helps anything, but all I've found is the operating manual online for it. I'm guessing it's pretty old just because it's only 4hp with almost 200cc. That's a pretty low number for an engine that size.

So here's the story...

I've been building automobile engines for the last 25 years, specializing in blueprinted "stock" engines from the 1960s and early 70s. So I don't really need much help in terms of rebuilding this thing. My 11 year old son is following in my footsteps and learning so much so fast that it's scary. He wants his own small block ford engine to build. I dug this old motor up recently for him to strip down and rebuild. He has a gokart frame that he wants to test it out on when we are done. So what I do need help with is this:

-where can I find a parts interchange list?
-suppose I wanted to install a more aggressive camshaft, where would I find the type of camshaft that's made for this engine? I'm assuming not all BS engines use the same cam type. Correct? Is there's a series or an engine design name for this motor that would allow me to identify parts better? For instance, small block Chevy. Pretty much any sbc part will fit any sbc engine (with exceptions). Same goes for 385 series Ford's. Or big block Pontiacs. Or FE engines.

So.. what am I looking for as I order a few parts for this engine, so that I know what I'm getting is correct for the model.

Thanks so much. This means the world to us. He's an incredible kid with big dreams and strong desire to learn with tons of motivation in action. During this crisis we find ourselves in, family means more to me than ever before. Im hoping that a couple of weeks from now, I'll have a 7-8hp engine for this kid to drifft around the yard in.

I see tons of parts for Briggs motors. Cams, billet cranks, high compression pistons, ported heads, straight exhaust, adjustable timing, etc. I had no clue that this world existed until the last few days.

If I'm in the wrong forum for these type of questions, can someone please direct to to where I can find the right people?

God bless yall. Stay safe please.

 

[Romore]

The next seies of numbers gives the manufacturing date. For instance 730407 would indicate 1973, fourth month, seventh day. You won't find off the shelf hot rod parts for it. Briggs does or at least did build racing engines but they are only sold through specialized dealers affiliated with accredited tracks.

 

[jp1961]

Hello,

You probably wouldn't get a lot of power from the flathead Brigs. I'd walk through a rebuild with your son (using stock parts, if needed), then look for a more powerful engine for later. Weren't the "hot" engines for karts a Mac9 (short for McCulloch)?

Regards

Jeff

 

[logert gogert]

i was at the point one time where your son is. i wanted to put one of my 6.5 hp B&S engines on a gokart frame i had laying around, and i wanted to get some parts for it, ( billet flywheel & rods ) and i found a few parts, but not as many as you would think....
but if any body were to have any performance parts for that engine i have to say it would either be:
arc racing: ARCRacing.com | ARC Racing | High Performance Engine Parts‎Ad·www.arcracing.com/Engine/Parts‎(877) 210-7019
gopowersports: https://www.gopowersports.com/front-page
or precision cams: Precision Cams Homewww.precisioncams.com


or if you want to be on a forum where people do that stuff to small engines all the time ( the websites kind of like this its just....different..i can't really explain it ), I'm also a member on the website.
they are great people and would be happy to awnser all your questions.
heres the link : https://www.atltf.com/forum
all you have to do is sign in ( like your did with this website ), then create a thread on the questions you have, and then wait for responses.

 

[Hammermechanicman]

Hello,

You probably wouldn't get a lot of power from the flathead Brigs. I'd walk through a rebuild with your son (using stock parts, if needed), then look for a more powerful engine for later. Weren't the "hot" engines for karts a Mac9 (short for McCulloch)?

Regards

Jeff

The MAC101 was the hot motor. But that was a looooooonnnng. Time ago.

 

[Hammermechanicman]

The next seies of numbers gives the manufacturing date. For instance 730407 would indicate 1973, fourth month, seventh day. You won't find off the shelf hot rod parts for it. Briggs does or at least did build racing engines but they are only sold through specialized dealers affiliated with accredited tracks.

Briggs built the Raptor motor from 1991 to 1999. Built specifically for WKA kart racing. The engine had no more power than a stock 5hp. It was built stouter with better valve guides, con rod, head gasket and bolts and stronger gas tank mount. Cam was same as stock 5hp to meet WKA rules. If you can find a Raptor that is not ragged out they are good motors. Anybody could buy a Raptor from a Briggs Motorsports dealer.

 

[tom3]

The easy way out would be to visit the local Harbor Freight and get a Predator engine for the kart. Not as much fun as building a motor though. I've had pretty good luck finding NOS parts on Ebay for old Briggs motors. Search your engine number for a parts list and spend some time on there. Find some real bargains if you're patient. I tore down a B&S motor back when I was about 10 years old, tightened the rod and new rings, it actually ran ok for years, real good learning experience.

 

[logert gogert]

Predator 212 NOS Nitrous Kit$69.50WalmartFree shipping
:3 XD

 

[FlatheadsForever87]

I have one of these 4hps as well very strange engine if you ask me. But I think its gonna be a lil torque monster. Whats odd about these are the bore is quite a bit larger than a 5 hp but with a significantly shorter stroke. Also another perk in my opinion is the connecting rod is unlike any of its "smallblock" family from 2 throughat least 5. Instead of the traditional straight up and down con rod it has one that closely resembles a rod inside a Honda ohv. Odd but interesting. Only thing so far tht can be cross used on a 5 hp is the crank case cover.. As far as finding performance parts for a flathead I would suggest getting a 5hp. Limitless performance upgrades and honestly probably a better power plant all around. For your sons sake I would introduce him to the forum called Bob's 4 cycle. Very fine folks on there with more knowledge and advice than a youngans mind would care to absorb. Also like to point out a false fact, briggs performance/ racing parts are not only linked to certain tracks. Anyone at anytime can buy in to them for their own back yard.hope this helps and hope to see you soon on Bob's4cycle.com

 

[tom3]

If you're still into the old Briggs a couple things you can do for free. Pull the head, some sandpaper on a flat piece of steel. Plane (cut) the surface down as much as you can and still have a good gasket surface. Find a bigger carb on something in a scrap yard, make it work since you don't need the governor. There are slapper cams for the Raptors, same basic motor? Probably not suitable for a yard runner though.