I found a flathead in my garage.

[sparkwizard]

I want an engine for a project that my son and I are planning for this summer.
This engine is model number 130202. Can anybody tell me anything about it before I tear into it?
Like, aluminum or steel bore? Bearings on the crank? approximate age? I do not remember even putting it back in the corner of the garage.
edit: sorry ! Forgot to mention it is a Briggs horizontal shaft engine.

 

[Powerband83]

The blower housing (fan shroud) could have been changed for another housing and always assume so. The best way to tell what you have, is to pop the sump cover and head to verify. Put a magnet on the top of cylinder to see if it's a steel bore. Once you pop the sump, you'll see a bushing or ball bearing. If it's got a bearing, steel sleeve and an oil sensor, it is a factory I/C engine...which makes for a great build candidate! I highly recommend buying a briggs manual for the future.

 

[creia]

How about some good photos?
If, (and that is a BIG "IF") the recoil shroud with that model # is original to that engine it is a 5HP aluminum bore, bushing block (i.e., no ball bearings). If you can provide the last sequence of digits of the engine number ("Code") we can tell you the year of manufacture. Ditto everything that Powerband83 stated especially about getting a Briggs repair/service manual.
Michael

 

[Bird Brain]

Il agree with Creia, it is all aluminum with a bushing side cover. I had one in the late 80s and appeared to have been 8 to 10 years old at that time. I bought it used for $35 dollars. Very robust engine. Great teaching/learning engine basics tool.

 

[Minimichael]

Il agree with Creia, it is all aluminum with a bushing side cover. I had one in the late 80s and appeared to have been 8 to 10 years old at that time. I bought it used for $35 dollars. Very robust engine. Great teaching/learning engine basics tool.

But is it still a fair candidate for upgrading? Worth buying the billet rod and flywheel for it?

 

[Powerband83]

But is it still a fair candidate for upgrading? Worth buying the billet rod and flywheel for it?

That very well depends on the person, money and end goal. I can't stress that enough...if it's for someone just trying to have fun with a little bit of billet (rod/flywheel) for safe measures, then by all means I genuinely approve!

A sleeved block is the go to...no secret there.
Bushing or bearing block are both great for any project/fun!
One valuable peice to building ANY 5hp flathead, always use a side cover that takes a bearing! (Heavy breathing)

Many years experience at hand and no disrespect to the novice.

 

[sparkwizard]

Thank you all for the information. It has good compression, we do not need a ton of power yet so we probably won't even take it apart.
Basically did not want to mess up a collector's item.

 

[sparkwizard]

Model 130202
Type 1033 02
Code 81120906
I believe that would make it December 9th,1981.
It looks to be all there except the air filter housing.
This will be a great engine for my 9 year old to get running.

 

[Harquebus]

Model 130202
Type 1033 02
Code 81120906
I believe that would make it December 9th,1981.
It looks to be all there except the air filter housing.
This will be a great engine for my 9 year old to get running.

Sure sounds like a venerable 5 horse B&S and a Dec 1981 model as you said.

The following page has a basic parts rundown of your engine series of 130202-1033-02-81120906 and a general rendition of what your engine may or may not actually have: Briggs 130202-1033-99

However, according to the Briggs & Stratton Numerical Number System yours is:
13 - Engine displacement in cubic inches
0 - Basic design series
2 - Horizontal shaft/Pulsa-Jet Carburetor/Pneumatic or mechanical governor
0 - Plain bearing/DU non-flange mount
2 - Rewind starter

And for everyone else:
A. First two digits, 81, indicate the calendar year, 1981
B. The second two digits, 12, indicate the calendar month, December
C. The third two digits, 09, indicate the calendar month, 9th day
D. The last two digits, 06, indicate the assembly line/manufacturing plant

Just a plain bearing block, sadly, but I would have no qualms about upping the ante with some performance parts but most serious flattie fans tend to put those parts on a Raptor or I/C (Industrial Commercial) version that has the iron cylinder sleeve and one or dual ball bearings.



Did you and your 9 year old get it running yet?

 

[sparkwizard]

We just got the carburetor yesterday. Workbench is cleared off. Engine is on the bench. We are planning to totally disassemble it, scrub everything and reassemble it with new gaskets. His last day of school is this Friday, so we have not really gotten serious about it yet.
I have been steadily moving tractors and equipment around so we have a clear, well lit area for this lesson.
The frame pieces that we have collected up are under the same bench. He wants to learn to weld this summer, too. This will not be a project that I can throw together without a lot of teaching time. He does seem excited to get started and he has shown me some drawings of what he thinks it should look like. He has been reminding me that we need some fresh BLUE paint.

 

[sparkwizard]

We also found a 4 horse engine missing all of the sheet metal. If we need any parts I think we can rob them from that donor. We have already decided to fill the old gas tank with vinegar to remove some powdery rust before we put a new carb on it.

 

[sparkwizard]

I got my new carb from Amazon. If will fit the block, but it doesn't fit the tank. I found a used tank locally, but now I need the little screws to connect the tank to the carb. They seem to be an odd size, since Lowe's didn't have anything to fit in the holes. I assume this is an Ebay part?
Also, I have read that putting an exhaust valve spring on the intake valve might help reduce valve float. I have a 4 horse sitting here. Our plan is to remove our valves, do a little porting and install that 4 horse spring on our 5 horse intake valve. Reasonable?

 

[Harquebus]

You should have posted photos of your engine, fuel tank and carburetor, because something seems wrong. Then again you have to know what you need and know what to order. Parts numbers are crucial.

There have been many a Briggs flathead engine building guide written on the internet, books written too (mostly for racing engines).
Valve float or flutter can be a desirable thing because it is its own engine rev limiter. At valve-float-RPM, the engine just cannot open and close the valves fast enough to go faster.

As far as porting goes, I have heard the "casting defects" in the intake port are beneficial for air/fuel atomization so little needs to be done, but there are benefits to porting the exhaust as timely exhaust gas evacuation is a good thing. Also consider "shaving the eyebrows" around the valves.

A good, general flathead rebuilding guide is one on YouTube by Taryl Fixes All. He rebuilds a Briggs 5 HP with some really neat tips and tricks but he doesn't do a perfect job or use all new parts (because he didn't need to). It's just an overhaul basically.

Your last plan sounds reasonable.

 

[creia]

Do NOT "port the exhaust" outlet on a Briggs 5HP flathead! On the 5Hp engines they are already oversized (a factory design defect). By enlarging the opening (even slightly) you will actually be reducing the performance.
Michael

 

[Harquebus]

As Powerband83 and creia already said, you could have a mismatch engine on your hands. If the blower cover is not original to the rest of the engine, the engine could be nearly anything or a much earlier motor. Who knows?

As for the carburetor screws, I don't know what size they are but they are fine-thread machine screws. In post #9 I put a link to Jack's Small Engines and the carburetor screws are listed as Briggs and Stratton 692200 so you can use those as search terms and see what you come up with. Another forum might have that info or a source for substitute screws--


Again, please post some pics. I don't know what you have exactly but I or another member could have stopped you wasting money on that carb that doesn't fit. We have the technology to post pics in 2023 and yet many fail to do that, and we end up basically blind, trying to lead another blind person out of a strange room with lots of furniture on the floor. . .

 

[Harquebus]

Do NOT "port the exhaust" outlet on a Briggs 5HP flathead! On the 5Hp engines they are already oversized (a factory design defect). By enlarging the opening (even slightly) you will actually be reducing the performance.
Michael

True. You cannot enlarge the diameter of the exhaust port or do anything radical without ruining it. If there is casting flash or a mold seam in there, you can remove it with a grinding bit and smooth it out a little but that's all I would do. You already have to contend with the valve stems in both ports (they're in the way) AND you risk damaging the valve guides if you go crazy with the grinder, and it's just not a high-flow style of head.

Overhead valve engines are where it's at and what you can really develop more power with.

 

[massacre]

Overhead valve engines are where it's at and what you can really develop more power with.

Yeah, all those slow jr dragsters goin 80+mph in the 1/8 mile in 500lb chassis lmfao

 

[sparkwizard]

My engine is a 130202 from 1981. It has the carb mounting holes both close to the center hole. The carb and tank that were in the box with it had one mounting hole about 3/8 of an inch lower than what fits the block. I found a carb on Ebay that fits the block. The two tubes under the new carb did not fit down into the newer model tank. Local small engine repair guy knew what tank I needed, so we took apart an old tiller he had out back. The screw heads were either broken off or stripped, so I welded nuts on them and removed the rest of the threaded parts. So, now, I need screws.
I have some pictures on an Amazon tablet but I use a desktop computer and I refuse to upload pictures to Amazon so I can access them on the home computer. I have not been able to figure out how to move images from the tablet directly to a remote hard drive attached to the computer. I have too much other stuff going on to take time to decipher all the security and permissions required to move my own pictures in my own home from one device to another device when I have a USB cable connecting them together. Fxxx Microsoft and Amazon!
I plan so shave the eyebrows, swap the 4 horse exhaust spring to the 5 horse intake valve, and install a thinner head gasket. I have one of the aluminum exhaust reducers still in the package. I got that from a member here last week. I am pretty sure I'm going to make or locate the linkage to connect the governor to the carb.
Thanks for all the advice!

Oh...I am well aware of the Predator power and price. This is for a reverse three wheeler yard kart for a 9 year old. I will probable end up with a baby predator 79 cc on this for a year or two. The Briggs is a nostalgia thing for the old Daddy.

 

[massacre]

Pretty sure if you become a supporting member, you can upload pics directly here to the site?
I use a hosting site such as imageshack and upload all my pics there. Then i can post pics wherever i want.
Trying to post pics without paying at least a small fee somewhere is pretty much impossible nowadays.
I'm glad you're keeping the flathead, i love flatheads

 

[sparkwizard]

They are getting hard to find. I was at the scrapyard last week looking for any flathead Briggs. I found a small edger with a 3.5 Tecumseh on it. Had a belt and a blade. I paid 20 dollars for it, changed the kinked fuel line , adjusted the carb and it started right up. My son said WOW lets use that engine! Wife saw it and WOW you got me an edger for my tea garden! Nice clean little flathead, too.