Briggs & Stratton 12hp engine teardown with repair tips

[@cdogg1787]

"said nah I'll fix it." this is the level of confidence I aspire to achieve

[@BigOvlogger]

A great video Kenny! Two thumbs up from Kingsport, Tennessee!

[@seriksson9721]

A hell of a noise when you drop bolts and tools on the work surface, a rubber mat or some other softer material would have muffled the sound so we would have had an even better experience. Very good film by the way, thank you very much.

[@Misozeiej]

Bro thank you for the video it helped so much i háve the same engine and it just broke and now i know what i need to buy

[@kennytheguitarfanatic054]

Glad I could help.

[@ياسرريانلصيانهوتصليحجميعانواعا]

❤

[@jasonmayne1]

I’ve got a 12hp just like that and only getting 18psi compression. Going to replace the head gasket but don’t visually see anything wrong. Was hard to start, now finally won’t start. Any suggestions on what could cause low compression? I don’t know how to adjust (or get to) the valves and they don’t seem to be any KZbin videos on this. Thanks, Jason

[@kennytheguitarfanatic054]

Does the compression come up if you put some oil in the spark plug hole? If compression comes up alot the rings are bad. If the head gasket is fine and cylinder bore is fine. I would look at the valves. On the valves the gap on the valve stem to tappet clearance should be about .009 on the intake and the exhaust is .011. But the clearance usually don't change unless you put new valves in I would check the valve seats see if they are loose.

[@jasonmayne1]

Thanks for the reply; finally got around to working on it over the holidays. Oil in spark plug hole did not increase psi. Removed head gasket; valves seem to sit fine and cleaned the surfaces with a sponge so I didn’t break anything. They don’t seem to turn much when seated, so that seems good? Put new head gasket and torqued to 100 in pounds, again got 18psi like before. Going to try to open up valve tappets chamber and check clearances next. Thank you for the advice! Jason

[@Mike-su8si]

It could also have old build up around the valve seating I've seen it before

[@DeutschlandLife]

Hi there! Maybe you know what is causing the knocking of my briggs & stratton 11HP 253707 Engine. I uploaded a video on my Channel. I will tear it down, but maybe you have an idea what my problem is. Thanks!!!!

[@donald4416]

One number one build mistake Briggs did in those years was aluminum case with stupid metal ring insert for valves to seat for head, after enough run time on engine over year or two valve ring comes loose pops out it insert hole and engine stops, I find only way too repair this problem is to peen the ring back in with punch and or bit J B.Weld and hope for best to last mine still running after the fix.

[@nathanwelch2082]

What size bolt does the crankshaft use? Got my 12hp in my mower and lost the bolt apparently.

[@lovesbeer9973]

I have that same motor and its spewing oil from the bottom. I'm guessing a seal let loose. Any advice? I'm in NJ. I've had this tractor since 1999 and I'd had to throw it out. Its old and owe my nothing, but I'm attached to it.

[@Mike-su8si]

Would that piece fit the i/c briggs model of that same engine

[@kennytheguitarfanatic054]

if you mean the cam no ohv motors are different.

[@Mike-su8si]

@@kennytheguitarfanatic054 i know the ohv engines are different. But the piece you showed i was asking if it would fit the old model of i/c briggs 12 hp engine or any part off yours to mine I also have a old 8 hp briggs pull cord is broken it has a spot for a starter but i don't know what size starter it would take. But whats the difference between the 12 hp briggs and the i/c 12 hp briggs

[@kennytheguitarfanatic054]

@@Mike-su8si The difference with i/c 12hp and 12hp briggs is. The i/c briggs has a cast iron sleeve and aluminum piston. Were the 12hp briggs has aluminum bore and chrome plated piston the pistons are hard to fit they don't make them any more. Were the I/C briggs I believe they don't make OEM but you can get aftermarket pistons.

[@wesleemiller]

I need gaskets for mine but I don't know where to get the part number for the engine. Can you help me❓

[@kennytheguitarfanatic054]

It should be on the side of the engine. But if the numbers are rusted off The engine numbers that work on that type of briggs 12hp engine for parts .the model 281707 the type 0137-01 code 87010611. Hope this helps

[@victoryfirst2878]

The model 28 OHV Briggs connecting rod, the heavy duty rod you said you put into a 11 HP bolens. What was the engine make ??? Thanks

[@kennytheguitarfanatic054]

Briggs and Stratton 25 cubic inch 11hp The model 28 is 28 cubic inch.

[@victoryfirst2878]

@@kennytheguitarfanatic054 Thanks for clearing that up Kenny.

[@omarderder22]

very nice engine but the problem how to fix inside the boat the crankcase no have 4 wholes

[@luvbgrass]

Great video. I have a 12.5 BS on a wood splitter that is 20-25 years old. Motor has been great, but about every other year I have to order the plastic dogs and other parts for the starter mechanism on top. They are junk I think, and break bad. I would like a better fix for it. Would you have any recommendations. Sometimes it kicks back when trying to start, especially when its cold. I guess that could be some of the problem. I was told to adjust the valves by a friend. I haven't did that yet. Thanks

[@kennytheguitarfanatic054]

Kick back could be a slightly sheared flywheel keyway.

[@luvbgrass]

@@kennytheguitarfanatic054 Ok thanks. I guess I would just pull off the flywheel to check that, and replace it if so. Hadn't heard that one yet.

[@philliphall5198]

Every five years valve lash needs to be adjusted On ohv it’s nearly every year

[@luvbgrass]

I did check the valves after my post. They were in spec. Almost perfect, so I never moved the valves at all. Thanks, EE

[@cdogg1787]

you could convert it to a pull start. kzbin.info/www/bejne/eZ2ppKR7pdyihas

[@Mike-su8si]

Now see other people didn't mention about any worn lobes on the camshaft you did and i have because on my 18hp intek engine its lobes on the camshaft were worn down enough while the compression release was still good wasn't broken it all just worn lobes was my problem Now if the lobes were replaceable I'd do that and still use my old camshaft with its good compression release so after taking my camshaft out i compared the two together to see what the difference was and seen it But the videos on those focus on the compression release on the camshaft instead of pointing out it could be worn lobes as mine were worn. I dont think a valve adjustment on one with worn lobes would do much good anyways then the only way i figure the top lobe which actually was the bottom lobe was worn more than the top is because someone had already done a bad valve adjustment job on the engine

[@wrench]

Hello, love the video have gained lots of info. I aquired a 13 horse and it has been sitting a while. There is little rust on the cam lobes, is there any way to buff it or should i go ahead with an oem cam? Would like a second opion from someone else. Thank You

[@kennytheguitarfanatic054]

You can lightly sand the cam lobes as long as the rust is not to bad.

[@wrench]

@@kennytheguitarfanatic054 its not that bad, any reccomended grit to use?

[@kennytheguitarfanatic054]

@@wrench 320 grit

[@jeffc8591]

What is the model # for this engine. I have the same one and can't find it anywhere. Thank you

[@kennytheguitarfanatic054]

It is a 28 cubic inch engine or model 28

[@xx3868]

Hi i have old 12.5 Briggs with side plate Gov that seems ok and smooth running and loose when idle throttle then tight at full throttle BUT i can only get 1/2 power and push throttle further and no change. So does this mean the govt arm has slipped a little in that clamp OR the govt spring needs adj- and how? If i move the Gov arm myself, i get full power so its not moving far enough through that spring? thanks

[@kennytheguitarfanatic054]

If you look at the throttle bracket were the gov spring hooks on you can bend that to give you more spring tension .

[@xx3868]

@@kennytheguitarfanatic054 Yes thanks, another mechanic replyer said to back that spring off! haha No, you need to tighten it!! to get more rpm at same throttle setting. I watched another channel using diagrams how it works and its very simply as that spring just puts a biased over those weights and more pressure and it sets the rpm higher as the weights then balance. I will also check that spindle that it hasnt turned a bit and get it all correct as last owned made a bit of a mess of the valves and this and that so good to take it back to "specs" thanks for reply.

[@SuperWatha]

Can anyone send a link where we can buy these parts. I have to rebuild my engine 😩

[@kevintanner5307]

Yeah I got to love them old Britain Stratton engine good job oh buddy

[@kennytheguitarfanatic054]

Those old briggs motor are good i rebuilt this motor and have it running

[@billdozier6991]

I have a two cilinder B & S engine on an older Craftsman rider. If I remove the spark plugs I can rotate the engine 1 1/2 turns in either direction to a top dead center piston position and the engine jams up. Would this likely be a problen in the cilindar head or in the lower end. I had just replaced the caboretor and the engine ran well before that. I would rathe avoid a teardown if possible . Thanks.

[@kennytheguitarfanatic054]

Maybe you have a valve issue were the keeper came off and the valve is hitting the head rare but sometimes happens. Pull the cylinder heads to see. Or maybe one of the screws that hold the carb butterfly came out and the piston is hitting that.

[@drewa4235]

You had the box in your hand for the upgraded connecting rod. Why didn’t you just show the part number rather than giving generic info about a model 28.

[@SF004]

I was wondering why my briggs and stratton engine valve hits the spark plug? I replaced the piston rod. Put everything back together but the top valve hits the spark plug. It's the same engine here, off a JD STX 38 Thank you

[@kennytheguitarfanatic054]

On that engine I believe it would be the intake valve check the valve spring maybe the keeper slid out slightly or lots of carbon on the valve stems they can stick sometimes. Or could you have too long of a spark plug The correct spark plug should be a champion number RJ19LM.

[@SF004]

@@kennytheguitarfanatic054 thank you! Appreciate the feedback. Will check all those things.

[@kingoftheput]

What is engine code for this motor? I can't find number anywhere,but my engine looks the same. I need to order piston rings

[@kennytheguitarfanatic054]

If you look on the shroud the side the spark plug is the numbers should be above the two 7/16 screws are . Or just look up briggs 12hp model 28 which is 28 cubic inch. The stock piston ring number is 499996.

[@ronaldjohnson1474]

Damn, your disregard for your tools is painful to watch!

[@philliphall5198]

I use my very old bs fly wheel puller but can do it several ways

[@MrRenoman2011]

Great video. Can the synchro balance issue cause a bad vibration?

[@kennytheguitarfanatic054]

The synchro balance would have to be very worn and noisy to vibrate. What engine do you have.

[@philliphall5198]

It will run again and last a long time New piston and rod 😊rings valve job 😊😊😊

[@bennockley]

Good OnYa , Ken, Bloody Good Vid Mate, Ya Saved Meh!!!!! :-) ;-)

[@tomjk64]

Badly day for KZbin video , your work partner is noisy in the background 🤔

[@rsz90182]

Brigzz-n-scranton!

[@amandagardner565]

wtf the audio is out of synch with the video. at 6:49 the audio mentions the timing marks lining up, but the video showing the timing marks is at 9:40.

[@kennytheguitarfanatic054]

Thanks for the notice I noticed some of my videos are doing that but I fixed the video.

[@buddyd.irishsr.5646]

As soon as you took off the flywheel you should have took the alternator off or the windings. The way he's throwing that motor around he'll wreck the windings on the alternator that which is underneath the flywheel

[@athannaelanderson3806]

It’s called a magneto FYI

[@buddyd.irishsr.5646]

@@athannaelanderson3806 thank you, now correct the other so many videos that call it an armature or alternator, it puts out ac volts and the regulator turns it to dc. But thanks for correcting one person among many, feel special!!!

[@athannaelanderson3806]

@@buddyd.irishsr.5646 If you want to be vague, they are all called electrical generators, I don’t have time to explain the tiny differences in definition. Your welcome 🙏