Briggs and Stratton 3.5 HP Dies or Surges - How to Fix 

I read somewhere that a manufacturer flaw of the tank is the area the gasket touches tends to prematurely not seat correctly. A guy a couple years back suggested taking a scribe or sharp tool and scratching a line on a specific area of the tank (can't recall exact area) which allows the gasket to have something to bite into when put back together. Great video!

Very good instructions. I just fixed a mower with a surging problem.

Thanks for this. Ive got a 35 year old Yard King with one of these engines, I remember my Dad using it when I was a kid! Its started cutting out when hot so will sort all of these issues out.

Thanks, just stripped ours and now running fine 😁 gunk in the bottom of the tank. Good clean out thanks to old rotten fuel

Bought my crappy NOT. Tecumseh 3.5 24in deck back in 1993. dont have a big lawn changed out the oil every season 10w 30 synthetic. 25 years later I intentionally let my grass get at least 5 in high give this puppy a hot supper.This thing other than the fact the deck has held up my grandchildren will be using it.Run it out of 91 octane treated with fuel stabilizer every season. still starts one pull every season.Not shitting you one pull.Anyways my point is look after your small engine and it will give you many years of service. My take on longevity of a small engine.1 Run the puppy on 91 octane has little to none ethanol. Ethanol is hydroscopic it attracts water screws up a small engine carb. Thats why the pefectly running small engine the season before wont start or runs badly. Ethanol is the best thing that is giving small engine shops jobs. 2 treat your fuel with stabilizer .3 totaly run your small engine out of fuel every season no really use a syphon pump to get rid of the bulk of gas in the tank run the engine till it stalls dump the fuel in your car and burn it the cars fuel tank volume even at one quarter not going to care.Even noticed a little more pep from this treated fuel . 4 pull the start chord until you feel resistance and stop you have effectively sealed the cylinder. This engine is now put to bed. Licensed 310 s and 310 t in Canada car and coach. Work at a Freightliner dealership small engines are my hobby and passion. 1 cylinder engines i can repair and lift into my workbench. Love that my colleagues dont have a clue. Cant figure out why the weed trimmer wont idle or start. Its old school its carburetors 99 percent why a small engine does not perform.These dudes were going into the field when fuel injection was the norm. Anyways blessed born in 1966 saw the infancy of fuel injection in the 80s still have a grip on carburetors. Follow the tips and you will be starting your small engine 20 plus years on the first pull.

Fixed mine permanently by throwing away the plastic crap carburetor with a 70’s 3.5 hp all metal with old style intake manifold and governor plate. Gave an adjustable reliable machine which had started with two pulls for 15 years.

hey man thanks for the video, the gasket i had was no good and replaced it and now shes working again mine was a 4hp one but it all worked the same

I thought gasoline was already wet. LOL that was a good one. You said to run your mower all the way out of gas so your gas doesn't set in the tank and get wet.😁

I put paper tape on the carb's sealing area closest to the block, it fixed the leaking gasket surging problem. BTW - The appearance of oil around that area is from the gas, a hint it's a leaking gasket.

Thanks! That was awesome Dude, my lawnmower is running like CHAMP now.

Wow. Thank you. Very helpful and easy to understand.

Covers a lot and clearly explained thx.

Thanks. Great video. Very helpful.

It would have been most helpful to have a Gasket Kit Part number listed. I have the exact same carb on a Murray Classic 20"

I fixed my Briggs and stratton with a 12 gauge slug!

I'll try this tonight thanks . Mine just loss all power while mowing.

How do you clean the fuel tank please

great video ty

You didn't mention the filter screen at the end of the pick up tube

why do you use metric sockets on standard bolt heads

I just got a free one just like that and I got it running

Replace the carburetor. Tune the engine. Check leakdown to check rings, valves, and head gasket. Check the blade. Replace the top and bottom oil seals. Replace the govonor spring. It stretches. Tighten the head bolts. Brigg has valve guide tools. Install new valve guides.

The "gasket" is NOT de-laminated... those are two separate pieces...a gasket and a diaphragm. There are far better videos on YT that demonstrate the whole process including reassembly...

I currently have the problem where it will surge and back fire but I don't plan on fixing it any time soon because it still cuts and if need be i will put carb cleaner though it

I've got a 5 hp Briggs on a tiller. I was tilling up the garden and noticed something laying in the dirt. It was the breather tube. About the time I picked it up the motor shut off. I cleaned the tube, put it back on and now she wont run right, surging and cutting off. I've cleaned the carb, checked fuel lines, changed the spark plug, cleaned the gas tank and new gas. I just cant get it right! I'm trying to get a fall garden ready for a market garden and I'm running out of time. Please help!

If it still doesn't run right after replacing the diaphragm, try using 2 gaskets with the diaphragm sandwiched between them. That's what finally worked for me. I saw this trick here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8lyJka9XU58.html

Did all this... And it started up and was going great for about 10 mins....then stopped dead... Can't get it to start again! 15 years old... Maybe time for a new one?

Awesome video! I changed my throttle/governor linkage to a fixed position setup with some thin gauge wire I had. I did this because when I got the mower the springs were missing. The mower seems to work fine this way. Are there any downfalls to this setup that you can think of? I don’t think that it will rev up under load anymore but that’s okay with me. Will it affect anything else ?

Hi mine pops while running, cleaned the carb and replaced the gaskets still the same

I have the exact same engine. I would start and run for a minute and then die. Now I have cleaned the carburator. Installed new diaphram and air filter. Now it won't even start. The button does not seem to pump fuel anymore. I disassembled it again and tried the pump while the long thing was stuck in a glass of water. No effect. What could have gone wrong?

I have the briggs and stratton 500 series engine on my Murray pressure washer. I just cleaned the heck out of my carb, replaced the carb gasket+diaphragm+primer bulb, new spark plug and air filter. But It's still acting like it's not getting fuel... I can prime it a bunch of times and it will fire up for a few seconds and then dies. I made sure I installed the gasket + diaphragm correctly (diaphragm on tank first then gasket). Linkages holding throttle wide open when it's running but it still dies. Fuel is fresh and no debris in tank. I'm kind of confused at this point as to what it would be any suggestions?

Part and motor info please. I'm having a hard time finding parts including kill cable.

I wouldn't advise anyone to use this video if they want their machine to last.

good tear down, but thought you was going to show the skill of cleaning and repair.

Put the camera a little closer to what your doing i cant see what your doing

My 3.5 murry is using more fuel than normal

mine surges until i loosen the gas cap...

A mate it’s got no wheels on back so why repair

You are not making much sense Why would you soak the gaskets Those need to be replaced. If people follow your crazy advice they will be spinning in circles.

use only NON ETHANOL GAS this causes 99 percent of small engine problems

Too much yap and no action. The plastic carburetor comes apart,.....you can clean the jets,.........most people don't know that the o-ring is kept in place by a snap-ring and that you should always replace the diaphram and gasket,....... get some marble sizes river stones fill 1/3 of your tank and add white vinegar and shake it back and forth. And like Taryl Dactile says and there's your dinner.

Them bring are junk .

worst briggs engine ever

Thanks for video!