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The Engine Will Not Start
The pull cord is free to move, but the engine will not start
The Pull Cord Needs a Harder Tug
Small gas engines require human power to get going. Pulling the starter rope gets the piston moving and generates the electrical power to spark ignition. This requires a good amount of force so make sure that you put in a few consecutive strong tugs before assuming something is wrong. Check out a pull cord replacement.
The Fuel Tank is Empty / The Fuel is Bad
Lawn mower engines run on gasoline held in a small tank on the backside of the engine. Like cars, the engine will not start without fuel. Make sure there is fuel in the tank. Fuel that has been sitting for long periods of time can also go bad. Consider draining old fuel and refilling the tank with new gasoline.
The Spark Plug is Bad / The Spark Plug Needs Love
The spark plug is a cylindrical piece the size of your thumb that can be found on the front side of the engine. It is made of silver metal and white ceramic and is what ignites the fuel in the engine. Spark plugs will wear out after extended use so make sure to check it. The spark plug can also be disabled if it is unplugged, dirty or misaligned so make sure it is clean, plugged in to the black electrical lead, and screwed in tight. Check out a spark plug replacement.
The Air Filter is Clogged
The air filter can be found on the left side of the engine and is a consumable component. Air filters need to be replaced regularly and if clogged, will prevent engine start up. This is because the air filter provides clean air to the combustion chamber. If it is clogged, no air will reach the engine and it will not start. To replace the air filter, check out this guide.
The Fuel Filter is Clogged
The fuel filter cleans the gasoline on its way through the engine. If clogged, it will prevent fuel flow and the engine will not start.
Note: Sometimes the fuel line just needs a few taps to allow fuel to pass though. give this a try before taking your engine apart.
The Engine Stops in the Middle of Mowing
The engine starts up fine, but stops or seizes while mowing
The Fuel Tank is Empty / The Fuel is Bad
Lawn mower engines run on gasoline held in a small tank on the backside of the engine. Like cars, the engine will not start without fuel. Make sure there is fuel in the tank. Fuel that has been sitting for long periods of time can also go bad. Consider draining old fuel and refilling the tank with new gasoline.
There is No Oil / The Oil is Low
Oil is very important to any mechanical machine. It keeps the parts moving smoothly and without it, your engine can become sluggish or even seize up. You can check your oil level using the dipstick located on the inside of your oil cap. If the oil level is low, make sure to replace the oil before running the mower again. for help with this, check out this guide.
The Air Filter is Clogged
The air filter can be found on the left side of the engine and is a consumable component. Air filters need to be replaced regularly and if clogged, they will prevent the engine from running. This is because the air filter provides clean air to the combustion chamber. If it is clogged, no air will reach the engine and it will not run. To replace the air filter, check out this guide.
The Spark Plug is Dirty / The Spark Plug is Misaligned
The spark plug is a cylindrical piece the size of your thumb that can be found on the front side of the engine. It is made of silver metal and white ceramic and is what ignites the fuel in the engine. The spark plug can be disabled or fire irregularly if it is dirty or misaligned so make sure it is clean and screwed in tight. Check out a spark plug replacement.
The Engine is Smoking
The engine starts emitting smoke when turned on
There May Not be a Problem
Internal combustion engines like this lawnmower engine burn fuel to generate power. When the engine is first turned on, it is not uncommon for it to puff out white smoke until the system heats up.
The Oil is Leaking / The O-Ring has Failed
If the engine continues to smoke after extended use, or emits a dark colored smoke, you may have an oil problem. If oil is allowed to enter the combustion chamber, it will burn producing large quantities of smoke. This could be due to an oil leak somewhere in the engine or a failure of the o-rings surrounding the cylinder. Both of these issues are relatively serious but uncommon. Both would require repairs beyond the scope of the guides on this site.
The Engine Makes an Abnormally Loud and Unusual Noise
When the engine is turned on, it makes a noise unusual to the mower
The Muffler has Failed
The muffler, located on the left side of the engine, is responsible for lowering the volume of the outputted engine noise. It does this by sending the engine exhaust through a series of metal baffles that lower the energy of the gas. Over time, the muffler can become damaged by use and can fail to perform its function. If this happens, you can replace the muffler using this guide.
General Maintenance Problems
Gas engines have many moving parts and produce a lot of mechanical vibrations when running. If your engine is making a strange sound such as a rattle or squeak, do a general check of the engines components. Check the oil level to make sure it has enough lubrication, check the bolts that hold the engine in place to make sure they are tight and check the spark plug to make sure it is in the proper position. General maintenance problems could cause abnormal vibration or friction that can be audible.
Team
Cal Poly, Team 6-31, Amido Winter 2015 Member of Cal Poly, Team 6-31, Amido Winter 2015
CPSU-AMIDO-W15S6G31
4 Members
14 Guides authored
40 Comments
Front tires are not pulling.
fairlane64 - Reply
front tires are not pulling, belt is connected and turning when motor is running.
fairlane64 - Reply
turned it up side down (the lower half - the mower ) and dark blaskish opil spilled out of it. how to replace refill the oil ? there's no manual for this .
gothic81 - Reply
my briggs & stratton 675 engine series takes a while to start up and when it does start up the engine is weak how can i fix this
Austin - Reply
mine too! seems as if fuel supply issues…doesn’t sound as if full power ..
francis.samuelson -
when i took it apart i found that my fuel intake valve wasnt moving and my engine had no compression
Austin - Reply
Briggs & Stratton 675EXi troubleshooter Air cleaner cartridge got dirty
My Air Cleaner & cover flew off my mower & I crushed the air cleaner... finished mowing just fine.. Replaced the air cleaner... cleaning out inside the two small holes... Now the engine won't start!!
HELP!!
Betty Johnson - Reply
My 675 exi ‘hunts’. what I mean is the revs drop & come back continually every 10 seconds or so. There doesn’t seem to be a fuel filter on it ad the air filter is new. Any ideas?
Dave Toner - Reply
I used the mower Friday. Sunday it wouldnt start. I changed the air filter, spark plug, oil and cleaned the carburetor. Still it wont start. Any idea?
jonahlesperance - Reply
I have a 675 Troy-Bilt engine that died in the middle of pressure washing. It doesn’t appear to be seized, the cord pulls easily. The engine makes a hissing sound that I don’t remember being there when I pull the cord. Could it be that I blew a gasket or is a valve stuck open?
bryrowell - Reply
will run for just a min and stop.
Rickey Carson - Reply
Hi Rickey, did anyone answer you? I have the same problem. It starts, runs 5 seconds and stops. It will only start again if I prime it, and it does the same thing.
davidfairchild53 -
First, pinch off the fuel line running to the carb to stop gas leakage. Loosen the bolt under the carburetor bowl and carefully remove the bowl. Clean any foreign matter from the bowl. Check the O-ring that is between the bowl and carburetor and if it’s dry and brittle replace. Finally, and very importantly, use a very small wire and clean the holes in the bolt that secures the bowl to the carburetor then carefully use compressed air to blow in the threaded end. Air should escape both sides of the bolt. Carefully replace all parts and start you engine.
Buggs Clark -
the circle disk that holds the blades fell of
Morgan Swann - Reply
How to put back on briggs stratton 675
Morgan Swann - Reply
675 exi163cc ohv only year old wont start, has no compression when you pull the rope
Arnold - Reply
one year old Poulan Pro 675EXI 163cc ohc won’t start. Has no compression. May 16 2019
Arnold - Reply
I have a briggs and stratton 675 mower. It will not atart up. I've drained the old gas and put in fresh but it still wont start. I found this web page to help me but it has a guide to every problem except the fule filter. Will someone please tell me where the fule filter is located and tell me if this could be the problem..My grass is getting high and i need help..
Jacksoncarl40@yahoo.com - Reply
I have a Toro 675 GTS recycler 55cm. I changed the spark plug, the air filter and fresh petrol. It won’t start with the switch but it start with pulling.
cageorgio - Reply
my briggs & Stratton 675ex engine won’t start pull on cord engine spins over but won’t start . spits out carburetor. cannot find the problem.
Ray Madden - Reply
The belt located underside came off, where and how do I put it back?
carmencita oliva - Reply
It’s a Briggs & Stratton 675 model, I was cleaning the underside and the belt came off.
carmencita oliva - Reply
when screwing the blade bolt on the screw hole looks as though a piece has broken off. What is that assembly called that the blade screws in to.??
garydonsmith47 - Reply
My mower will not start again after it is warm. I have to let it cool down before it will start again. What could cause this? It starts easily when it is cool.
paperloader2001 - Reply
My B&S Series 675 starts great when cold, but if I turn it off when hot, it will not start util it cools down. Was wondering if the ignition coil could be causing this problem? Any ideas?
Rick Wilmont - Reply
i have the same problem cant figure it out
Tom Maddux -
When I start the engine it over rev and can not be controlled by the throttle. It appears the governor is not functioning inside the engine. Does anyone know how to fix this problem.
Ash Gregg - Reply
new fuel, cranks with starting fluid pulled carb and cleaned needle and seat ?
steve - Reply
Runs for just a few seconds when using starter fluid
Eugene Reese - Reply
New gas, changed fuel filter, will run for about a second when using starter
Eugene Reese - Reply
My briggs&stratton 675 engine is only 3 months old and its not running because fuel problem
boogieat6 - Reply
My briggs&stratton engine wont crank its not getting fuel ihave cleaned the fuel tank put fresh gas in it still wont crank its only 3 months old it will crank on starting fluid then cuts off
boogieat6 - Reply
Hello there, I’m wondering if you could help with a problem with my 21” Troy Bilt (Briggs & Stratton 190cc) series 675 self-prop lawn mower.
-Purchased around 2008
Problem is as follows:
Up to the end of this summer, the mower was running just fine, although it did need to be serviced.
Note: I did hit a rock, which bent the blade. I checked the shaft and it does not seem to be bent. White I was finishing that mowing session it was burning a small amount of smoke, it had not done that before. I was able to stop it and restart it to empty the bag a couple times.
Fast forward to the next time I need it, it will now not start at all no matter how many times I pull the cord.
It seems to have compression, but will not start.
So, I did a complete service on it. Replaced air filter, changed oil, replaced spark plug (checked gap), gave complete cleaning, including taking off fuel line and carburetor and cleaning.
It tries to kick over if I spray carb clean in carb, but won’t fully turn over or stay on.
I’m out of Ideas.
Jeff - Reply
Its the greatest machine ever BUT it moves too fast and I have problem keeping up, there must be a slower speed Please advise me THANKS
Umberto Schoeps - Reply
όταν λειτουργεί βγαίνει λευκός καπνός
ΓΙΑΝΝΗΣ ΒΑΣΙΛΕΙΑΔΗΣ - Reply
Long story short went to fold out handle on my Briggs & Stratton push mower and it seems like the pull cord doesn't go out far enough it's really tight when I get the handle into position to secure it I checked to see if it was getting caught on something and it does not look like it... what else could I do to extend the cord back to it's normal spot where I would be able to pull it back? It seems stuck or seized
I would truly appreciate any helpful tips thank you
lilred2090 - Reply
The pull cord won't release. Took the cover off,the pull releases. Turned it over to put back and again the pull cord doesn't release?
Denine Furney - Reply
Our 675is is built into a Cobra self-propelled mower. The engine has to be stopped to empty the grass box. Then it is hard to re-start. The standard start procedure does NOTHING. No buzzes, hums, clicks, just NOTHING. The battery is charged, the fuel is fresh, there is oil. However, to start the engine it is necessary to disconnnect and reconnect the battery. Then the engine starts first time, every time. Any ideas anyone?? Thanks in advance.
Tim Parker - Reply
How do I clean the fuel filter on my 675 engine?
Timothy Kruger - Reply
My Briggs and Stratton 675 binds up or kicks back when pull starting it .Both woodruff keys are intact. When turning the engine over it reaches a position that you can feel resistance.
tripperman34 - Reply