Briggs 18.5 hp Wont Run

kkjfjns2014

Member
Joined
Mar 20, 2023
Threads
2
Messages
34
Do these motors have a timing key? Could it have lost time?
Ok everyone so to recap, this is where I'm at.

I've tried 3 different carbs, two of them flood the cylinder and soaked the spark plug completely. The other one didn't seem to feed it any gas at all. One of the two flooded ones was a Nikki, the other two were generic Chinese replacement carbs.

The fuel shut off solenoid is a NON ISSUE. I've cut the plunger off one and have been swapping it around as I try carbs.

It has clean spark, good new gas, and I already adjusted the valves.

I'm about ready to throw a match on this thing. I don't know why the hell it just won't run. When I first try to start it it acts like it wants to start and will chug a few times before it floods with gas then it won't even try to start even after I dry out the spark plug and cylinder. If I leave it sit for a day it'll do the same thing the next day.

I officially hate briggs and stratton motors. I've never had this many issues out of any other brand ever. I have a kohler and it doesn't give me half this much shit. I've had a few other briggs motors and they always seems to hit the shitter and become unfixable way to fast.
 

smhardesty

Well-Known Member
Joined
Dec 8, 2022
Threads
25
Messages
272
First, You problem isn't just because it's a Briggs engine. There are a lot of guys that would argue that they hate Kohler because they had a similar problem they never could get fixed on a Kohler, but they never, ever had a problem with a Briggs. So, rule that complaint null and void.

Secondly, maybe you just need to do a true and proper diagnosis of the problem, following a logical troubleshooting sequence. I have attached a very extensive troubleshooting flow chart. Maybe you should go back and start troubleshooting step by step.

https://images34.fotki.net/v1681/fileAjMx/a7ac4/2/3733132/14239300/Diagnosticflownostart.pdf
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
65
Messages
24,995
I cut the fuel solenoid plunger off to remedy any issues it would have. Tried to start it today and it's blowing gas out of the exhaust with the nikki carb back on it. So it's obviously flooding right? How do I remedy that?
Depending upon which Nikki carb you have you need to clean the carb and if needed replace the float needle
If it has the white plastic jet holder with the complex O ring style gasket they are prone to leaking around the inlet O ring
Note there are 2 styles of this carb & thus 2 gaskets
Full details in pictures on out door power info web page
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
65
Messages
24,995
Mower engines are made to a price not to a quality level
And as Kohlers are more expensive it should be no surprise they give fewer problems apparently .
However you have to view this in contex that B & S probably outnumber Kohlers 300 :1
I hate B & S engines because they are designed by accountants so every fastener is the smallest one that will do the job in what form that is cheapest to buy
So to pull one down you often need better than 10 different tools
Most kohlers need only a 10mm socket & either a torx or std screwdriver
On top of that people who buy the cheapest by & large do not respect their gear and abuse it without any thoughts of maintenance till it goes bang & stops
Then they ring me and ask "how much it cost to service their mower "
And of course no one ever reads their owners manual till their mower stops running.

As mentioned above very few do a proper diagnosis and in may cases they fix the symptoms & not the problem.
 

Brucecooke212

Forum Newbie
Joined
Jun 26, 2018
Threads
1
Messages
2
Hello all, I have a 2006 briggs and stratton 18.5 HP [31N707] engine that came off a craftsman. We put it on a small ariens zero turn. It worked very well for awhile, then got it where it wouldn't run unless the choke was on. Eventually it quit running all together. After this my dad parked it and it sat for 2 years.

I decided to try and fix it for him this year. There was water in the gas, so I took that tank off and drained it and dried it in the sun for a few days. I put it back on put in fresh gas. I also replaced the carb and all fuel lines and vacuum lines and filters. I put the choke on and started it and it ran for about 10 seconds, I took the choke off and now it's back to not running at all again. Tried tinkering with the air/fuel mix a bit, still no luck. If you feed it gas directly into the carb it will run. It has good spark, everything else seems to be functioning, I have no idea what else to do. I'm about to pull my hair put. Any advice on next steps would be greatly appreciated. Thank you.
Make sure the return choke spring is on and works properly 💁‍♂️
 

jenneir

Forum Newbie
Joined
Mar 26, 2023
Threads
0
Messages
1
And then this is done and the engine come into my shop it gets a new solenoid and customer gets the bill for being stupid. Sorry but is how I feel about it but it is one stupid thing that can fixed. Other stupid things can't be fixed.

Oh btw those fuel solenoids are cleanable.
 

biggertv

Member
Joined
Mar 31, 2017
Threads
0
Messages
47
Could be a bad Coil even if you have Spark. Usually it dies when Hot is first symptom. Spark will be Yellow instead of Blue. If you have Fuel and Compression...
 

kkjfjns2014

Member
Joined
Mar 20, 2023
Threads
2
Messages
34
Could be a bad Coil even if you have Spark. Usually it dies when Hot is first symptom. Spark will be Yellow instead of Blue. If you have Fuel and Compression...
Wow, I noticed a yellow spark when I was testing the plug and didn't even know that was a thing. That is awesome. I'll be ordering a new coil today
 

biggertv

Member
Joined
Mar 31, 2017
Threads
0
Messages
47
Don't pay too much! I get most of my parts from Amazon. Look for free returns. Most are made in china anyway... Check Reviews and sort by confirmed purchase. Your first clue was Wet Spark Plugs. Good Luck!
 
Top