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View Full Version : 18 Horse Briggs missing badly


Dirty Water
07-16-2006, 09:44 PM
Like the subject says, my sister in laws craftsman mower is missfiring badly.

Common problem? Easy fix?

Restrorob
07-16-2006, 10:05 PM
Is it a single or twin ? Model numbers tell all Jon.

Dirty Water
07-16-2006, 10:10 PM
Is it a single or twin ? Model numbers tell all Jon.

Single, sorry...its not my mower, and I'm not around it.

Restrorob
07-16-2006, 10:36 PM
Well, If you had a in-line spark tester that would tell you if it was ignition or a mechanical problem. It could be ignition, carburetor, valves or even the flywheel key. Will it smooth out if the choke is applied slowly ? That would mean carb. problems.
You can go to post 3 in this thread for proper valve adjustment if you want to check that; http://www.lawnsite.com/showthread.php?t=147559

Do some checking and see what you can find.

Dirty Water
07-16-2006, 11:18 PM
Well, If you had a in-line spark tester that would tell you if it was ignition or a mechanical problem. It could be ignition, carburetor, valves or even the flywheel key. Will it smooth out if the choke is applied slowly ? That would mean carb. problems.
You can go to post 3 in this thread for proper valve adjustment if you want to check that; http://www.lawnsite.com/showthread.php?t=147559

Do some checking and see what you can find.

It does smooth down with the choke partially applied. My thought on that was carb problem's too.

I don't know much about small engine carbs though, I grew up wrenching on '80s EFI cars.

Restrorob
07-16-2006, 11:50 PM
There is nothing to these little carbs., Here is the break-down for both. Either one could be on that engine.

See Ya

Restrorob
07-17-2006, 12:07 AM
The first pic. was blurred from my accelerator, Here's another try.....

Dirty Water
07-17-2006, 12:13 AM
What do you think the issue is if its smoothing out when the choke is applied?

As in, what should I look for if I dismantle the carb?

Restrorob
07-17-2006, 12:27 AM
Trash in the main jet (where the bowl nut screws in on the Walbro) the same area on the Nikki. But you want to shoot carb.& choke cleaner thru ALL holes and passages followed by compressed air while you have it apart. Check fuel tank for trash and clean if needed then replace the fuel filter and flush fuel lines for a proper job.