Briggs mower won't start

[KE4AVB]

You got kidding about the pressure. It isn't like I can completely go blank in front of customer at times especially on something I haven't seen a while. Just too many irons in the fire.

Now what we were we discussing?........Oh the plastic carburetor. Boy do I need look at one the next time one these comes in. The last couple I repaired but didn't pay that much attention to the actual setup. Running on auto pilot.

[Luffydog]

Ke4avb check your pm

[38racing]

i actually removed drain plug when I had carb off. thought I broke it due to twist lock instead of threads.

[KE4AVB]

Hmmm Already changed them I reconken. The ones I have seen were threaded. Tnx for the note.

[Luffydog]

I know all about the auto pilot keep all that rain down your way

[Luffydog]

funny this thread came about when it did.... 3 of the these carb came in today all push mowers with same engine and same issues

[38racing]

Well it runs but of course I don't know why,lol.
No room to remove drain plug until I loosened carb most of the way. Had gas in bowl. So I took it apart again.
I did remove float and needle.
This time I checked for housing passages. I found what I assume are 2 air bleeds. Looking at choke end one is at 2 o'clock. It feeds into jet assembly housing at location of the non o-ring stack. Carb cleaner went right through.
The other bleed was at 9 o'clock and based on looking at outside of carb it fed to the base of the o'ring stack. Picture here.
http://web.ncf.ca/da229/smallengine/bob-carb-1.jpg
I could not get any flow of carb cleaner from either end after repeated tries and also with compressed air. A wire from choke end went well past the down piece. A wire from the inside of carb seem to go up to the horizontal but I could not see it by looking in the choke end.
There is a welch plug but I have no idea what passages it covers.
With the jet assembly I removed the centre piece this time. Again I sprayed all jets and tube holes with carb cleaner. I was able to insert a .55 mm pin into the side jet but .60 would not go.
Although shadow of ball bearing seem to show it clear of the jet opening I still used a drill bit to press it down just a bit.
so I put it back together and it started and ran fine. I shut it off and it restarted.
But I still have 2 things. I should have removed the gasket at choke end . it expanded from carb cleaner. I assembled without it for the test run. Maybe it will shrink back when dried out. I think that's happened when I've done it to a bowl gasket.
Next thing is more puzzling. When I pulled the carb off the spacer, the white plastic ring and black rubber o-ring stayed on the spacer. When I re-installed it the o-ring went inside the carb neck but the white plastic is pressed between carb and spacer. I'm guessing that it's wrong because the videos I've viewed show the white ring in the carb. Mine looked like this so I guess I'm pulling it once more.
http://web.ncf.ca/da229/smallengine/bob-carb-1.jpg
As an aside I pulled the shroud to better access things. Took a bit to figure it out. Two recessed screws at the back but it would wiggle but not come off the front. Turns out there is a hooked tab that has to be pushed with a screw driver. there's a hole in the front to put the screw driver, which I found was under the B&S decal.

[Luffydog]

Glad to hear you got it going. Takes time figure it out sometimes and sometimes you never will but it works as in your case so I am going to practice just what you posted it worked for you so I'll try it on others that showed up today all with no starts with this plastic carb that's cost $2.50 to make and costing them more to figure out. Thanks for your update.

[38racing]

I remounted it with the plastic white ring inside and the outer gasket did shrink back to size. it starts firts pull cold and on restarts after short run. thanks for all the guidance.

[bgsengine]

I remounted it with the plastic white ring inside and the outer gasket did shrink back to size. it starts firts pull cold and on restarts after short run. thanks for all the guidance.

if its what I think you mean thats wrong - you mean you don't recall the old briggs lawnmower engines with aluminum body pulsa-jet carbs mounted on the tank? if you did you may recall the (formerly square-cut) o-ring seal that sealed the carb mounting to the crossover intake tube. plastic body carbs like yours (as well as the plastic body pulsa-jets) have the same style of sealing - the "white plastic o-ring" is a replaceable service part that simply makes up the groove in the carburetor that the rubber o-ring seats in. So, in your linked photos above, those pieces goes in the end on the left side - the o-ring goes in that end first then the nylon retainer snaps in place into the carburetor body which retains the o-ring in place - That is your intake gasket - if the o-ring vibrates out , gets loose, cut, or hardens, it can leak air and give you some weird running problems.