briggs running very rich

[Gator]

Got a briggs 5hp it has the tank mounted carb, its a non adjustable pulsa-jet.
I just bought the engine, and it had been sitting for a long time.

I cleaned the carb, wich looked pretty good compared to the tank, also cleaned the jet orfices and everything. I also cleaned the tank and also removed the in tank foam bc it was breaking down.

Engine will start on 1 or 2 pulls

Will not idle, even with idle screw maxed out. I have to crack the butterfly on the carb to keep it running, and its bad rich. If you blip the throttle it boggs, if you hold it wot it revs but is rich and is being held back bc of being rich.

Can a bad diafram cause a very rich condition?
what else?

heres the exact carb i have. mine has the fix jet in the bottom, like in pic 4
http://outdoorpowerinfo.com/repairs/briggs_pulsa-jet_horiz_fixed.asp

 

[Jmiller_usmc@yahoo.com]

u might need a new rubber fuel pump that should fix it u can get a carb rebuid kit for like 20.00$

 

[Gator]

u might need a new rubber fuel pump that should fix it u can get a carb rebuid kit for like 20.00$

can a diafram/pump ever cause a rich condition?

 

[Gator]

how do you remove the welch plug on the side of the carb, thats by the idle mix screw?
like in the first pic

the second pic shows whats behind the welch plug, im thinking the orfices are clogged in here, in the green boxes.

 

[Russ2251]

can a diafram/pump ever cause a rich condition?

Absolutely.

how do you remove the welch plug...

Use a very small cold chisel and CAREFULLY punch a hole and pry up. Not likely that this is the problem and removal should be avoided if possible.
Anyway...if these holes were jammed up it is likely engine would be running lean.

 

[Gator]

Absolutely.
Use a very small cold chisel and CAREFULLY punch a hole and pry up. Not likely that this is the problem and removal should be avoided if possible.
Anyway...if these holes were jammed up it is likely engine would be running lean.

Ok, thanks. I will try a new diafram first.

what else could cause a very rich condition?

 

[Russ2251]

Other than diaphragm, nothing else comes to mind.
Is good practice to replace diaphragm anyway if condition is unknown.
Just to be clear, screw you are referring to is idle speed adjust and not idle (low speed) mix.