3.5hp briggs question-----carb????

[mrfred54]

I have an old pushmower with a briggs engine, model 92902,type1982 01. I have replaced the diaphragm for the carb. and still have the same issue. it will only run if I hold the throttle wide open. it will not run even at half throttle. I have the throttle cable unhooked and am operating the throttle shaft with my finger. any ideas what to do next. thanks in advance

 

[Rivets]

It could be a couple of things, bad seal between the carb and tank. These tanks were know to warp. Not preloading the diaphragm when tightening the mounting screws. Sequence is in this manual. Hope this is of some help.

https://docs.google.com/open?id=0B6NaqjIxWV1ycG8wd0s3Z2Q2X00

 

[lugnut1]

air filter clean?
after checking all exterior of carb for leaks

adjusting if possible:
if it has carb air/fuel adjustment on it you may want to screw it in counting the number of turns until it just gets snug (don't over tighten) and then back it out the same number of turns then try turn it at 1/2 turn more out or 1/2 turn more in or usually somewhere in between.

cleaning:
you'd want check fuel tank for foreign matter (dirt, rust, etc.) clean if needed (I've found earwigs in tanks before)
clean the interior of the carb ( passages, pickup screens ,jets, etc.) with a spray carb cleaner. (I use gunk carb spray cleaner)
make sure all passages are cleared.
doesn't take much to plug up carbs ( dirt, varnish, etc.)

 

[lugnut1]

parts diagram (page D or E for carbs)
Briggs and Stratton 92900 Series Parts List and Diagram : eReplacementParts.com

 

[mrfred54]

found the problem. it was the intake tube gasket. it was missing about a 1/4 of the gasket,must have got sucked into the engine. thanks for all the responses.