Mower will not idle up

[schwanksta]

I have a Murry 20" Classic mower with a 3.5 hp B&S motor that I rescued off of a trash pile a few years back. I showed it a little TLC (plug, filter, oil, etc.) and it worked well for me up until now. It starts perfectly and runs at idle, but it will not rev up at all. I pulled off the air filter and saw it was starting to crumble pieces into the carb, so I took the carb off and cleaned all of the little filters and parts I could find. I checked the gasket and cleaned out the gas tank as well. The problem persisted even after I put it back together. I pulled the plug, and it was pretty black (the plug is pretty new), so I cleaned it off. No dice. I cleaned the magnetic timing around the flywheel with sand paper. Same deal. I eventually pulled the new air filter back off and shot some starter fluid into the top of the carb. Instead of revving the engine up, it almost killed it. I think it's not getting enough air. Any ideas on how to fix that? I'm really not sure what to do next.

Any help is greatly appreciated.

Gene

 

[reddragon]

check to see if your governor is working....its the throttle linkage and spring to the carb....it should move by itself as soon as it starts

 

[schwanksta]

They seem to be working. If I open up the carb valve using the attachment point of the springs, the engine will run more roughtly and kill pretty quickly.

 

[reddragon]

weird...can you give us model/serial numbers of both mower and engine?...any pictures are a plus:smile:

 

[originalswampfox]

How much foam was missing from the air filter. I have actually had it through the cylinder and partially plug the muffler. Be sure all of that is cleaned out before spending money.

 

[reddragon]

it just hit me!...i had this happen to a string trimmer...the spark arrester was totally plugged....try cleaning your muffler...see if that helps.....or take it off to test

 

[Edwards saw service]

it just hit me!...i had this happen to a string trimmer...the spark arrester was totally plugged....try cleaning your muffler...see if that helps.....or take it off to test

The best way to clean it is to take off the spark arrester and muffler and get a propane or mapp gas torch burn off all the carbon off the arrestor then put the torch in the muffler (both holes) and all the stuff will burn off creating bluish gray smoke. When most of the smoke is gone most if the carbon build up is too. Obviously using long reach pliers to hold the muffler and arrestor. :-D