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Murray 3.5 hp push mower....Help

Gail1956's Avatar

Join Date: Jan 2009
Posts: 1

01-28-09, 02:13 PM   #1  
Murray 3.5 hp push mower....Help

Let me just say, I know i'm stupid for buying this poc, but what's done is done . Actually, I bought this from someone to help them out for $. The mower ran and started fine the first couple times I used it. It is practically brand new and has requiured oil, gas etc. I wanted to start it today and primed it the required 3 times. It will start and run until the gas that is primed into the carb is burned, and then goes dead. It will do this every time. Any suggestions as what i could look for? I have changed the plug. That is about the extent of my mechanical ability, but i would try working on it just for fun. Thanks in advance,Gail1956.

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cheese's Avatar
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Join Date: Jul 2001
Posts: 16,570

01-28-09, 04:03 PM   #2  
The carburetor diaphragm probably needs to be replaced. It commonly gets distorted under the plastic carb between the screws on either side of the connection to the intake. Clean the carb while you have it off the tank. It's an easy job that should take less then $5 to fix.

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God bless!

geogrubb's Avatar

Join Date: Jun 2006
Posts: 2,333

01-28-09, 06:46 PM   #3  
You need to install a new diaphram kit, it is Briggs part # 795083 or old # 495770 also Lowe's has a kit #5083 which has the same parts.

Here we go;
Remove air cleaner, there are 2 bolts that hold things together, one on the front of the tank 3/8" and one into the block 1/2", remove these bolts, now "slowly" slide the carb/tank off the intake tube and breather tube, now tilt the tank in to release the throttle linkage and waalaa the carb/tank is removed. Remove the 5 screws from the carb/tank remove carb(don't loose the spring) now spray all holes, cracks and crevases in both the carb and tank surface with brake parts cleaner, remove the main screen(looks like a thimble) with a small screwdriver pry out the main jet(carefully) and clean it, reinstall the jet, it can be difficult some times to get it to snap back in place(I use the rounded end of a screwdriver handle). Remove and clean the fuel pickup stem. Clean any junk/rust from the tank. Install the diaphram on the tank then the gasket(no goo or sealer) now carefully replace the carb(the spring will try to misalign the diaphram), tighten all screws a little at a time so as not to crimp the diaphram until they are all tight. Install the carb/tank in reverse order and you are done. If I missed something one of the real mechanics will correct me. Have a good one. Geo

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