12 HP B&S won't run but starts

thehill

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The mower had been running all season. But the last time I tried to use it it started right up ran 10 seconds and died. It would not restart

I took off the kill wire and tested it with a spark tester. I have a spark. Put back together poured a little gas in carb and after a few pulls it started and ran fast for a couple of seconds and died. So it seems to be a fuel problem. Took it to the local shop and they blamed it on the throttle assembly. Where the throttle cable attaches, the assembly broke off but I rigged it to hold it at a high speed and the governor works normally. I put the choke on and off manually. Shop blames it on the throttle assemble which is no longer made and promptly offered me $50 for the mower for parts. This seems to be a fuel issue, not a governor issue since nothing has changed with it. Any suggestions on how to proceed?
 
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bertsmobile1

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Lets start at the beginning with the model , code & serial numbers so we know which one of the 87 different 12 Hp engines you have
And yes it does sound like you have a fuel problem
But I do not feel like typing 120 pages to cover all of the possible repairs .
If you can start it and keep it running for around a minute by continually shooting SHORT shots of carb cleaner or starting fluid down the carb throat that confirms a fuel problem
It will knock a little when you do this and too much will flood the engine so just a little at a time .
 

Bertrrr

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Pull and clean the carb and all components of the fuel system , hoses , filters , tank etc. then retry
 

thehill

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Thank you for responding.
Here are the specs on the mower:
1. Engine Model 283707 type 0136-01 code 9612267A
2, carb Walbro WMT 4993 other numbers on carb are 63 1721 498888

I do use a shutoff valve and run the gas out when I put it up.

I chacked my records and beginning of last year I did clean the carb, put in a new float, new gaskets, new fuel line. valve , and filter. I have verified that gas flows out the line attached to the carb. I think because if that I thought it was probally electrical. But I tested the spark without wire on terminal, replaced the wire going from the binding post at the throttle govonor to the magento terminal, left that wire off and tested spark and then tested cranking and no fireing. It wasn't until I poured somer gas into the carb that it hade a fired and ran fast for two seconds and stoped.
 
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