Troybuilt pony 17.5 hp Model#13wn77k5011

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Try spraying some WD 40 where the intake hits the block.. Top and bottom to check for a air leak also where the carb bolts tooooooooo.......
 

bertsmobile1

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tbonpc,
Surging on a governed engine is nearly always due to a low fuel air ratio.
Either because it is not getting enough fuel or air is leaking after the carb.
Occasionally , well quite rarely it can be electrical.

SO to get rid of the electrical bit, start the engine and hold the governor with your fingers.
Start with it running slow then slowly move it up to full speed.
If it runs fine slowly then starts to spit back through the carb you have a fuel problem.
If it backfires through the muffler then you have an electrical problem.

Having decided it is fuel then we start with the easy bits first
1) replace the solenoid in the carb with a bolt
runs fine = solenoid problem
2) pinch the fuel tank from your push mower ( or anything else that is handy ) and hang it from the rafters so it is a good 1' - 2' higher than the carb & connect it to the carb
runs fine = obstruction in the fuel supply.
3) do as Bou described , spraying the WD40 all over the inlet manifold , only hold the governor rod so the engine is running about 1/2 to 1/3 full speed.
As he mentioned, if the engine faulters & blows white smoke then you have an air leak.

Now just because ou bought a new carb, do not assume it is a GOOD carb unless you bought it from a real mower shop or real mower parts supplier.
And by real I mean one that has a street address when you can pick up from.

The only scrap in China is what they import to make new parts from.
Everything that rolls off an assembly line gets sold.
So the carbs that Briggs reject as being substandard / faulty will get sold on line as an OEM carb, what they fail to tell you is it is one that might not work.
If you get the entire kit, put a steel rule across the ends and make sure the rubber seals sit slightly higher than the end, if not, it can not make an air tight seal.There was a batch that ended up down here where the red rubber rings were all too thin
 

tbonpc

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Re: Troybuilt pony 17.5 hp Model#13wn77kG011

Is there any other carburetor that will work on this mower. B&S Engine Model # 31C707 0603 B2
 
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Re: Troybuilt pony 17.5 hp Model#13wn77kG011

Is there any other carburetor that will work on this mower. B&S Engine Model # 31C707 0603 B2

I think I have a replacement carb for your engine in my used parts section..... It is a Nikki Carb and I do know it was a running carb when the engine threw a rod.......

I will let you know in a day or or so..........

Let me know Mon Ami ~!~!
 

tbonpc

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Re: Troybuilt pony 17.5 hp Model#13wn77kG011

I think I have a replacement carb for your engine in my used parts section..... It is a Nikki Carb and I do know it was a running carb when the engine threw a rod.......

I will let you know in a day or or so..........

Let me know Mon Ami ~!~!

Thanks, at this point I am will to try anything to get it running again.
 

bertsmobile1

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Re: Troybuilt pony 17.5 hp Model#13wn77kG011

Thanks, at this point I am will to try anything to get it running again.

Well you could go back to post # 13 and do three tests outlined there and post your results.
 
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Re: Troybuilt pony 17.5 hp Model#13wn77kG011

Well you could go back to post # 13 and do three tests outlined there and post your results.

Yes Tbon go thru all the things Bert said to do..... Some carbs from Ebay are good as said and some are not.... A brand new carb from ebay at 15 to 20 bux is a maybe a NO NO. Some will will be OK........ You can cross the state line into Mississippi and gamble that also....

Yes I lived in Alabama and Miss. cause my job brought me there many moons ago. Katrina tore my house up on Bayou Cumbest in south Alabama....But I came back home after 7 years away from my home in Louisiana.....

I would advise you to go ahead and remove the welch plug and clean well like said before.......... Briggs number 690727 for 3 bux is cheap and a good cleaning on the carb also..... That is the main reason for surging right there.......I have done it toooooo many times on those carbs..... They are very finicky and I have advised a few people on this forum of that and they are up and running right now......

Again like Bert said take a tank off of another push mower with fresh gas and keep it above the engine to run yours.....

Please do some diagnostic tests like we say to try and solve this.... We are on this forum to help people, and we have a great track record....... We don't charge for advice, as the old adage says,,,,,,, Good advice is free....

Let us know Mon Ami ~!~!
 

tbonpc

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tbonpc,
Surging on a governed engine is nearly always due to a low fuel air ratio.
Either because it is not getting enough fuel or air is leaking after the carb.
Occasionally , well quite rarely it can be electrical.

SO to get rid of the electrical bit, start the engine and hold the governor with your fingers.
Start with it running slow then slowly move it up to full speed.
If it runs fine slowly then starts to spit back through the carb you have a fuel problem.
If it backfires through the muffler then you have an electrical problem.

Having decided it is fuel then we start with the easy bits first
1) replace the solenoid in the carb with a bolt
runs fine = solenoid problem
2) pinch the fuel tank from your push mower ( or anything else that is handy ) and hang it from the rafters so it is a good 1' - 2' higher than the carb & connect it to the carb
runs fine = obstruction in the fuel supply.
3) do as Bou described , spraying the WD40 all over the inlet manifold , only hold the governor rod so the engine is running about 1/2 to 1/3 full speed.
As he mentioned, if the engine faulters & blows white smoke then you have an air leak.

Now just because ou bought a new carb, do not assume it is a GOOD carb unless you bought it from a real mower shop or real mower parts supplier.
And by real I mean one that has a street address when you can pick up from.

The only scrap in China is what they import to make new parts from.
Everything that rolls off an assembly line gets sold.
So the carbs that Briggs reject as being substandard / faulty will get sold on line as an OEM carb, what they fail to tell you is it is one that might not work.
If you get the entire kit, put a steel rule across the ends and make sure the rubber seals sit slightly higher than the end, if not, it can not make an air tight seal.There was a batch that ended up down here where the red rubber rings were all too thin

I have done all this, hanging a tank higher above the steering wheel, sprayed WD40 all over intake, plugged the antibackfire hole with a bolt, tested all 5 of the safety switches (all Good), adjusted the valves .004 in .006 ext, put 1 oz of sea foam in a gallon of fresh gas, changed to oil, changed the air filter, puled the welch plug(allclean) sprayed ever port and openning I can see on the carb. Ran a thin wire through everthing, . Starting to think it maybe be a worn governor gear. Anyway thanks for the tips and advise.
 
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Tbon I saw your video and that's not a sign of a governor...... That's the sign of a dirty carb or a air leak some where....
 
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