Irritated

[bluegill44]

I have a Troybilt self propelled 6.75. I rebuilt the carburetor and put fresh gas in.It started right up but it was running bad kinda like surging. by that I mean it would speed up then slow down. I put a new Carburetor on and it does the same thing. Does anyone have any ideas what could cause this?

 

[Scrubcadet10]

Could be your intake tube is cracked. That will allow air to enter the fuel system past the carb. Does this engine have a mechanical or Air vane governor?

 

[mechanic mark]

post complete model & serial numbers

 

[cpurvis]

Did you replace in intake gasket(s)? Surging is sometimes caused by a lean condition.

 

[mechanic mark]

https://www.briggsandstratton.com/na/en_us/support/faqs/browse/engine-problem-solving-tips.html