This motor is on John Deere GT235 lawnmower motor# 350777-1137-E1.

I just bought it and this vacuum line wasn't hooked up, it's on front left side of carb (looking at it). Does anyone know where it goes ? Could you please tell me so I can hook it up properly. There is a second hole in the air filter backing plate just below the main PVC hole but its a little big for the vacuum line. I will include pictures. Thank you in advance.

https://postimg.cc/MXd087Gr

I responded to your PM in regards to that vent line...
 
 
 

Also, new folks on the forum are often denied immediate ability to post pic's W/O 
admin approval...
 
 
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Thank goodness the picture appeared. Does this vent go in the backside of the air filter housing?? There is a hole there

It's very possible as it's venting, you'd want it in a "protected / filtered"  area away from flying grass/dirt.
 
Is the line about the same length to fit in that hole W/O mods? 
 
Is the hole about the same size of the hose? (thought it was different).
 
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