Briggs 5hp with no blade

[Rivets]

If it’s like the one pictured in post #7, I’ll be glad to help you, but you’ll have to wait till tomorrow as I’ve had a long day. Just so we’re on the same page, shoot me the numbers off the engine and/or the carb part number. I’ll get back to you after I get done with the Sunday Honey Dew list.

 

[Hammermechanicman]

It is like the one in post 7 except it has the auto choke. I will get the engine numbers tomorrow. I have a couple riders to pickup for annual maint tomorrow so i will be out in the shop tomorrow afternoon working.

 

[PTmowerMech]

Hey Rivets, throw me a bone here. I have one of the briggs with the plastic carb (auto choke model) that i have put 2 new carbs. Came in for hard starting and surging. New carb, once it starts it runs fine with no surging but you have to use some starting fluid to get it to start. After it runs a few mins it will start right up. Sets till cold no start. Other new carb hard to start and slight surging.
Things i have done, check head gasket, valve sealing, valve lash set, new spark plug. Flywheel key, auto choke. if you have worked on 100 of them you got any ideas why the hard starting?
Thanks

Check to see if the choke is hanging up on the bracket that holds the carb on. You'll probably have to take the top cover off, to ge a good look at the top of the carb. With the choke off, as in when it's running, that choke lever could stick on that metal carb bracket. And when it cools down, it won't return to choked position.

With the engine and the cover off, just move the choke open and closed to see if it's hitting where I'm talking about.

 

[PTmowerMech]

My experience with these carbs ( I’ve done at least 100) is that even a slight over size can cause smooth running problems. I use a .0145” micro drill (#78). I’ve tried .016” (#77), but don’t get the results I like. Over sizing will make it easier to start, but I’ve found I get rich mixture surging.

I drilled the 2nd one today and if it's running rich, I can't tell it, or smell it. Gonna run them a little more tomorrow and check the plug. My calipers don't give me enough digits to say what size the bit I used is.
But no surging at all.

 

[Hammermechanicman]

Check to see if the choke is hanging up on the bracket that holds the carb on. You'll probably have to take the top cover off, to ge a good look at the top of the carb. With the choke off, as in when it's running, that choke lever could stick on that metal carb bracket. And when it cools down, it won't return to choked position.

With the engine and the cover off, just move the choke open and closed to see if it's hitting where I'm talking about.

The auto choke is working as it should. Thanks for the tip.

 

[Rivets]

When you get the numbers I’ll get back to you.