I have an old White Yard Boss GT1050, that is giving me fits.

I think i may have found the problem. I wondered if the intake runner might have a crack in it, so i removed it, and cleaned it. No cracks, but i also noticed that there was no gasket between the runner, and the governor bracket, and the bracket to the head. I cleaned everything good and reassembled with permatex #2, which is non hardening, and resists fuel, oil, and heat. Prime the engine, and it started as it did before. I was able to keep it running by playing with the choke. Much better than before. I then noticed that on the front of the head, there was a wet spot. I had cleaned the dirt and stuff out of the fines, but didn't use any cleaner. I cleaned it off, and dried it, and started the mower the see if it happened again. Sure enough it did. I knew then i had to pull the head. I found the gasket broken at the bolt hole where the leak was, and also a small leak at the rear. Not bad for a 46 year old machine. Gasket should arrive today. I am wondering, and will check, what the compression will be after the repair. Might be better than the 100 it had before. I will post the results after i get it together.

Update on the old beast. Got the head gasket, and compared it to the original. It was the same. Installed the gasket, put the new carburetor on, Still had to prime it. Still the same problem, with the exception of the carb leaking bad. Installed the old carb, leaks just as bad. I have worked on vehicles for 55 years, and to have a single cylinder old mower defeat me is not going over well. Briggs and stratton sent me an email, because i had ask about the gasket. I gave them the model, and code. The wrote back that it didn't exist. I sent them a nice pretty picture of the numbers, and the pic of the mower manual. I think the problem is that this engine was only made one year for this old beast. In 1975 they went with a 16hp, instead of the 10hp. I am going to let my brain settle for a few days, and think some more.

Yes, what i said is correct. The carb does look light the one you show.

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Thanks, i will take a look. Cannot picture where those would go.
 

You were talking on the emulsion tube that goes up through the carb. That is where they said to put the o-ring. My ubderstanding is that is brass on potmetal seat.

Actually it creates a seal around irregularities caused by corrosion. It was originally created to compensate for warping in fuel tanks on some small frame vertical shaft engines then some bright light discovered it worked here as well.