briggs old 12 series L head intake

[38racing]

I was sure i posted about this but couldn't find it. My friend's 128802 was hard starting and lacked power. I pulled carb and cleaned but in replacing noticed the intake pipe was loose. I tightened it and it ran fine again. Now I have it back just a month or 2 later (not used much either) and it will run only while pumping primer. I pulled carb and it's not a dirty jet so I pulled intake again. It's plastic. There was no gasket and plastic surface was no longer flat. I filed it flat but I have to order gaskets. I plan on using two. The intake shows as 497465 superceding to 794305 kit. I notice the new intake hole is not round but the gasket hole is still round. Old intake has round hole. I guess that there were metal intakes as well as I see note on kit picture about raising coil if going from metal to plastic. Anyone know why hole is non round on the replacement. Port in block is round.
https://www.repairclinic.com/PartDetail ... 05/1567993

[KE4AVB]

Appears to be a molding requirement so it can be released from the mold.

It will be round after you install the plastic insert that is in the kit. Just don't know how reliable these are since I rarely see a walk behind mower any more. Hopefully it is a good compression fit.

Not a fan of some plastic inserts especially the Kohler Courage single cylinder ones. They once had a one piece heat deflector but they wanted to reduce plastic usage apparently. Now the two piece design is wearing out the intake port on the cylinder head. I eventually require a head replacement. The cause of the wear is that the plastic insert gets loose from heat, then just keeps moving wearing itself, the main heat dam, and cylinder head.

[38racing]

Thanks. That explains that other piece in the kit picture. Funny though the original is round and plastic.