Poor Coca Cola on the rust it will eat the rust away. ( and we drank this stuff)

Looks like you have a new boat anchor ( the heads ). Appears to be a lost cause, in my opinion.

I didn`t see head bolts in the photos --- are they rusted away too ?

Agreed, time for some new heads or pull and try to salvage. It would make a huge mess but you could always try a small hand held sand blaster and try to clean the whole head up and shoot some new paint on for the rest of the season at least.

muranic acid will eat the rust off!!!

Yup that is what I would do. Then get some anti acid to spray on things when you are done. That is one hell of a mess you go there!

The single most accurate statement in this whole thread.

NO CHITHOW IN THE HELL DID YOU LET IT GET THAT WAY...

If it runs for the time being leave it alone. If not, then as has been said, throw it in the trash and buy a new motor.

I think they meant muriatic acid which might work, there is a product called naval jelly which might work also.

My preference would be sand or bead blasting

If you use acid, have plenty of water handy to flush it off

That looks like a snowplow truck from up here in the northeast... I've seen a ton of them. You aren't spraying anything on there that's gonna help. Best bet is to break the pocelain, and pull it out (it's tapered, so it'll pull out of the steel body). Then, you can use a SQUARE style e-z out, not the spiral style, tap it into the opening where the porcelain was. Snap-on tools square e-z outs work excellent. Use some heat sparingly on the head around the plug... don't use too much, cast iron isn't real forgiving if you get it red. This works 4 out of 5 times, I've done alot of them. Otherwise, you're pulling the heads.

Good luck.