VP AQ225E engine block water drain-gctid812281

[Guest]

Hello everyone,

We've owned our `86 VP AQ225E (305 V8) since 2006. I noticed the first year that I drained the block for the winter, that the starboard drain plug wouldn't screw in very far. The bolt had a 15mm metric head, to boot. So, yesterday I'm buttoning everything up, getting ready to fire up for the first time, and I can't get the bolt to screw into the drain. It started to, and then basically fell out. The threads on the bolt (brass) don't look too good. Does anyone know what size bolt is SUPPOSED to be used for the block drain on a small-block Chevy?

Thanks for your help!

Rick G.

[kevinv123]

SAE standard 1/4-18 NPT. If possible blow the hole out with compressed air and run a tap into it to clean the threads. Don't actually cut any metal, just run it in until you get some resistance and back it out. Use a little motor oil or wd-40 type lube on it.