Getting the Scaley build-up off of the exhaust valves?
 

OK, I've been spending some time today cleaning up the heads which will ultimately be going into my my 2.2 race motor. Almost all of the exhaust valves have a scaley build-up on them that seems pretty impervious to a wire brush attachment on a drill. For comparison, the drill and brush seems to work great on the heads themselves. Some of the valves (from a different set of heads) have some really nasty black build-up. On one of them I tried using a gasket scraper to scrape the stuff off, but that is pretty slow going and dulls the scraper.

What's the best way to get the stuff off?

You can try soaking them in carb cleaner for a day or so.

Sherwood Lee
http://members.rennlist.org/911pcars

Bead blaster at the machine shop?

-Wayne

Leave them overnight, or for a day or so in a can of Berryman's Chem-Dip ... the build-up will come off very easily! A popsicle stick will be all you need to scrape them with ...

Thanks! SmileWavy

Soak them in a 2 liter pepsi overnight. Wonder what that stuff does to my stomach

Heheheh... it's frightening that it actually works!

Try soaking a hunk of beef in coke or pepsi for a day or so and see what happens to it.

BTW, if you use Pepsi for your valves, is this then recyclable as a refreshment (as long as it's cold and still has fizz)?

Sherwood

Bead blasting works, but CAUTION!!!! glass beads leave stuff behind. That stuff can do in an engine. If you bead blast, clean, brush, brush and brush again to remove any remnants of the beads.

NEVER bead blast a case. You cannot ever get all, ALL, the beads out. Beads are the top cause of engine failure on a rebuild. Thats per one of the top engine machinest magazines for engine rebuilders.