That trick with tapping a stuck valve cover actually works

I had a valve cover on a CAT engine that wouldn't budge after 20 minutes of prying near Galveston last month. Tried tapping the corners with a rubber mallet like an old timer on here said and it popped right off on the third hit. Has anyone else had luck with that on older diesel engines or am I just lucky?

3 comments

3 Comments

troyknight3d ago

Can't tell you how many times I've been the guy beating on something for way too long and feeling like a total fool. I spent a good hour trying to get a valve cover off an old Ford 6.9 once, using a pry bar and a lot of bad language, before I remembered that rubber mallet trick. Third tap and it just gave up. Felt like I won the lottery but also like I should have my toolbox taken away for being so dense. It's not luck with the engine, it's just that the rubber mallet vibrates the gasket loose without bending anything. I swear those old diesels just need a little convincing, not a fight.

wilson.olivia3d ago

Did you try hitting it from a few different angles too? I had a similar fight with my old Cummins and found that tapping around the whole perimeter works way better than just one spot.

emmaking3d ago

Right? I've definitely been there with a rusted bolt and a lot of bad choices.