Checked my valves today - all good as far as clearances go. But when I put it back together the front tappet cover is leaking badly. I took it back off, made sure both surfaces and the o ring were clean, flipped the o ring over, and it's still dripping. This is a long weekend so I won't be able to get a new o ring until Tuesday. I'm wondering if I could use RTV or something like it to get by until I can fix it properly.