Cat 345bl blowing oil out dipstick tube when angled

Hi, my 1998 cat 345bl is blowing oil out the dipstick tube when I am angled back. It doesn't do it when tipped forward any kind of advice to get it to stop happening would be appreciated. It started on fire twice today with oil blowing on the exhaust manifold. I'm kinda scared to run it now as where I'm digging requires going up and down slopes. Thanks in advance for the advice.

Cat 345bl blowing oil out dipstick tube when angled