how to remove oil filler cap



hello group = just bought a 91 trans sport and love the drive and ride - but im tryig to check fluid levels and cant get the oil filler cap off...ive twisted and turned and even tried prying it off with a claw hammer - what is the secret to getting the cap off..the owners manual says NOTHING ! very frustrating! pre thanks for any help and advice!


New member
The cap on my '90 Trans Sport was just as stubborn

I finally got it off by digging my fingers under it on opposing sides then rocking it back and forth until it finally popped free. The valve covers don't have any sort of provision for a classic twist-on cap, so you're stuck with what you have. I lubed up the sides of the push-on cap with oil before reinserting it. We'll see if that helps in come out any easier at the next oil change.

Unlike later engines, the valve covers on these motors are made of metal; so don't feel like you need to hold back when trying to pry off the oil cap.


New member
It sounds like the rubber cap has reacted to oil and heat and over time it has become bigger. I have a 3.1 that I know this has happened to.