I bought my 1989 300 SEL off the internet sight unseen. Ya I know; I’m an idiot. Believe me; I’ll never do that again. Looks great, low mileage (91K when purchased 1.5 years ago), and one owner, but lots wrong with it. I’m now at 125K, hopelessly upside-down in the thing and it’s starting to make a clacking sound like a cam or lifter is going. I do like the car. It’s a great looking car, black on tan, but it is getting some rust. Interior is mint.
With all that said, I’m contemplating yet another large investment into a new cam at the least and possibly a top end rebuild. I live in Northern Wisconsin and the weather is rough on the cars up here. The body continues to degrade in spite of the beautiful interior and potential good mechanicals. I did a compression test with the following results in numerical order starting with #1; 165, 167, 155, 155, 175, 165. Can anyone help me interpret these numbers? What should compression be, and what kind of variance is acceptable? I know there are a lot of factors that influence compression. How hard is it to change the cam? I guess my point is if the rings are also bad, it may just be time to cut my losses and move on.
Thanks for any ideas.