When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My 90 7.3 has a rough idle and is pretty sluggish. I'm going to advance/retard the timing and see if that helps any before I get a new pump for it. I was looking it over last night and noticed there are two sets of marks on it. I know the top set are factory.. What's the deal with the ones on the side? Are they factory or something else?
I too had a pump that had a mark in that area. Could just be someone marking it as a reference to go back to.
Looks like your pump has already been advanced a fair amount.
Interesting, I don't think I've seen side marks on my pumps.
Abywho, in the picture it looks like the factory marks are almost lined up, but the other marks aren't. So maybe with that pump it was a reference at one time?
However to make the reference marks line up you'd have to retard the timing beyond the factory set, which I believe is quite rare to make an IDI run its best.
