Spent three full shifts on a single fuel pump issue

I was working on a Cummins ISX engine where the fuel pump was acting up. It took me three entire shifts to trace the problem to a tiny seal that had worn out. Every time I thought I had it, something else would leak or not seal right. How do you guys handle jobs that just keep going like this?

3 comments

3 Comments

the_hugo6d ago

You mentioned that tiny seal wearing out, but in my experience, it's often a sign of something else going on with the fuel system. Those Cummins pumps can have issues with the alignment of the gears, which wears out seals prematurely. I got sidetracked once replacing seals over and over until I realized the pump body was scored from debris. Now I always inspect the whole assembly first, even if it means pulling more parts.

spencer_bell6d ago

Those Cummins gears misalign, shredding seals in hours.

alexj992h agoMost Upvoted

Man, that sounds brutal. So when you found the scored pump body, did the gears look okay or were they chewed up too? Just trying to picture the whole failure.