the_kai•14d agoProlific Poster

Debate: Should we flush cooling systems on a strict schedule or only when there's a problem?

I had a Cat C15 last month that ran fine for years with no flush until the water pump seized at mile 350,000. Another shop swears by their 500-hour flush plan and never sees failures. What's your rule on this - stick to the book or wait for symptoms?

2 comments

2 Comments

riley_bell14d ago

Is it really that big of a deal though? I mean, 350,000 miles without a flush on that C15 sounds like it did fine for a long time before it finally gave out. Seems like a lot of shops just push the schedule to sell more service work when the real issue is usually bad coolant or a part that just wore out.

loganm5214d ago

Heard a guy from a fleet testing lab talk about this once and he said the real killer isn't just the old coolant, it's the little bits of liner seal that break off over time and clog up the oil cooler. Once that happens you lose oil pressure to the top end and it's game over. So yeah maybe the coolant chemistry wasn't totally shot yet, but those rubber seals and gaskets degrade even if the fluid tests fine. Kinda makes the whole "it lasted 350k" argument less impressive when you realize the engine was slowly eating itself from the inside the whole time.