wesley_jones•22d agoProlific Poster

Old Cat 3126 in a school bus threw a rod on I-40 outside Nashville last Tuesday

I was running a route for a local school district, just cruising along at 55 mph. No warning lights, no strange noises beforehand. Then a big bang and oil everywhere. Got it towed to a shop nearby and the mechanic said the number 4 rod went through the block. Turns out the previous owner had been running cheap oil and skipping changes. Cost me $3,200 for a used engine swap. Has anyone else run into hidden damage from poor maintenance on those 3126s?

3 comments

3 Comments

the_lee22d ago

My shop flushed the cooler twice before installing the replacement.

linda_dixon4922d agoMost Upvoted

$3200 is actually fair for a used 3126 swap, I've seen shops charge $4500 plus. The key thing on those engines is that cheap oil leaves a varnish inside that clogs the oil passages to the rod bearings over time. I'd also check the oil cooler and turbo for debris before you put the new engine in, leftover metal can take out the replacement.

the_claire22d ago

So @linda_dixon49, did the mechanic actually check the old oil filter for metal before you went ahead with the swap? Because I've heard of guys pulling a filter that looked clean on the outside but was basically full of glitter inside from bearings that were already starting to fail... if that was the case, you might have caught it before the rod let go. Also, did they flush the oil cooler lines properly or just blow them out with air? That's another spot where debris hides and then finds its way into the new motor. I'm asking because a buddy's bus got a replacement 3126 and it died six months later from leftover metal in the cooler.