Be careful with mission-critical parts

OK, here is my tale of woe, hopeully someone else will learn from my trials. Last summer, the engine of my SC Riv 3.8 with 140k miles started making a terrible noise from the general area of the timing gear. So off came the belt tensioning assembly, water pump, and harmonic balancer. Whoa! One DISINTEGRATED harmonic balancer! The rubber that held the two pieces together had shredded and there was about 30 degrees of play between the timing tabs and the hub. I replaced it with a DORMAN (made-in-China) balancer for about $100. Replaced the timing chain, gear, and water pump, as long as I was there. Not a difficult job, just a bit annoying because of the stuff you have to move to get to the bare front cover. Car ran great, for exactly 405 miles. Limped home one night around Thanksgiving and as I creeped up the driveway, it started spewing oil out the front seal all over the place. Three months of miserable cold weather and the Riv had to sit on the driveway until three weeks ago when I put together enough will to see what happened. The answer was pretty quick in coming. When I took off the balancer (remember, made in China for $100) it came out in two chunks. Seems that the hub had fractured at the keyway and this was the cause, I figured, for the "running like crap". The splintered hub must've taken the front seal with it, causing the oil hemorrage. Off came the front cover (in order to replace the front seal) and just for the hell of it I took a real good look at the oil pump, which on the 3800 is driven by the crank, just behind where the balancer sits. Good thing I did. The housing was cracked from the balancer failure and this is where I was losing oil. I took the balancer back to Lee Auto in Arlington Heights IL and told them my tale. They took the old balancer and gave me a new one, with no questions. Just for the hell of it, I took the new balancer to my machine shop of choice and this is the purpose for my rant.

The NEW BALANCER WAS DEFECTIVE!!!!!!!!!

Seems my machine shop guy Joe teaches at a local jr college and mentioned that the Dorman guy told him these things are failing left and right. So we checked the new one very closely. Not only was the keyway cut too wide, it was cut too shallow on one end; torquing this one on the crankshaft was sure to fracture the hub. Most likely this is what happened to my first replacement balancer - it started to fail as soon as I installed it.

One might be quick to label all stuff from China as crap and I'm not sure I would argue that. Certainly I will never go the cheap route on a mission-critical part again.

Perhaps the better lesson is to very carefully inspect (maybe a better word would be MEASURE) mission-critical parts.

Reply to
ralfwho
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What you describe is a typical of made-in-china. Get a new or used OEM one before made-in-china.

Reply to
Brent P

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