Blown Head was repaired, drove 2 miles, threw a rod

RLANDERS

MEMBER
GMC C1500

Good morning,

My name is Rob and I have a 1998 GMC Sierra 1500 4WD, 5.7L Vortec, Z-71 with 80K miles. Last Sat I started it up and white smoke bellowed out the left tailpipe. I suspected a blown head gasket. Took it to the garage and they confirmed. Repair claim consisted of gasket replacement, turned both heads, new bolts, plugs, oil, coolant. I picked up the truck on Thur, drove less than 2 miles and with no warning a loud knocking sound came from under the hood. I immediately pulled over and inspected to find a puddle of oil under the ingine and a rod protruding from the oil pan. I am almost certain that this problem is a result from something that wasn't repaired correctly when the head gasket was replaced. Can you please provide insight as to why a rod was thrown after only driving less than 2-miles at low speed. Your promt reply would be greatly appreciated. Thank you much!

1 Reply

BURRBRIAN

MECHANIC
158 POSTS

By "turned" do you mean you had the heads shaved on the block side? If you did was the piston - to - valve clearance checked? Normally contact between the two would result in broken valve, bent pushrod or a hole in the piston but I guess it might be possible to have this result under the right conditions. Anywat, somewhere along this line would be where I would start searching for the cause of the thrown rod.
Just replacing the head gasket they shouldn't have had to loosen the rod bolts. Is the rod broken or come apart at the cap on the big end? Too coincedental foor me to think that it's not related to the work you had done, though. Goo back to shop and find out just exactly what was done. Bummer! :Evil: