97 Chevy S10 noise from engine

If they told you it's "a loose rod "knob" crank lower end", they're pulling your knob! lol A bad rod "bearing" will make a knocking sound.

wrote: 97 Chevy S10 117k mi

I am the original owner. I change oil every 3000 miles. It runs just as it always has; no performance problems. I had it checked at the dealer for a rattle in the engine. They tell me it has a "loose rod knob crank lower end" and that I need a new engine. I will have another mechanic check it out. Any thoughts? _____________________________________________

Loose rod knob crank lower end ? But seriously.......:

Describe the rattle: the sound of the rattle, the intensity of the rattle, the location of the rattle, what is happening when the rattle appears, when does the rattle quit, does anything change the rattle - something more than, "I have a rattle".

Good luck.

Rodan.

I first noticed the rattle after I had the rear seals replaced. Only heard the rattle when the starter first kicked from the rear of the engine. Recently from the rear of the engine I could hear a slight rattle during acceleration after starting (like a jar of marbles bouncing around inside). It has become louder but still happens starting the truck & only when accelerating.

If this helps this is how the mechanic listed the cause on the work sheet:

Rod Loose Knob crank Low end rattle rear engine

What motor?

On my 2.2, i heard a rattle that i thought was a water pump.

8 bent valves latter, it turned out to be a bad cam chain tensioner that was rattling around and it led to the chain jumping time and killing my valves on a supposedly non interference engine.

Bob

wrote: 97 Chevy S10 117k mi

I am the original owner. I change oil every 3000 miles. It runs just as it always has; no performance problems.

After I had the rear seals replaced I noticed a slight rattle from the rear of the engine when the starter first kicked. And I could hear the rattle during acceleration (like a jar of marbles bouncing around inside). It has become louder but still happens starting the truck & only when accelerating. I had it checked at the dealer and the mechanic said I need a new engine. He listed the causes:

Rod Loose Knob crank Low end rattle rear engine

I will have another mechanic check it out. Any thoughts? _______________________________________________________

"Knob crank" could have meant "Knock crank".

A worn crank bearing will knock when started and knock during acceleration, but get quieter when there is no acceleration. A bad rod bearing will knock when there is no acceleration and get quiet under acceleration. A knock sounds like a hammer rapidly thumping the engine block.

Some loose hardware rattles and jingles under vibration or torque, such as exhaust system parts. Rattles like marbles in a jar could be a failing bearing in a water pump or some other belt-driven accessory. A rattle like a can of gravel could be a sticking fan belt.

Having another mechanic check it out is a good idea. I think you should also go back to the first mechanic and ask him to explain what the thinks is the problem and why.

Good luck.

Rodan.

If it was my truck I'd be headed back to the guy who changed to seals to find out what he did wrong..like leaving out an endplay shim or not properly tightening the flywheel/flexplate.

Chris

has broken loose the casing. Very common problem on this year S10.

If the noise started after the rear seal was replaced I would say you have a loose flex plate or converter bolt. Possibly even a cracked flex plate.