Loud Knocking, COULD REALLY USE YOUR HELP

[sho4sur]

Alright guys, my brother and i were going to the local club and the freeway i opened her up and we topped out at 130 mph. car seems fine. after the club i head to the after party 20 miles away back down the same freeway and car is fine. when i leave the after bar my car has a ticking but only around 3K rpm's! after a while it starts ticking and knocking all the time. at first we thought it was a lifter or rocker cause it was a light ticking then it got louder and acasionally the car felt like it was slipping. then it started to loose power( dropped from 70 mph to 40mph in about 2 miles). I also heard a whinning type noise like my belt was fraying or something? Is this a typical spun bearing? If someone could help me out here or give some ideas on how to go about diagnosing the problem that would be great...thanks much

<small>[ September 27, 2003, 10:12 PM: Message edited by: sho4sur ]</small>

 

[NinjaMike]

No rockers... this is a direct acting drivetrain. Lifters are solid, so they don't stick. What you are most likely hearing is the failure of one or more rod bearings.

Had you stopped the car when it first started doing this, chances for saving the motor would have been significantly higher, but since you drove it long enough for it to start losing power, there is a good chance the crank is scored and you will need at least a new or reground crank.

I really feel bad for you, but I don't understand why people still drive the car after hearing a knock. It's much cheaper to have the car towed and be extremely inconvenienced, than to purchase and install a new motor.

<small>[ September 27, 2003, 10:14 PM: Message edited by: NinjaMike ]</small>

 

[sho4sur]

No. my dumba*s didnt want a cop to pull up. is it worth replacing the crank, or do i just swap the motor? what happens if you just go ahead and replace the bearings even if you cant smooth the crankshaft parts out? should i even bother checking the valvetrain tonight or it that just pointless?

 

[NinjaMike]

I'm not trying to be an ******* . Just an FYI. It just dissapoints me to see more and more of these cars parked at the J yard in pristine condition for this reason.

If the crank is scored and you replace the bearings, they will fail again in a matter of months, perhaps weeks. What you want to do is pop the oil pan off and have a look at the rod bearings and the crank. If the crank is bad, it will be relatively obvious.

IMO, an engine swap is easier and a better idea than a crank swap.