Hey guys,

I got an 85 TA and when i turn the car on i hear this knocking coming from the block. I can't hear it as much when i rev the engine but it stands out when the car is at low RPMs. I just put some havoline 10w30 so i dont think the oil is the issue. My friend said something about a spun rod or something. What do you guys think?
The knocking goes faster as i rev the engine. They just put this engine in so i don't know.

Also, the butterfly in my intake whistles at idle i dont know how to fix that either.

thanks

 

Hows the oil pressure?

 

waaaaaaaaaaaay high

 

Ya could be a spun bearing..

 

and whats that and what am i facing?

 

Is it a consistent clunk-clunk-clunk noise (main bearing). Or is it like the main bearing noise, but more inconsistant (rod bearing)?

but usually, its the rod

The bearings are seated via small grooves at the ends of the bearings. What this means is the bearings are not meant to spin. Yes the crank spins int he bearings, but the bearings themselves are not meant to spin. When a bearing comes free from its seat, you have spun a bearing.

what it means for the future of your engine. If your engine truly did spin a bearing, you will have to pull the engine and rebuild it. That means complete tear down and rebuild. I hate to be the bearer of bad news, but if it is a spun bearing, there is no 'easy' answer, short of buying a new engine. But then either way, an engine has to come out and an engine has to go back in. You could always buy a new car.

 

it is consistent. it speeds up as the rpms go up. They just put this engine in so i don't know.

 

get an auto stehiscope(spelled wrong) or a long screw driver, put it up to your ear, and find out where the knock is coming from on the engine.

 

i talked to the mechanic that swapped the engines and he said the engine was running fine and that he thinks it could be a bearing but he said to bring the car tomorrow.

 

The way you've described it, I'd say 99% chance that its a spun rod berring... unless it's one of the accessories hitting something (I've seen it happen)

 

i was driving home tonight and i stepped on it pretty good and when i stopped at some the stop lights, i couldnt hear the knocking. I got home and i let the car idle for a bit and i could hear it again.

 

As long as those conditions persist, i would avoid driving that car.

 

Just got back from seeing the mechanic. He said the knocking is not loud/rough enough to be a spun rod. He said it could be a rocker. What do you guys think?

 

92` with a 305 tbi. I have (it sounds like a knock) in the lower part of the engine but it is only after it has sat overnight or all day at work (9 - 10 hours a day). When the engine warms up and I leave and get to the first light.... it is gone. It is puzzling even to my tech buddy. Anyone else have/had this issue?

 

I have... oh wait, its my car now, ha ha almost forgot...

 

probably an exhaust leak. Check the header gaskets first.

With a spun bearing you most typically wont have high oil pressure, and if your knock sensor works, then the car will try retarding the timing so bad that it will end up shutting the car down at idle unless you gas it.

 

i figured i would revive this thread just for amusement. I figured out what the knocking was... it started with the light knocking sound.. then the oil pressure randomly went up and down.. then the oil pressure was none existant.. then the loud clanking sound as i got stuck on the side of the interstate for a few hours...yep spun bearing... now time for god's ultimate creation.. the ls1

 

You might want to try checking your fly wheel and torque converter bolts they might be loose after all you said that you just had the engine changed.Oh just about forgot the whistling is probably a vaccum leak you can test around the plenum by spraying ether or starting fluid around that area while the engine is running but be careful not to use too much might blow something up but if there is a leak in that area the car will idle up by itself when you spray it.

 

oh i already took out the motor, the whistling was the tbi, so i changed all the gaskets and seals, then the motor started that loud knocking sound, i put it on a trailer, took it home and pulled out the motor. the crank was worn 50 thousandths of an inch and the bearing was very thin. You could actually take the rod and move it back and forth... I did find an l98 yesterday that i am going to put in temporarly until i find an ls1.. does anyone know if the tbi intake will work ok with the l98 block/heads??