Rod knock/spun bearing?
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From: Orange County
Rod knock/spun bearing? There's a clanking noise that sounds like it's coming from my engine. A friend of mine and his coworker checked it out at this shop they work at, but they think it's coming from the exhaust. It sounded kind of like squeaking/clanking/knocking or something, but it wasn't repetitive or anything. Just this afternoon though I started up the car, and the sound was worse. It was loud and repetitive. If I have a rod knocking or a spun bearing, what kind of symptoms would there be besides noise? I can still drive the car.
Biggest thing I can say is take off the valve covers and get yourself a long screw driver. Use the screwdriver as a stethoscope and probe around and see if you can find anything. The next step would be to pull the pan off and check rod play. They should move about .010-.020 side to side, but not be loose around the journal.
If it was a spun rod bearing, the noise will trace rpm's. Does it? When I spun a bearing, It was very very loud, and I noticed that when I pulled the valve covers, the rockers weren't getting oiled evenly, some pushrods had no oil, while a couple were shooting it out. Don't know if that always happens though.
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Take off your serpentine belt and run it.This will eliminate a bad alternator bearing A/C, power sterring, air pump, etc...
A friend of mine had a torque converter come loose once (he forgot to torque it down, DOH!) and it sounded just like a rod knock.
What is the oil pressure like?
What does the oil look like? Take a white sheet of paper and smear the dipstick on it and have a look. If it looks like glitter, that's not good.
A friend of mine had a torque converter come loose once (he forgot to torque it down, DOH!) and it sounded just like a rod knock.
What is the oil pressure like?
What does the oil look like? Take a white sheet of paper and smear the dipstick on it and have a look. If it looks like glitter, that's not good.
Check your cat. The brick in the cat might be broken and rattling around. If it is, it will get worse by the minut like you said. If it is a bearing it would be right with the rpm's and would always be there. My brick broke right after i got my TA and was making horrable noise lol. If the brick is broke youll need a new cat, i gutted mine and put it back on, but i have a 1993 so it's obd1 and only has two o2 sensors and they'r before the cat. If yours is any newer you will freak the comp out i think, the sensors will tell the comp that the cat aint doin **** lol.
If it was a spun rod bearing, the noise will trace rpm's. Does it? When I spun a bearing, It was very very loud, and I noticed that when I pulled the valve covers, the rockers weren't getting oiled evenly, some pushrods had no oil, while a couple were shooting it out. Don't know if that always happens though.
Does the sound go away when you give it gas? Is the oil pressure normal? If the oil pressure if low and the sound goes with the rpm more than likely a spun bearing. If its a rod bearing it will go away when you pull that cylinders plug wire. If the sound goes away with gas or when you say go from drive to reverse its likely a torque converter loose bolt problem. If all that is normal and you think it may be the cat the car will fall on its face while driving and giving it gas.
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My spun rod bearing was very loud and thud like from inside the engine. It was very noticable and matched rpms. The noise you describe does sound like a broken cat but that probably wouldnt sound like its coming from the engine.
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Brett Foote Thread Starter
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From: Orange County
My oil pressure is in the red once the car is warmed up... we're pretty sure the sending unit is just clogged though. We fixed it once already, but I didn't change my oil so we think it just re-clogged. The noise started about a week ago, and you would only hear it once in a while, and it wasn't consistent. As of yesterday, it was much more repetitive and audible. I guess we'll have to start with the cat, which I bought from someone over the forum, but they haven't gotten back to me for a week so I figure I got ripped off...
https://ls1tech.com/forums/negative-...nando2986.html
https://ls1tech.com/forums/negative-...nando2986.html
My oil pressure is in the red once the car is warmed up... we're pretty sure the sending unit is just clogged though. We fixed it once already, but I didn't change my oil so we think it just re-clogged. The noise started about a week ago, and you would only hear it once in a while, and it wasn't consistent. As of yesterday, it was much more repetitive and audible. I guess we'll have to start with the cat, which I bought from someone over the forum, but they haven't gotten back to me for a week so I figure I got ripped off...
https://ls1tech.com/forums/negative-...nando2986.html
https://ls1tech.com/forums/negative-...nando2986.html
A spun bearing will be consistent, trace rpm, and be pretty loud. Sounds like your problem is elsewhere.
I was referring to where the red hash marks starts, not the solid red area. If you check gauges light comes on, I would be concerned. Sometimes the sensor can be inaccurate. You could try to hook up a mechanical gauge and see where your pressure is at.
its the cat. if its been rattling for awhile and is getting worse its just breaking down more and more. your o2 sensors might be detecting the cloggage and throwing the code too. mine was broke for about a week and it still ran fine and slowly lost performance, the tiny holes in the brick will get crossed up and really clog things up bad. if you have an engine light go to a parts store and get it read. If it says it has a bad o2 sensor it is one of the cats.
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It turns out that I do need a new cat, but that isn't the issue. My oil pump is dead/dying and I spun a bearing like I thought. Since school just started back up and I'm going to be busy, I have it in a shop right now. This guy wants $600 to put a new oil pump and bearings, and he's going to check out the crank shaft. I think he had mercy on me.
It turns out that I do need a new cat, but that isn't the issue. My oil pump is dead/dying and I spun a bearing like I thought. Since school just started back up and I'm going to be busy, I have it in a shop right now. This guy wants $600 to put a new oil pump and bearings, and he's going to check out the crank shaft. I think he had mercy on me.
Sounds like a good deal, but i think it sounds way to cheap to be true. If hes basicly gonna pull apart the entire motor check the crank out and replace everything with new parts including labor for 600?
Or is he just gonna pull the pan undo the rod, swap bearings and look at the crank for wear for 600??
Or is he just gonna pull the pan undo the rod, swap bearings and look at the crank for wear for 600??
Sounds like a good deal, but i think it sounds way to cheap to be true. If hes basicly gonna pull apart the entire motor check the crank out and replace everything with new parts including labor for 600?
Or is he just gonna pull the pan undo the rod, swap bearings and look at the crank for wear for 600??
Or is he just gonna pull the pan undo the rod, swap bearings and look at the crank for wear for 600??
Definitely. I'd expect to pay over $2,000 for the machine work alone to get the block fully rebuilt and ready to use. That's bore, hone, align hone, square deck, cam bearings, heat tank, magnaflux, recondition the rods, cut/polish the crank, balance the rotating assembly, slight mill on the heads, valve job, polish the cam, etc.
That doesn't include gaskets and fluids.
That doesn't include gaskets and fluids.