Pics and videos of the knocking and burnt bearing.
05-18-2009, 09:03 AM
#11
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No, I had a light clicking ever since the TB/valves but that was definintely lifters
[QUOTE=marvgomez;23789598]Chris when I read your original post I wanted to mention how mine sounded similar but when I lost a bearing it all went bad FAST. I think you said yours had been doing it for a long time so I never thought it would be a bearing.QUOTE]
This came about on a Saturday afternoon drive. I stopped immediately and had it towed home. But I feel the same way you did. After looking at the damage I think if I had gone any further on the drive, it could have been the end of that motor.
I thought about getting a replacment motor. It would be very nice to COMPLETELY rebuild one on a stand. Machined head, rebuilt bottom end, fresh powder coat on the block and manifold and turbo....that'd be nice ; ) But logistically I don't think I can do a full motor swap. The shop I work in is on the base and is meant for oil changes, tire swaps, brakes and things of that nature. You can NOT leave a car there over night so they always get a little uneasy when I come in to do work like this. So I think I am just going to swap the crank and connecting rod and replace all the bearings. I have not decided on the piston rings yet. I have never done those before on any car.
This came about on a Saturday afternoon drive. I stopped immediately and had it towed home. But I feel the same way you did. After looking at the damage I think if I had gone any further on the drive, it could have been the end of that motor.
I thought about getting a replacment motor. It would be very nice to COMPLETELY rebuild one on a stand. Machined head, rebuilt bottom end, fresh powder coat on the block and manifold and turbo....that'd be nice ; ) But logistically I don't think I can do a full motor swap. The shop I work in is on the base and is meant for oil changes, tire swaps, brakes and things of that nature. You can NOT leave a car there over night so they always get a little uneasy when I come in to do work like this. So I think I am just going to swap the crank and connecting rod and replace all the bearings. I have not decided on the piston rings yet. I have never done those before on any car.
05-18-2009, 09:56 AM
#12
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I wouldn't expect a failure like that to trip the low oil pressure light, especially while driving. It might at idle, but probably not at any RPM higher than that.
The low oil pressure warning sensor is probably set to trip at around 10-15psi (maybe even lower) and is designed to only go off if you have a catastrophic oil pressure loss. At idle when the engine and oil are up to temp the oil pressure can safely drop as low as 20 psi with out any damage to bearings. A good rule of thumb for minimum oil pressure I've always used is 10psi of pressure for every 1000 RPM the engine is spinning.
Loosing one out of 5 rod bearings that are at the end of the oil passage in the crank would not make a huge drop in pressure. Certainly not enough to drop below 15psi while driving at RPM higher than idle.
The low oil pressure warning sensor is probably set to trip at around 10-15psi (maybe even lower) and is designed to only go off if you have a catastrophic oil pressure loss. At idle when the engine and oil are up to temp the oil pressure can safely drop as low as 20 psi with out any damage to bearings. A good rule of thumb for minimum oil pressure I've always used is 10psi of pressure for every 1000 RPM the engine is spinning.
Loosing one out of 5 rod bearings that are at the end of the oil passage in the crank would not make a huge drop in pressure. Certainly not enough to drop below 15psi while driving at RPM higher than idle.
05-18-2009, 05:26 PM
#13
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I wouldn't expect a failure like that to trip the low oil pressure light, especially while driving. It might at idle, but probably not at any RPM higher than that.
The low oil pressure warning sensor is probably set to trip at around 10-15psi (maybe even lower) and is designed to only go off if you have a catastrophic oil pressure loss. At idle when the engine and oil are up to temp the oil pressure can safely drop as low as 20 psi with out any damage to bearings. A good rule of thumb for minimum oil pressure I've always used is 10psi of pressure for every 1000 RPM the engine is spinning.
Loosing one out of 5 rod bearings that are at the end of the oil passage in the crank would not make a huge drop in pressure. Certainly not enough to drop below 15psi while driving at RPM higher than idle.
The low oil pressure warning sensor is probably set to trip at around 10-15psi (maybe even lower) and is designed to only go off if you have a catastrophic oil pressure loss. At idle when the engine and oil are up to temp the oil pressure can safely drop as low as 20 psi with out any damage to bearings. A good rule of thumb for minimum oil pressure I've always used is 10psi of pressure for every 1000 RPM the engine is spinning.
Loosing one out of 5 rod bearings that are at the end of the oil passage in the crank would not make a huge drop in pressure. Certainly not enough to drop below 15psi while driving at RPM higher than idle.
05-19-2009, 08:59 AM
#16
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No, not yet. I don't think I am going to do the rings though.
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