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It's the weirdest thing, when I first got my car it had 167,000 km, and it had no bottom end knock whatsoever. Well my car sat out that winter in the garage due to lack of funds to do what I wanted to do with it.
So when I did get it on the road (this is after I completely redid the top end of the motor, block up), I drove it for about 2000 km without a hitch, ran so strong with no noises at all. At this point I decided to get rid of that oil and put in some Mobil 1. And it may be just my memory failing on me, but I believe it was after I put in the Mobil 1 that I started to hear a very slight knock when I was parking my car.
It would only happen when I'd stick the car in reverse and park into my spot. It was not at all consistent, when it first started occuring it hardly ever happened.
Ok so how can I describe it? Well, first off, it sounds like it's coming from the bottom end, it does have that crank sound to it. It only occurs at idle or with very slight throttle, and when it reaches about 1100 rpm you can no longer here it at all. Some how it seems to be aggrevated by putting the car into reverse, when I'd haul into my driveway a move around, and just sit there in drive, it would not happen at all, but when I put it into reverse and started moving around, you could here the knock slightly. And no matter what, there'd pretty much be no getting rid of it after it started, putting it back into drive had no effect. Once again I'd like to mention that with any throttle it completely disappeared, not there at all under load.
Ever since it first started, it's progressively getting worse, it's there pretty often now, but still not always, and it's not even loud enough to the point where you can hear it when you're outside the car.
I hope I've described it good enough, I'd also like to mention that after I noticed the sound was getting worse, I decided to swap out the Mobil 1 with some 5W30 Valvoline, and the condition didnt change at all. The Mobil 1 might not have any effect on it at all, It just seems to all of started around that time.
So what do you guys think it might be? My father (who is a mechanic for like 35 years) said it might actually be the crank thrust bearing. He said he's actually after changing these out while the engine was in some cars, but it's not possible with our cars (came to that realization after I read the GM manual's procedure for removing the oil pan). He has a pretty neat trick for it apparently, he's after replacing crank main bearings by literally spinning them out with the crankshaft while spinning the new one in at the same time. I've never heard or seen it done before though.
Anyways any other guesses at what it could be? Could it be something like the crank sensor causing a knock? It's really weird, You'd think if it were something on the crank it'd be more consistant, or there all the time, but it's not.
Well I might just haul the engine out over the winter and rebuild the bottom end completely. I probably wont do that though unless I find that getrag I'm looking for though, unless it gets bad enough that it really seems like it has to be fixed.
Any input anyone has is welcome,
Thanks
So when I did get it on the road (this is after I completely redid the top end of the motor, block up), I drove it for about 2000 km without a hitch, ran so strong with no noises at all. At this point I decided to get rid of that oil and put in some Mobil 1. And it may be just my memory failing on me, but I believe it was after I put in the Mobil 1 that I started to hear a very slight knock when I was parking my car.
It would only happen when I'd stick the car in reverse and park into my spot. It was not at all consistent, when it first started occuring it hardly ever happened.
Ok so how can I describe it? Well, first off, it sounds like it's coming from the bottom end, it does have that crank sound to it. It only occurs at idle or with very slight throttle, and when it reaches about 1100 rpm you can no longer here it at all. Some how it seems to be aggrevated by putting the car into reverse, when I'd haul into my driveway a move around, and just sit there in drive, it would not happen at all, but when I put it into reverse and started moving around, you could here the knock slightly. And no matter what, there'd pretty much be no getting rid of it after it started, putting it back into drive had no effect. Once again I'd like to mention that with any throttle it completely disappeared, not there at all under load.
Ever since it first started, it's progressively getting worse, it's there pretty often now, but still not always, and it's not even loud enough to the point where you can hear it when you're outside the car.
I hope I've described it good enough, I'd also like to mention that after I noticed the sound was getting worse, I decided to swap out the Mobil 1 with some 5W30 Valvoline, and the condition didnt change at all. The Mobil 1 might not have any effect on it at all, It just seems to all of started around that time.
So what do you guys think it might be? My father (who is a mechanic for like 35 years) said it might actually be the crank thrust bearing. He said he's actually after changing these out while the engine was in some cars, but it's not possible with our cars (came to that realization after I read the GM manual's procedure for removing the oil pan). He has a pretty neat trick for it apparently, he's after replacing crank main bearings by literally spinning them out with the crankshaft while spinning the new one in at the same time. I've never heard or seen it done before though.
Anyways any other guesses at what it could be? Could it be something like the crank sensor causing a knock? It's really weird, You'd think if it were something on the crank it'd be more consistant, or there all the time, but it's not.
Well I might just haul the engine out over the winter and rebuild the bottom end completely. I probably wont do that though unless I find that getrag I'm looking for though, unless it gets bad enough that it really seems like it has to be fixed.
Any input anyone has is welcome,
Thanks
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