quit knock, bottom end???????

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josho
Posts: 304
Joined: Wed Jan 14, 2009 5:13 pm

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A buddy of mine has a sr20det swapped 240 that he bought about a year and a half ago that is now for sale. Im considering buying it but it has a very quit knock coming from the bottom end. It has made the noise since he bought the car. It does'nt make the noise at start up but shortly after(maybe 1-2 minutes) it starts to knock a little, its not very noticeable but if you listen you can hear it. I drove it today and got on it, it pulls fine and you cant hear the noise inside the car. Im going to investigate it some more to try and find out what it is. At this point all I can think of is low oil pressure(he also has a crack in his crankcase ventilation tube) or bearings. But I would think the bearings would've went out by now or atleast gotten louder. But it's the same as its always been.....Is there anything I should try to narrow it down and to give you guys more detailed information? TIA


josho
Posts: 304
Joined: Wed Jan 14, 2009 5:13 pm

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And if the bearings are getting worn out, will there be metal shavings on th oil plug magnet?

n240sxfnatic
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Joined: Sun Mar 25, 2007 4:43 am
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josho wrote:And if the bearings are getting worn out, will there be metal shavings on th oil plug magnet?
No bearings are made of copper and other non-magnetic metals so buying a magnetic plug is a waste of money. If the motor is knocking, drive it until it spins a bearing and pick up a longblock for $1000.

josho
Posts: 304
Joined: Wed Jan 14, 2009 5:13 pm

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So you would rather replace a motor then go through and replace bearings or whatever the problem is? Do you think the leaking pcv tube would have anything to with the knocking noise? Im holding on to that hope I guess....

n240sxfnatic
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If it already knocking you have scarred a bearing(s). Its easier for me to just order a longblock than to tear the motor apart (time), have the crank machined remeasured, order bearings, wait on bearings, have block decked, new headgasket and having to wait on parts. Its going to cost u about the same or less to just order a new longblock. Just order a new block now and have it waiting for when this one goes out. Takes maybe 2 days to pull it swap all ur s*** and drop in new one.

josho
Posts: 304
Joined: Wed Jan 14, 2009 5:13 pm

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Makes since. Ill start looking around for a long block. Maybe ill find somebody selling one for cheaper. Thanks


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