engine knock/click

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hybrid_b18

crew chief
yO guys I have a 99 ls that sat for a winter in a un heated garrage. I did the swap in the late spring and have been driving around with this knocking or clicking sound coming for the bottom of the block. the motor has under 40K and before it was started oil was poured into the combustion chambers for extra comfort to the rings.

At first I thought it was a detnation problem so i had my car timed like 3 times and still no change. my head was ported and polished and thought it was my lifters but wasnt that. A buddy of mine told me that it could be my crankshaft to rod bearings.
Also, I noticed that when timing, whenever i reved the motor past idle(which is 850 rpm) timing was way off. is that normal???

yO, any ideas and knowledge is power, and welcome so let me know what you guys think.

peace out stay black ;)
 
When I spun a bearing in my car I had a knocking sound comming from the bottom of the block. as the rpms would rise the noise would get louder and there was also a noticeable power loss at the high end. There are two way that I know of to check if it is a spun bearing 1. if you have a good mechanic he should be able to use listening tools to tell you what it is. 2. if you want to see for yourself drop your oil pan and check the bearings from there.
 
the trick to finding which rod is knocking is do this.
with the car running, pull out the spark plug wire to #1 cylinder (pull it out quick, it will ground into the head :) ) if the knocking stops, that is the rod bearing that is going out. if not, plug it back in (quickly again). pulll #2, repeat until you find the cylinder where the knocking stops.

and yes, you only check timing at idle, when revved up timing will change.
 
Originally posted by reckedracing@Aug 6 2004, 12:19 PM
try retarding the timing all the way and see what happens...
[post=373385]Quoted post[/post]​



what will max retard do?
 
Originally posted by B16@Aug 6 2004, 12:42 PM
the trick to finding which rod is knocking is do this.
with the car running, pull out the spark plug wire to #1 cylinder (pull it out quick, it will ground into the head :) ) if the knocking stops, that is the rod bearing that is going out. if not, plug it back in (quickly again). pulll #2, repeat until you find the cylinder where the knocking stops.

and yes, you only check timing at idle, when revved up timing will change.
[post=373394]Quoted post[/post]​



thanks man i moght try that. have you done it yourself or just know what to do?
and yeh thats what I thought about timing. I know to check it at idle at normal opperating temp, but my car idles sort of high compared to my last LS. Any sugestions about that?
 
Originally posted by spydy43@Aug 6 2004, 11:00 AM
When I spun a bearing in my car I had a knocking sound comming from the bottom of the block. as the rpms would rise the noise would get louder and there was also a noticeable power loss at the high end. There are two way that I know of to check if it is a spun bearing 1. if you have a good mechanic he should be able to use listening tools to tell you what it is. 2. if you want to see for yourself drop your oil pan and check the bearings from there.
[post=373342]Quoted post[/post]​


yeah thats exactly whats going on. what should I be cheking for? have never really seen a spun bearing before. thanks for the info mang.
 
idle should be about 750 rpms.

Your timing does change off idle.


A spun bearing knock is hard to miss. It makes a ton of noise once it's going hard.
I doubt a 99 would spin a bearing unless it were starved of oil or beat really hard.
 
so what can i do to fix the idle? and i tried that pulling the plugs one at a time to see if it stopped and that did not work. yea i didnt think I would have spun a bearing. its a 98 (sorry) but it still has less than 40k and the previous owner babied the hell out of it.

i dunno guys, I know i said that someone checked out my top end but do you think it could be lifters, or valves? im stuped and I dont wanna take it to some over priced tech when I can do the same shit.
 
i was under the assumption that it wasn't a bearing causing your problem...

sometimes the knocking is caused by detonation, so retarding the timing would cause the detentation to stop, and you would then know its not a lower end problem...
 
Originally posted by reckedracing@Aug 9 2004, 11:44 AM
i was under the assumption that it wasn't a bearing causing your problem...

sometimes the knocking is caused by detonation, so retarding the timing would cause the detentation to stop, and you would then know its not a lower end problem...
[post=374312]Quoted post[/post]​


okay i got ya, yea i tried to retard all the way already and I can still hear the problem. so we can rule out detonation, right?

so i guess ill try a valve adjustment, anyone know any how to forums for this? I have access to the tools and just need to know specs and how to.
 
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