Need Help With Engine Knock
#11
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,052

So I'm going to school to be a diesel mechanic and we share a building with the auto tech and today the auto tech instructor took a look at my blazer and seems to think it's a thrust bearing because the harmonic balencer is moving a little bit. Can anyone agree with this judging by the sound in my video? If it is a thrust bearing I'm just gonna run it till she blows
Your oil pressure does not seem reasonable for hot idle. At idle in drive warmed up 20 miles mine is 25psi with a brand new engine. It was about 10psi when bearings were bad. This is with 5W30.
You did not mention if your SES light is operational. Have you read the codes? If bearings are bad my experience is that false misfire codes get set and the light is on all the time.
Personally I can't condone driving anything until it drops. If bearings you will probably not get many miles out of it and it will probably end up leaving you on the side of the road with a subsequent tow bill.
Last edited by LesMyer; 01-29-2016 at 07:46 AM.
#12
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Join Date: Jan 2016
Posts: 19

I can't view your video, but thrust bearing clearance runs around 0.005". This means there should be no perceptible movement fore/aft for the crankshaft. If you can see it move or hear it clunk when prying forward/back (careful about plastic cover), it is too much. Doubtful that a thrust bearing would go out all by itself, after 100,000 miles. Bet other bearings are involved too.
Your oil pressure does not seem reasonable for hot idle. At idle in drive warmed up 20 miles mine is 25psi with a brand new engine. It was about 10psi when bearings were bad. This is with 5W30.
You did not mention if your SES light is operational. Have you read the codes? If bearings are bad my experience is that false misfire codes get set and the light is on all the time.
Personally I can't condone driving anything until it drops. If bearings you will probably not get many miles out of it and it will probably end up leaving you on the side of the road with a subsequent tow bill.
Your oil pressure does not seem reasonable for hot idle. At idle in drive warmed up 20 miles mine is 25psi with a brand new engine. It was about 10psi when bearings were bad. This is with 5W30.
You did not mention if your SES light is operational. Have you read the codes? If bearings are bad my experience is that false misfire codes get set and the light is on all the time.
Personally I can't condone driving anything until it drops. If bearings you will probably not get many miles out of it and it will probably end up leaving you on the side of the road with a subsequent tow bill.
So are you saying my oil pressure is too high? If you're able to watch the video I show my oil pressure as well. I'll try to get under it today and wiggle some stuff
#13
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Join Date: Jan 2016
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Also my ses works but is not on. No codes either
#14
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,052

Not at all - just seems very high for idle in drive fully warmed up. What oil? What RPM. Mine idles at 550 in Drive.
SES light works and is not on with no codes - that is very good.
My thrust bearing was somewhere around 0.025 clearance if I remember correctly. I could get the crank to make a clunk by pulling and pushing my harmonic balancer back and forth. Be careful with the plasic front timing cover.
I'll try the video again. Anyone else able to view it?
Last edited by LesMyer; 01-29-2016 at 10:22 AM.
#15
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Join Date: Jan 2016
Posts: 19

It's penzoil 5w 30. I don't have an rpdm guage on mine but I'd guess it's around 700 rpm in drive. What does your temp guage read fully warmed up? Mine is around 180 or 190
#16
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Join Date: Oct 2014
Location: North Central Indiana
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Got the video to play. Had http://https:// at the beginning of the link got rid of the http:// and it worked. Can't really hear well on my cell phone, but am hearing something. I'll check it out during lunch by plugging into my car stereo.
Also, you can take a sample of your oil into a clean glass jar and let it settle overnight. Drain entire crankcase into a clean pan and take the very first part into the glass jar (I suggest a 1 quart mason jar). If after overnight you see a shiny metal film separating and laying on the bottom as you pour it out of the jar, then you have big problems to fix. After inspection you can pour all the oil back into the engine. Cost = nothing - only work.
Last edited by LesMyer; 01-29-2016 at 10:48 AM.
#17
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Join Date: Jan 2016
Posts: 19

My temp is a little lower in the cold weather. From memory seems in the range that you mention.
Got the video to play. Had http://https:// at the beginning of the link got rid of the http:// and it worked. Can't really hear well on my cell phone, but am hearing something. I'll check it out during lunch by plugging into my car stereo.
Got the video to play. Had http://https:// at the beginning of the link got rid of the http:// and it worked. Can't really hear well on my cell phone, but am hearing something. I'll check it out during lunch by plugging into my car stereo.
#18
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Join Date: Oct 2014
Location: North Central Indiana
Posts: 3,052

Like in the post above, make sure you get a good sample from the first out of the crankcase and let it sit overnight.
#19
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Location: North Central Indiana
Posts: 3,052

watched video in my car. Sounds like horrible exhaust leaks?
#20
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Join Date: Jan 2016
Posts: 19

Is that to check for water? And no I have a thrush glass pack on it so it's a little louder. We're you able to hear the knocking once it was in drive?





