![]() |
Register or Log In To remove these advertisements. |
|
|
![]() |
|
Thread Tools | Display Modes |
![]() |
#1 |
Registered User
Join Date: Apr 2016
Location: Woodstock, Georgia
Posts: 4
|
1986 K10 Engine Noise - Help Needed! What could it be?
Hey everyone, after tons of useful reads on here, Im finally writing my first post. I have a 86 K10 with a 305, Which i think is original, and its not sounding too healthy. I have this noise i cant diagnose. Can anyone tell me what this could be? Where is this noise coming from? I just replaced the fan clutch, thinking that was the issue, but no dice. Still awful noise. Stethoscoped everything I could and didn't find the cause. Any help would be amazing. Thanks!
Here are links to some videos of the noise... https://youtu.be/OTk8F-2MmPQ https://youtu.be/W2-TXK704Ko |
![]() |
![]() |
![]() |
#2 |
Active Member
![]() Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
Posts: 7,947
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Sounds like a dry bearing to me. Most likely the water pump.
__________________
68 GMC 250/3 speed Saginaw p/b p/s 69 Chevy 350/350 currently in pieces still lookin for a cab 06 Trailblazer I just want a vehicle that I can work on, that won't talk to me, leave error msgs or keep track of how I drive... |
![]() |
![]() |
![]() |
#3 |
Active Member
![]() Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
Posts: 7,947
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Forgot to mention... Welcome to the site.
One other thing re. the noise. I usually look for the synchronized sound to a pulley movement. In other words the beat or rhythm of the sound in relation to the revolution of the pulley. Some pulleys turn faster than others and you can isolate it somewhat like that.
__________________
68 GMC 250/3 speed Saginaw p/b p/s 69 Chevy 350/350 currently in pieces still lookin for a cab 06 Trailblazer I just want a vehicle that I can work on, that won't talk to me, leave error msgs or keep track of how I drive... |
![]() |
![]() |
![]() |
#4 |
Senior Member
![]() Join Date: Sep 2005
Location: Lewisville, Nc
Posts: 10,234
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Pull the belts off one bu one and that will help you track it down
__________________
David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube |
![]() |
![]() |
![]() |
#5 |
Registered User
Join Date: Apr 2016
Location: Woodstock, Georgia
Posts: 4
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Cool. Thanks so much guys! Went and got a new water pump today. Will hopefully be able to put it on tomorrow, if it's not raining. When doing, I'll remove belts one by one too and start in between to listen. Will update. Thanks again
|
![]() |
![]() |
![]() |
#6 |
*** That's interesting ***
Join Date: Oct 2008
Location: Pittsburgh, PA
Posts: 2,772
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
If it isn't the water pump, try the alternator next.
__________________
Tom ![]() Chevy by day... 1969 Chevy C30 Rollback Tow Truck -- 383 stroker, 4L80E 2011 Chevy Caprice PPV 9C3 6.0L 1995 Chevy Caprice 9C1 1994 Chevy Caprice 9C1 #3 1995 Chevy Caprice Wagon #2 1995 Chevy Impala SS Mopar by night... 1969 Dodge Charger 1972 Chrysler Newport 2dr Hardtop (27K miles) Plus others... |
![]() |
![]() |
![]() |
#7 |
Registered User
![]() Join Date: Jul 2015
Location: 2nd left past the stump on a dirt road.
Posts: 2,629
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
|
![]() |
![]() |
![]() |
#8 |
Registered User
Join Date: Apr 2016
Location: Woodstock, Georgia
Posts: 4
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Okay, so here's the update. I took the belts off one by one and started the truck to listen after removing each belt. First the belt to alternator, still noise, so not the alternator. Next the ac compressor, still heard it. Last belt is both water pump and power steering, sounds much better, but still something. I replaced the water pump anyways. I put a link to videos below of it running with no belts and running after I replaced the water pump. Damn it....the stupid noise is still there. I got out my stethoscope again...checked power steering pump, nothing. Then wedged it down behind the water pump and put it on the timing chain cover...could something in there be the culprit? It definitely how the most commotion and noise going on.
Any thoughts? Also, seems the truck has to warm up to start making this ruckis...And not sure if this is relevant, but I also hear a sound around 40-50 that sounds like grinding or metal on metal rubbing. It seems that when I step on the gas and the truck down shifts, it goes away, but as soon as I let off its back. Could be a completely different issue, but figured I mention it. No belts https://youtu.be/ooV2jywgCXw Post new water pump, all belts https://youtu.be/QJFwrg3QV7M Thanks again for all the input! I really hope I can get this thing healthy again. This is the first time I've been so stumped with it. |
![]() |
![]() |
![]() |
#9 |
*** That's interesting ***
Join Date: Oct 2008
Location: Pittsburgh, PA
Posts: 2,772
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
OK, now that we've eliminated accessories, we need to dig deeper. That's a weird sound, I was sure it was an accessory. Dang.
The next thing I would suggest is to crawl under and see if it gets louder at the bellhousing area. The flexplate could have debris caught in it. If it is louder there, pull off the inspection cover. See if you see anything rubbing. Or even see if the cover itself is bent and rubbing. Seen that happen multiple times. And flexplate noises tend to transmit through the crank and sound like they are coming from different areas. If it's not that, then yes, it could be the timing chain. The thrust bearing could be shot and your crank could be walking. Or the cam could be walking. Or something could have worked its way under the timing cover. If you are sure it's not coming from the flexplate or transmission area, then I guess you'll have to pull the timing cover...
__________________
Tom ![]() Chevy by day... 1969 Chevy C30 Rollback Tow Truck -- 383 stroker, 4L80E 2011 Chevy Caprice PPV 9C3 6.0L 1995 Chevy Caprice 9C1 1994 Chevy Caprice 9C1 #3 1995 Chevy Caprice Wagon #2 1995 Chevy Impala SS Mopar by night... 1969 Dodge Charger 1972 Chrysler Newport 2dr Hardtop (27K miles) Plus others... |
![]() |
![]() |
![]() |
#10 |
Registered User
Join Date: Apr 2016
Location: Woodstock, Georgia
Posts: 4
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Dang is right!! Such a weird noise. So I have crawled under the truck 3 times over the last few days and listened to everything including the bellhousing and flexplate area. Everything sounds quite normal. The only place I here a louder sound is the timing chain cover. I guess I will try to remove everything and take the timing chain cover off this weekend.
Is there much I can do once in there...or is it sounding more and more like I am going to need an engine shop? Thanks again! |
![]() |
![]() |
![]() |
#11 |
Registered User
Join Date: Oct 2013
Location: Maine
Posts: 2,357
|
Re: 1986 K10 Engine Noise - Help Needed! What could it be?
Grinding and metal on metal sound from timing chain cover eh? I had a 81 C10 305 and the timing chain wore a hole clean through the timing cover. I didn't hear any grinding but once it started leaking lots of oil I found the problem. I was surprised the timing chain didn't jump before that. It was wicked loose.
__________________
76 Chevy K20 76 GMC K15 77 Chevy C10 77 Chevy K10 |
![]() |
![]() |
![]() |
Bookmarks |
Tags |
1986, diagnose, engine, k10, noise |
|
|