Bad Engine Noise - Water pump??
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From: Friendswood Texas
Bad Engine Noise - Water pump??
When I started my 94 LT1 this evening it made a loud clak-clak noise. A pretty loud clak-clak, not a tick-tick. It was quiet and running great the last time I drove it on New Year's Day. It has 68k on it and hasn't been run hard at all.
The noise appears to be coming from the front of the engine. Could it be the water pump or its drive from the cam?
I removed the right rocker arm cover and idled the engine and everything looked ok as much as I could tell (which ain't much). The rocker arms didn't have excessive play and I couldn't pinpoint the noise there. I didn't remove the left rocker arm cover because it appears you have to remove the alternator - A/C bracket and it was getting late.
The engine idles fine and is not missfiring or anything. I ran it for a couple minutes as my shade tree mechanic friend and I tried to diagnose the problem. The noise was getting louder.
I live in Clear Lake, south of Houston. Can anyone recommend a good mechanic if it comes to that? I could handle replacing the water pump but anything deeper is over my head.
Thanks for your help!
The noise appears to be coming from the front of the engine. Could it be the water pump or its drive from the cam?
I removed the right rocker arm cover and idled the engine and everything looked ok as much as I could tell (which ain't much). The rocker arms didn't have excessive play and I couldn't pinpoint the noise there. I didn't remove the left rocker arm cover because it appears you have to remove the alternator - A/C bracket and it was getting late.
The engine idles fine and is not missfiring or anything. I ran it for a couple minutes as my shade tree mechanic friend and I tried to diagnose the problem. The noise was getting louder.
I live in Clear Lake, south of Houston. Can anyone recommend a good mechanic if it comes to that? I could handle replacing the water pump but anything deeper is over my head.
Thanks for your help!
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Re: Bad Engine Noise - Water pump?? (Doug in Texas)
You can get a piece of tubing long enough to hold one end on the water pump and the other up to your ear. (Keep it away from moving parts) If something is wrong in there you will hear it. I actually have a stethoscope I got from my doctor that I use for diagnosis on the car. It could also be the belt tensioner or pulley, or even an alternator. I have no idea about a mechanic in Houston as I live in Connecticut. Go up to the Member Locator and punch in your zip, then e mail someone close to you. If you can replace a water pump I see no reason you can’t replace anything else. Diagnosis is 75% of the job, nost of the rest is a piece of cake. Just replacing parts. Usually 75K is the built in obsolescence point for a water pump, so it sounds like you are on the right track.
[Modified by JonM, 12:55 AM 1/7/2002]
[Modified by JonM, 12:55 AM 1/7/2002]
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Re: Bad Engine Noise - Water pump?? (Doug in Texas)
I have recently developed a similar noise on my 89 L98 engine. Mine comes and goes. Sounds somewhat like what a diesel engine would make. When I took it to my mechanic, it wasn't making the noise. He thinks it is a sticking valve lifter.
I tried to time the noise frequency as compared to the rpm's. That will give you some idea of what might be the source.
I tried to time the noise frequency as compared to the rpm's. That will give you some idea of what might be the source.
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From: Friendswood Texas
Re: Bad Engine Noise - Water pump?? (Doug in Texas)
I pulled the front cover off the water pump and you can rotate the impeller back and forth 10 degrees or so. Does anyone know if this amount of movement is normal? There's no axial movement or side to side movement.
As you can tell I'm hoping my clak-clak is the water pump. I don't want to have to fork out big cash-cash to fix my clak-clak. And, it's supposed to be sunny and 70 this week, so it's definitely top down weather and it's much more fun to be able to actually drive with the top down than it is to just sit in the driveway with it down.
And if I could figure out how to insert one of those goofy faces here, I would, but when I drag them on to here nothing happens. So i'll just write it. frowny face, green face with a groaning look
As you can tell I'm hoping my clak-clak is the water pump. I don't want to have to fork out big cash-cash to fix my clak-clak. And, it's supposed to be sunny and 70 this week, so it's definitely top down weather and it's much more fun to be able to actually drive with the top down than it is to just sit in the driveway with it down.
And if I could figure out how to insert one of those goofy faces here, I would, but when I drag them on to here nothing happens. So i'll just write it. frowny face, green face with a groaning look
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Re: Bad Engine Noise - Water pump?? (Doug in Texas)
The way I discovered that my belt tensionsor was that it started eating up the belt. Check your pulley and see if there is any residue. Good luck Oh, just click on the smiley that you want to add and it will be added at that point.
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Re: Bad Engine Noise - Water pump?? (Doug in Texas)
Can you tell how fast the clack-clack is?
Does it clack once for every engine revolution, or twice?
Notice any coolant sprayed on the underside of the hood above where the belt is? That's a dead giveaway of a failing water pump.
The 10 degrees in play might just be play from the coupler between the cam and input shaft, but I don't remember mine having any play at all. There might be some play if the little rubber o-rings are dried out and flattened though.
Also take a listen under the engine. Engines are pretty funny about sound resonance, which means a sound in one part of the engine can appear to be coming from somewhere else. That's why it helps to use a stethoscope or piece of tubing to listen to specific parts. I had a thump-thump sound that seemed to be coming from the bottom end but it turns out I had a chunk of rubber missing from my belt.
[Modified by Thud, 8:14 AM 1/8/2002]
Does it clack once for every engine revolution, or twice?
Notice any coolant sprayed on the underside of the hood above where the belt is? That's a dead giveaway of a failing water pump.
The 10 degrees in play might just be play from the coupler between the cam and input shaft, but I don't remember mine having any play at all. There might be some play if the little rubber o-rings are dried out and flattened though.
Also take a listen under the engine. Engines are pretty funny about sound resonance, which means a sound in one part of the engine can appear to be coming from somewhere else. That's why it helps to use a stethoscope or piece of tubing to listen to specific parts. I had a thump-thump sound that seemed to be coming from the bottom end but it turns out I had a chunk of rubber missing from my belt.
[Modified by Thud, 8:14 AM 1/8/2002]
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From: Friendswood Texas
Re: Bad Engine Noise - Water pump?? (Thud)
Thud,
Thanks.
I used a stethoscope on the engine and the noise was so loud that it was hard to tell where it was coming from but it was definitely much louder at the water pump and front of the engine.
If I had to guess, I'd say the sound corresponded to the camshaft rotation. As I was watching the rocker arms pivot, the noise seemed to be at the same frequency.
At this point I think I'm going to change the water pump and inspect the drive gear. :confused:
Thanks.
I used a stethoscope on the engine and the noise was so loud that it was hard to tell where it was coming from but it was definitely much louder at the water pump and front of the engine.
If I had to guess, I'd say the sound corresponded to the camshaft rotation. As I was watching the rocker arms pivot, the noise seemed to be at the same frequency.
At this point I think I'm going to change the water pump and inspect the drive gear. :confused:
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Re: Bad Engine Noise - Water pump?? (Doug in Texas)
Doug,
Remove the serpentine belt and start the engine. If the noise goes away, it is either a divit gone out of your belt, the belt tensioner, the power steering, or the altenator.
The water pump is driven off the front of the cam, so you won't overheat or be able to eliminate the water pump, but you can the other things I mentioned.
:seeya Purp
Remove the serpentine belt and start the engine. If the noise goes away, it is either a divit gone out of your belt, the belt tensioner, the power steering, or the altenator.
The water pump is driven off the front of the cam, so you won't overheat or be able to eliminate the water pump, but you can the other things I mentioned.
:seeya Purp
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From: Friendswood Texas
Re: Bad Engine Noise - Water pump?? (PurpleC4)
Thanks for the suggestion, Purp.
I removed the serp belt and it was in good shape. I ran the engine w/o the belt and the noise is still there. Two of my mechanically inclined neighbors were sure the problem was a stuck lifter. We removed the rocker covers and ran the engine and they both did their checking and they think the lifters and rockers are in good shape. They both commented on how clean the engine was and how good ut appeared to be running. The water pump appears to be ok. There's no unusual play in the impeller.
Should I do something like remove the water pump, disconnect the coil and crank the engine to try to eliminate the water pump?
One thing about the noise is that it's starting to sound expensive.... :( :cry
I removed the serp belt and it was in good shape. I ran the engine w/o the belt and the noise is still there. Two of my mechanically inclined neighbors were sure the problem was a stuck lifter. We removed the rocker covers and ran the engine and they both did their checking and they think the lifters and rockers are in good shape. They both commented on how clean the engine was and how good ut appeared to be running. The water pump appears to be ok. There's no unusual play in the impeller.
Should I do something like remove the water pump, disconnect the coil and crank the engine to try to eliminate the water pump?
One thing about the noise is that it's starting to sound expensive.... :( :cry
