Topic: ENGINE SQUEAKING NOISE

[69cobrajetrugae2]

Video of engine. https://www.youtube.com/watch?v=HJ02wnxyLCI&feature=youtu.be

The noise and not knowing the source is tormenting me. My video camera microphone is not able to capture the sound correctly so I merged another sound file to it.  Both sound files are merged and I don't know how to separate them at this time.

At 11 seconds you will hear the engine start over the existing engine running sound and the squeaking noise is audible.

I thought it was an exhaust leak and now I am not so sure.  Rocker shaft or cam comes to mind, but the noise sounds like it is coming outside the engine.

[67gtasanjose]

Video of engine. https://www.youtube.com/watch?v=HJ02wnxyLCI&feature=youtu.be

The noise and not knowing the source is tormenting me. My video camera microphone is not able to capture the sound correctly so I merged another sound file to it.  Both sound files are merged and I don't know how to separate them at this time.

At 11 seconds you will hear the engine start over the existing engine running sound and the squeaking noise is audible.

I thought it was an exhaust leak and now I am not so sure.  Rocker shaft or cam comes to mind, but the noise sounds like it is coming outside the engine.

It sounds like a rocker arm shaft starving on oil. The rocker arms are fed oil through the shaft they are on, which get the oil from around one of the mounting bolts of the rocker assembly.

Noticing the engine is neat and clean on the outside, has this been rebuilt lately? Did all of the oil passage caps get removed and the passages in the block get wire brush cleaned? Usually this noise was found on very sludged up engines, so unless something else happened, that is what I remember FE (and other) engines making such noises. The rocker assembly tubes can be sludged inside also, I used to dip them in a 5 gal pail of Carb cleaner, 1/2 at a time, to get the insides softened for cleaning them out 100%.  Only other time I heard this noise was on fresh builds that the rockers were not pre-lubed during assembly.

Richard

[carlite65]

agreed on rockers. i once had one do that. problem was too much valve spring psi for the type of cam used.

[69cobrajetrugae2]

I thought about the rocker shafts. I have driven the car a couple of hundred miles since the noise morphed into the present state and there is no difference in pitch.  Can the rocker shafts make this kind of noise for a extended period of time without getting worse?

I have no history on the engine as far as when it was rebuilt other than it has oil pressure of 950 RPM 42 PSIG at 185F oil temp, and 110 PSIG at 2000 RPM 185F oil temp.

Thank you for your replies, I am going to try a few things and will report back.

[Bob Gaines]

I thought about the rocker shafts. I have driven the car a couple of hundred miles since the noise morphed into the present state and there is no difference in pitch.  Can the rocker shafts make this kind of noise for a extended period of time without getting worse?

I have no history on the engine as far as when it was rebuilt other than it has oil pressure of 950 RPM 42 PSIG at 185F oil temp, and 110 PSIG at 2000 RPM 185F oil temp.

Thank you for your replies, I am going to try a few things and will report back.

It would not  take much to change out the rocker arm assemblies with another set to confirm if that was the area of the noise.

[69cobrajetrugae2]

When cranking the engine over with a remote switch the squeak is clear and audible with each crankshaft revolution.

There is no exhaust pressure at this time so it could not be exhaust related, is that correct?

When the engine is running and each cylinder is disabled one at a time, the squeak is unchanged at idle.

That is a good suggestion on the rocker shafts but I would like to determine the cause if possible before tearing into the engine.

Here is a video of the engine cranking.
   
https://www.youtube.com/watch?v=SmILRMlUHtA&feature=youtu.be

I greatly appreciate all of your replies.

[rayms69]

that noise would drive me nuts, hope its not internal, i would try to isolate the noise by using a tube from gift wrapping or pvc pipe. I would think it was in the belts, but im no master mechanic, maybe the other guys are right. hope its an easy fix.

[67gtasanjose]

After listening again, I am sure it is a rocker. Just pull the shaft out and take a look. If they are not sludged up, they disassemble really easily. If you have a worn one, you will be able to tell. If you take it apart, keep the parts in order for reassembly. They do sell remanufactured shaft assemblies, but unless something is completely shot, I suggest rebuilding your own.

Richard

[69cobrajetrugae2]

With the engine running I shoved a large screwdriver with a rag on the end and started poking from under the engine.

The noise went away from "under" the car at 3 and 4 cylinders next to the exhaust manifold.  Ever since I acquired the car there was a slight bubbling while running at this location. I assumed it was a slight external coolant leak at the head gasket, now I am not so sure.

I placed a small paper at the suspect location and it did not wiggle.

The screwdriver with the rag could have muffled a leaking spark plug but I doubt it. I am going to change 1 2 3 4 anyway.

The fire ring at the head gasket could be breached causing the squeak.  That would explain everything.

I am going to see if I can get a compression reading, but it might not be moving enough air volume to notice  pressure drop.

Is it tough to change 1234 head gasket?

Please let me know what you guys think.

[J_Speegle]

..............I thought it was an exhaust leak and now I am not so sure.  Rocker shaft or cam comes to mind, but the noise sounds like it is coming outside the engine.

Just because its easy and quick I would have started with removing all the belts and eliminate the belt driven accessories at the start. Water pump, alternator, PS ....

After that its internal and the search begins. If you can localize it - pulling the valve cover and checking the oiling of the rocker arms would be my next step.

Head and intake is not a big job - but I've never heard a head gasket make that sound


Sort of sounds like my F250 - have had a AC compressor or clutch that has been making that sound for the last 70K   - ya I know   but only at certain times - when its engaged 

[69cobrajetrugae2]

The noise did go away with the rag. It is either a leaking 2 or 3 plug or the head gasket. I am going to JB weld the suspect location now and start it up tomorrow afternoon and see if the noise goes away.  Thank you everyone for your help.
 

[69cobrajetrugae2]

The squeak is gone, for now. Completely.

 The one inch long area that is leaking is just aft of number 3 cylinder viewable from underneath the car.

After examining pictures of blocks and heads it could be a crack from a head bolt thread near the triangle shaped block or head coolant passage near number 3. The fire ring could have failed but after 9 thousand miles since I noticed the pulsating bubbling at the area, there is a logical presumption that if it was the head gasket fire ring, it would have blown open long ago.

 I drive the car at 100% power runs at least 8 times a week for 1 1/2 years. A crack would have been stable if it has terminated at the edge of the block or head.  In addition, the coolant control fiber portion of the head gasket has been redirecting the combustion gasses until recently. A piece of toilet paper held near the leak at idle does not wiggle.  The damn leak is like a musical instrument, high pressure, low volume.

In diagnosing the leak, I soaked a rag and shoved it into the area when the engine was running and the noise was reduced by 90%. Next I cleaned the area with carburetor cleaner followed by brake cleaner. After the engine cooled for 30 minutes and the area was a 180F degrees I paddled some JB wed into the area.  My theory is that the epoxy will cure in the expanded state and not blow off with the heat of operation.

30 hours later, when I am done typing, I am going too encapsulate the first patch with the second patch of JB Weld cold with tiny bits of stainless steel wire mixed in.  Hopefully the hot/cold patch will hold.

My other option is to pull the engine and go through it.  The engine runs strong and sweet and I want to get some more mileage out of it before I do that.

Thanks again for your replies

[Bob Gaines]

Strange . Thanks for the update. That is a out of the ordinary occurrence I will try and remember.

[69cobrajetrugae2]

Bob.

I agree.  In my 40 years of wrenching on cars I have never heard of such a thing. High compression cars are notoriously unforgiving in the area of head to block interface sealing.

A friend suggested not to apply the cold application of JB Weld.  His thought was that adding a cold patch could trap heat on the primary hot patch and to leave well enough alone. I agreed.

I just returned from a 30mile freeway run with 4 WOT events.  I limited the RPM's to 4800 in forth gear and the car performed fantastic.

I have heard of miracle stories using the JB weld and if the patch stands up to the thermal cycles as time passes, my story might fit in that category. I have used it through the years and I keep my epoxy's in my desk drawer away from temperature extremes and always buy a fresh batch for critical repairs.