New Engine Noise

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Joined
Aug 8, 2018
Messages
371
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191
Location
California
My Car
72 Fastback - 351C-4V, Fitech EFI, T56 Magnum 6 Speed
After a short spirited run up a local road, I started getting a clacking in the front of the engine. Comes and goes a bit and sounds like it's up front by the water pump or power steering but of course could be under a valve cover. Used my harbor freight stethoscope and really couldn't narrow it down. Maybe a red herring, but recently replaced my thermostat and found a loose hunk of metal under it. So thinking / hoping my new water pump might be failing?

Appreciate any thoughts on this. 

https://photos.app.goo.gl/AhAucLSTSey9tjK3A

https://photos.app.goo.gl/h4k4wHec2Suyjt7d7

 
After a short spirited run up a local road, I started getting a clacking in the front of the engine. Comes and goes a bit and sounds like it's up front by the water pump or power steering but of course could be under a valve cover. Used my harbor freight stethoscope and really couldn't narrow it down. Maybe a red herring, but recently replaced my thermostat and found a loose hunk of metal under it. So thinking / hoping my new water pump might be failing?

Appreciate any thoughts on this. 

https://photos.app.goo.gl/AhAucLSTSey9tjK3A

https://photos.app.goo.gl/h4k4wHec2Suyjt7d7
Did you check the pulleys? The steering pump pulley seems to have a lot of movement.

 
After a short spirited run up a local road, I started getting a clacking in the front of the engine. Comes and goes a bit and sounds like it's up front by the water pump or power steering but of course could be under a valve cover. Used my harbor freight stethoscope and really couldn't narrow it down. Maybe a red herring, but recently replaced my thermostat and found a loose hunk of metal under it. So thinking / hoping my new water pump might be failing?

Appreciate any thoughts on this. 

https://photos.app.goo.gl/AhAucLSTSey9tjK3A

https://photos.app.goo.gl/h4k4wHec2Suyjt7d7
+1 with tony.  I would remove the fan  belt for  the water pump / power steering and see if the noise goes away.  If  so then you know it's one of the two and can go from there.  If it stays then you have a problem elsewhere.

 
Did you check the pulleys? The steering pump pulley seems to have a lot of movement.
It does have a wobble for sure and on my list of things to check fix at some point, but no, haven't checked it for maybe just being loose or something

+1 with tony.  I would remove the fan  belt for  the water pump / power steering and see if the noise goes away.  If  so then you know it's one of the two and can go from there.  If it stays then you have a problem elsewhere.
Thanks, and good call. Funny if it was someone elses car, I'm thinking I would have figured out that if it's an accessory, take the belt off and see what happens, but it being mine I start to panic and think the worse and don't think of the obvious places to start. 

I'll pull the belts later today and see if if it changes. Thanks for the clarity.

 
I doubt if it would be the timing chain, but it could be the fuel pump eccentric installed wrong or the fuel pump arm not maintaining contact with the eccentric and getting slapped by the eccentric on each revolution. I'm assuming you're using the mechanical pump to feed a surge pump for your FiTech. If you're not using the mechanical pump for fuel supply did you remove it and cap the opening? If not, the fuel pump may installed wrong or causing the noise.

 
Thanks Don. It's an electric pump and the mechanical one is removed and capped off.

Harmonic balancer somehow? Replaced that a few months ago and it looks fine, but maybe failing again?  

Getting a bad feeling about this. 

 
looks like your steering pump pulley is dancing...

Watching the first vid a couple of times, the way the pulley moves sidewards and the sound seams to match.
Even if it's not the sound that you're after, that pump is in need of a revision

As the pulley is really tight on the shaft and could not possibly have this kind of play, I bet the bearing behind is the bad guy.

 
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Thanks. I took off that belt entirely and it's still happening. You should be able to see that in the video from this morning that all belts are removed. FWIW - That pully seems a bit tweaked and has a wobble in it. Going to get a replacement at some point, but unfortunately that's not the issue on this one and neither is the water pump or alternator.  

 
The sound changes a lot over time. Sometimes it's completely gone, sometimes it's very loud and clanky and sometimes it seems more like a rubbing sound. I don't really know what I'm looking for exactly, but none of the pushrods or rockers was very lose or anything. I had been wondering about a collapsed lifer, bent pushrod or maybe even broken spring, but that's way out of my wheel house to know what I'm looking at there unless it's super obvious. 

 
Could be me but in the first video's it sounded like the sound went away some when you revved the engine up.   In your second video it sounds like valve lash adjustment.  I'm wondering if you have a lifter failing where at low rpm it's collapsing but at high rpm it's holding  

 
A real long shot here but, are the bolts that secure the pulley to the balancer tight? Chuck

 
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The sound changes a lot over time. Sometimes it's completely gone, sometimes it's very loud and clanky and sometimes it seems more like a rubbing sound. I don't really know what I'm looking for exactly, but none of the pushrods or rockers was very lose or anything. I had been wondering about a collapsed lifer, bent pushrod or maybe even broken spring, but that's way out of my wheel house to know what I'm looking at there unless it's super obvious. 
With the engine running take a hammer handle or block of wood and press down on the rocker above the pushrod.  Do this for each one. If the noise goes away then the lifter is collapsed or the valve lash is out of adjustment.   If it does quiet down adjusting valve lash is fairly easy.   I would do this first and then proceed from there if needed.  

 
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Does the clatter begin as soon as you start the engine, or does it take a few minutes before it starts? If it begins as soon as you start it I'm leaning towards a valve lifter. If it takes a while it may be oil starvation, with the oil pump sucking in air along with oil, and caused by plugged drain holes in the heads or valley.

 
A real long shot here but, are the bolts that secure the pulley to the balancer tight? Chuck
I'll double check that tonight. 

With the engine running take a hammer handle or block of wood and press down on the rocker above the pushrod.  Do this for each one. If the noise goes away then the lifter is collapsed or the valve lash is out of adjustment.   If it does quiet down adjusting valve lash is fairly easy.   I would do this first and then proceed from there if needed.  
OK thanks. I'll give that a shot this evening. 

Does the clatter begin as soon as you start the engine, or does it take a few minutes before it starts? If it begins as soon as you start it I'm leaning towards a valve lifter. If it takes a while it may be oil starvation, with the oil pump sucking in air along with oil, and caused by plugged drain holes in the heads or valley.
It starts right away. If anything it sometimes goes away or gets quieter as you run it, but not always. Seems to be getting more consistent now as time goes by. In my mind that sort of jives with a collapsed lifer but I'm all theory on this stuff and not sure what things should sound like etc. From the valve train, it sure looks well lubricated and has decent pressure. When I started it, oil literally shot out of all the lifters and seemed to be flowing out at a solid rate. 

 
So checked the bolts on the crank pully, pushed down on each rocker at the pushrod as it was running and no change. It's very odd as it changes a lot. Sometimes it's really loud, others it goes away completely. Sometimes it seems to actually be a bit louder after letting off the gas and it's slowing down.

Here's another video, belts are back on, but it's the same with the belts off. 

https://photos.app.goo.gl/uzg2gtkz8h6LBjfJ8

The sound does seem to be coming from the very front of engine. And again it does this with the water pump, power steering and alternator not turning. Really not sure what to make of it or where to even go with this.

Thanks

 
Worst thought is timing chain guides - tensioner [SIZE=15.4px]shenanigans[/SIZE]?

Also Inside that front blue block, just behind your watery impeller, is also the lobe for actuating the fuel pump -- is it fuel pump actuator slap back onto the front lobe.. ....has one recently fitted a cheap and cheerful aftermarket fuel pump (c'mon fess up :classic_wink: ) ? or is it 50 years old in which case one of the return springs no longer has tension and the actuator is slapping around?

Just for information sake... the actuator on the original fuel pumps have spring tension in both directions of the actuator arm... the weezly cheap aftermarket tin-pot one's have only tension back to the lobe - causing slap...the designers, of course, having the IQ of a chair leg and the intellect of a bicycle.  :classic_dry:

 
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Really hard to tell where it's coming from. Check that your distributor cap is fully seated and square on the distributor, as the rotor could be hitting the terminals - and that all the wires are fully engaged.  If it's definitely from the front of the engine, I might lean towards something being up with the timing chain, maybe the cam bolt is backing out. 

 
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