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Discussion Starter #1
Hello
My newly rebuilt engine has developed a knock. I could use some help to determine the source of the knock. I dont know where to start looking. I took a piece of waterhose and put it on the valve covers and to my ear and tried to listen but it is hard to tell where it is coming from. The bottom end is hard to reach with the hose. Is there a way to see if its the cam and lifters that has gone wrong or if its the bearings in the block? I attach a video where the knock can be heard. Maybe someone can tell by the sound what it is?
I changed the oil today and a lot of metal flakes can be seen, so something is not right. I really need your help guys.

 

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Either way you will need to pull the engine apart if you got metal in the oil. I will guess rod bearings. Hard to tell from a video
 

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Or possibly a cam lobe wore off due to impropper break-in.
 

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If you paid someone to rebuild this motor, then contact them ASAP for what to do next. If you did the rebuild, then as mentioned above, it's time to pull it and inspect. If you're not sure what you're looking at when you tear it down, post pictures and folks here will voice their opinions.
 

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Discussion Starter #5
I did the assembly myself, the machining was done by a machine shop.
What would you start with?
 

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I did the assembly myself, the machining was done by a machine shop.
What would you start with?
Personally, I would call the machine shop and ask what to do. You don't want to void whatever warranty they have if you disassemble it yourself. Of course they might tell you it's all your fault, but at least you checked and might possibly save some money if they did something wrong.

Just my opinion...

Harry Z
 

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Pull each plug wire one at a time. If the knock goes away you got a rod bearing that be loose.
 

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Could be a few different things.... collapsed or sticking lifter, wiped cam lobe, noisy fuel pump, cracked balancer... have you put a vacuum gauge on it to see the needle activity? Almost sounds to me like there a little misfire going on at the same time... if the pistons are "old school" cast (not hypereutectic) and are on the far end of clearance they could even be knocking a bit in a cold engine.

RV6 is on the right track... try shorting the cylinders one at a time to see if it affects the knock. Once you isolate a cylinder you can put a gauge/dial indicator on the rockers to check the cam lobes.
 

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Discussion Starter #11
I checked clearances with plastigauge, they were maybe on the high side but within tolerances.
Can i pull sparkwires while the engine is running?
 

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I checked clearances with plastigauge, they were maybe on the high side but within tolerances.
Can i pull sparkwires while the engine is running?
Better to short the wires to ground using a test light or insulated screwdriver with a jumper wire alligator clipped to the probe/stem and to ground. Slide it up between the boot and wire. Simply pulling the wire can be destructive if you're using a capacitive-discharge type ignition.
 

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I had a knock with metal in my oil after a minor tear down, gasket replacement. Mine turned out to be the timing set I used for my 65 289 was not fully compatible with the spacer/washer that goes on the end of the camshaft. At change level 7 (and from then on) the spacer was built in to the camshaft sprocket on the timing set. Basically, I was double spaced, and when running, the fuel pump eccentric was tapping on the timing cover. The metal shavings in my case were just aluminum from the inside of the timing cover. Still, I pulled the engine and tore it down to discover this. I went on to a full rebuild anyway, just to be done with it. Why not pull your oil pan and take a look at some of the bearings and journals to give you an idea where it’s coming from? I hope you figure it out easily!
 

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Discussion Starter #16
752110


Took the oil pan down today and found this oil galley plug in the pan. I must have messed up tapping it in. Can’t see anything wrong around the crank area. I hope it has taken the route past the timing chain and fuel pump and then straight down ending up in the pan. What do you Think? Could something in that area have chewed on the plug and be causing the knock?
 

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I wonder if that was the old one and your new one is still there. That one looks like it got crushed against something. Several times. I would pull the timing cover and see what's up.
 

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Discussion Starter #18
I tapped them in when the block was bare. There was nothing in the oil pan when i assembled the engine. I’m going to pull the timing cover and i really hope it has gone that way on its way to the pan. That would hopefully mean that bearings and camshaft is ok.
 

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I checked clearances with plastigauge, they were maybe on the high side but within tolerances.
Can i pull sparkwires while the engine is running?
If you want to chance getting zapped you can. One at a time pull a wire then start the car.
 

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I'd pull the timing cover and inspect the chain and sprockets carefully... it looks like the plug may have played pinball in there just a bit.
 
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