Grinding, " diesel " noise under valve covers

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Does it do it when you rotate the crank? Fuel pump eccentric hitting the timing cover? Does the crank turn a few degrees before the chain tightens up? Could be whipping to the side of the case?
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Thanks! Went out with the 10". Almost sounds like the lifter valley/ cam chest, but that's with a regular ear. Haven't found anything with the ext. Yet.. did lay hands on the fuel pump. Not sure if they are supposed to have a noticeable "hit" when you grab em w/ the mill rollin.
You put the extension behind the ear. On your skull...brother
 
I'm not the final say, just a prediction.
Maybe you'll see piston to head contact. Idk the motor...but if it was scuffing you can see it from the bottom/ oil pan side.
With a stethoscope you will hear it prominently around the plug area on the cyl head. You won't hear much if at all at the pan rail .
Oh man. It's got an 8 qt pan. And the damn poly motor mounts are not fun on one side. Everything is tight in there. Lol. ( former B body guy) I've owned a bunch of /6 A's. But just drove em. 63 Dart Gt, 71 Demon, a few Dusters,, a 68 Valiant 318...anyway the tip on locating that sonically is much appreciated! So what would cause piston scuff?
 
Does it do it when you rotate the crank? Fuel pump eccentric hitting the timing cover? Does the crank turn a few degrees before the chain tightens up? Could be whipping to the side of the case?
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I haven't tried to spin it manually that far... or do you mean kill ignition, and roll em w/ starter? It a low mile build, w/ all good parts... but that prolly don't mean much. I think I'd hear the Cloyez hitting...haven't checked for chain play yet. NOW, on that fuel pump eccentric, when she's running, I can feel a solid "hit" when I put my hand around pump. Not sure if that is common. But, it's not " un time " w/ " the sound" or how that would transmit...is there a way to test that? Man, that would be a Blessing if that was the case!!!!!!!
 
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if you pull the pump and jam a screwdriver in there and rattle the eccentric around, it should not move on the camshaft. If it does...its loosey goosey. I dont know what the clearance is from the front of the eccentric to the case but if its a few mm's then if the bolt has come loose, the eccentric may be riding the cam key just enough to ride on the inside of the case too and somehow keep cycling the fuel pump. That would be crazy if that was the problem!
 
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Too much timing for too long, spark scatter/bad rotor phasing.
Cool. Motor was on points for 2 years. When I tested the Hi Rev dizzy, I don't think I had enough vacuum to pull in vacuum adv. And I haven't drove her much maybe 25 miles ( after a thrash for the rear suspension, and adding stripes, for a friend's Memorial, and another 18 miles to go to ( now x) moms for Thanksgiving. Other than that, just some 3 -5 jaunts through the area out here. Do you need a better Spark Plug Pic? And Thank You for helping me. I may be screwed
 
if you pull the pump and jam a screwdriver in there and rattle the eccentric around, it should not move on the camshaft. If it does...its loosey goosey.
OK. I know I sound ignorant somewhat, but I'm gonna do it anyway! Lol am I looking to push up and down, in and out, side to side? And how will know if it's moving o the cam? Im a Carpenter. Maybe, sometimes, at best, a " parts changer". Definitely NOT a diagnostic Mechanic/ Tech. Thank God I've always drove Mopars.. I'd be screwed otherwise!
 
Yes, where the pump rod rides on the eccentric...if you can feel that move when your in there, its loose. It should be rock solid in there. also see if you can wedge the scredriver tip between the eccentric and the timing cog...it would all be done by feel unless you can get your iphone camera down there and take a pic in there through the hole. The gear would be moving too as the only thing preventing it from coming off is the lower chain cog being captive behind the balancer.
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No I phone here! Just a Samsung on metro. But it has a camera! Can I just RnR the thing? Or to I have to pull the timing cover? Wonder if I wiped part of the cam.. I'm gonna actually look at a manual for pics so I have a better understanding! THANK YOU SIR!!!!!!!
 
timing cover off.....that means balancer too. Water pump too unless you want to remove the radiator and pull the pump with the case as one piece. Cam should be fine. It may have walked a little but they are pretty wedged in there due to the way the lobes are ground biasing it towards the rear.
 
Come to think about it, the timing cover, and eccentric, were prolly robbed outta a 318 I had layin round. I do not remember buying one, but may rember cleaning one,, and changing the seal w/ a piece of maybe 2" sch 40? and Definitely do NOT recall buying a FP eccentric. But I may have. I don't usually use used wear parts. But I could have been " outta time and money" lol and actually, earlier, I found the sound loudest ( by ear) under carb, over the front top of ( not a valley pan like a big block) the bottom of the Holley Strip Dom.... I Pray that's it!
 
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If the Eccentric was spun, wouldn't lose fuel pressure/ operations?
You'd think. Let me ask this. Let's call it a knock for the sake of naming the noise. Is it one knock or does is sound like all 8? You say it's diesel sounding so that would sound like all 8, right?
 
Yessir, I reckon. I mean, I held my hand over the fuel pump, while running, there was a noticeable "hit" felt that was over the engine shaking, but, it was not " In time " with the Constant " sound " like a bad drummer, practice n syncopation. So, Yes, the only other noise, that Is Not , in the reciprocating mass, on the driver's side, sounds like damn Percy's exhaust gasket a/ header. Just got em last year, right after company changed hands.
 
Yessir, I reckon. I mean, I held my hand over the fuel pump, while running, there was a noticeable "hit" felt that was over the engine shaking, but, it was not " In time " with the Constant " sound " like a bad drummer, practice n syncopation.
What does it sound like when completely warmed up at operating temperature? Does the noise subside any?
 
What does it sound like when completely warmed up at operating temperature? Does the noise subside any?
Honestly, Rob, i haven't got her up to op temp, in a while! Did a shifter, front end, and then caught that **** dizzy issue. However, I was mapping timing the other day, with my gal reading tach, and operating throttle, for a bit. It Seemed to be quieting.. but I wasn't specifically looking for/ at that. And I didn't look at temp ga. But we mapped it, several times, up to, and over 3k
 
Get it completely warmed up. I mean let it sit there and run 30-45 minutes. Till it's good and hot. See what it sounds like then.
 
Well, I have a temp ga on er. Today, running it, the wp was still disconnected. Was maybe 140 on ga. Never ran it really long, at one time.
 
Well, I have a temp ga on er. Today, running it, the wp was still disconnected. Was maybe 140 on ga. Never ran it really long, at one time.
Nowhere near warmed up. If it's what I'm thinkin, it's gonna quiet down significantly when it's up to temp.
 
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