Grinding, " diesel " noise under valve covers

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Ironracer

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Hey Everyone, Hope all is well! So, in light of the **** distributor adding to much timing ( I know it's my fault. Never trust advertising specs. Or anyone else w/ a timing light!) It sounds like a diesel truck under my VCs... horrible loud grinding. Scary stuff... don't know if the moly pushrods ate the heavy duty MP factory style rockers? It's a mp 484 cam ( hyd) thanks, Chuck
 
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Oh, bummer! Only thing you can do, is pull the valve covers; and see what awaits. I've seen push rods come up through the ends of the rockers, shaft wear, and of course lots of bent push rods.
 
Could having to much timing cause dead vavle seats? It looks not a clattering valve sound... not a ticking. Sounds like metal rubbing and it's Loud. In all fairness, I have the old Direct Connection repop steel VCs on. Read here they amp noise...shafts were new, as well as everything else when I built her, 12 years ago. Ran points till last year. Switched cars, and gained elect ig
 
I’m thinking you’ll get a ton of guesses as to what it could be over on Facebook. That place is great for getting lots of wild guesses. :realcrazy:
But asked here? Oh, I don’t know maybe Pull the valve covers and start diagnosing!:poke:
 
Can you get a video with some GOOD audio?
 
There some cool cats on FB. But ALOT of dumbasses, and assholes.. I'm pretty much done with Suckerbergs **** show anyhow. It's on an old phone I have, not on this one. And will NOT BE!
 
A long screwdrivers tip pressed on various areas of the heads, the timing cover, etc and the handle end in your ear (like a stethoscope) can possibly help pinpoint the source (before pulling valve covers) initially. Being careful near the fan and belts of course.
 
Damn. Caint find tha keys....I was just out there till it got dark too. Darn CRS syndrome. Getting oldtimers..
 
A long screwdrivers tip pressed on various areas of the heads, the timing cover, etc and the handle end in your ear (like a stethoscope) can possibly help pinpoint the source (before pulling valve covers) initially. Being careful near the fan and belts of course.
It's more like a general noise... kinda from all over. And both banks
 
Sometimes engines with high cylinder pressure can sound like that, especially when they're cold. The pistons will "rock" a little in the cylinders. It's usually more prominent when cold and as they warm up it slacks off some. I had a Chevy 350 that was already .060 over when I got the block. Had like .008" wear on it, but I broke the glaze with a .......you guessed it dingleberry hone and ran chit out of it. It had piston slap so bad when it was cold I got accused of having a diesel in it. lol But it had those old TRW forged pistons in it so I wasn't worried about breaking a skirt. That little bastard ran like scalded dawg too.
 
Virgin bore 340, old trw forged slugs.. funny you say that.... ran her, checking timing curve...came in about 7.... 2 hours later was still warm under hood. Wond6er if she went in heatsink...155 psi cylinder pressure when I checked during the timing fiasco. And what's wrong w/ a dingelhone? I used one on my Ironhead drag bike....a 240 or 280... left a nice cross hatch...besides, if you used one, they can't be all bad!
 
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Grinding noise is metal on metal. Cam moving back & forth, lifters catching on lobes?
 
Grinding noise is metal on metal. Cam moving back & forth, lifters catching on lobes?
Man, I hope not! I took a video, but wouldn't post. It sounds like the rockers are " grinding " or more like a Growl, kinda like a diesel..is it possible the timing of the dizzy caused permanent damage.? Oh , and not trying to get in your business, but how are Things Down Under? The media here keeps us in the dark...
 
Man, I hope not! I took a video, but wouldn't post. It sounds like the rockers are " grinding " or more like a Growl, kinda like a diesel..is it possible the timing of the dizzy caused permanent damage.? Oh , and not trying to get in your business, but how are Things Down Under? The media here keeps us in the dark...
You need to host it on youtube first and then post a link here. This site will not host videos.
 
Wow Cool Rob, Thank You! I've never done that before, but I can think of some good ones. Funny stuff..I had an investor I worked for.rold me I should do it about construction. Said I could make money. Lol. He did say his buddy's gal has one and makes bout 5g a month. Average looking chick, just running around with the kids... crazy. Almost like that " digital art" non- tangible goods...I have a you tube acct ( guess they wanna "see" who's watching what. Lol. I'll do a video, in daytime, and get it on there. Thanks again!
 
Did you pull and disassemble the rockers and shaft or swap from left to right?

The shafts have an index/notch that goes to the bottom toward the front on the driver's side (left side) and toward the rear on the passenger side. The rocker oiler holes will be pointing down.

Pictures with valve covers off would help.
 
Did you pull and disassemble the rockers and shaft or swap from left to right?

The shafts have an index/notch that goes to the bottom toward the front on the driver's side (left side) and toward the rear on the passenger side. The rocker oiler holes will be pointing down.

Pictures with valve covers off would help.
Bought new shafts from advance and new HD rockers from.MP. thing has been together 12 years..
 
Does power steering pump have fluid in it? Sounds like its gurgling.....Just pull the valve covers and start again. perhaps the rockers are hitting the baffles. Wont know until you: Check the pump level and pull the valve covers.
 
Dig that. I'm just concerned that too much advance could cause this? Does sound like p.s. pump. But in both valve covers? Did the washer shim trick. No leaks. But, I HAVE NOT checked the fluid. Car has been parked due to dizzy issues. Just rebuilt front end, so I have to get her to an (Hahaha!) Alignment ( sick joke) shop....built the 340.12 years ago, nothing has changed except the car, ignition,.and the 66 had really loud pipes. So it could have been there all the time. ...
 
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