Grinding, " diesel " noise under valve covers

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10-4! Now,.she cruises ( or did, dammit) at 180 or so, In Tampa heat. So, hook up the water pump, and idle her to 180? While monitoring? It'll be in the driveway, not moving. I have a feelin, if I get er to 180, without the WP. I'm have some more issues..
 
pishta said:
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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Ok.Dig that! Now I get it! Thanks!
 
RustyRatRod said:
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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Much Appreciated Rob! Im not sure what you are thinking, but remember you mentioned Piston slap... not sure if that's the current theme. I'm hoping it's piston slap or something else, besides a tore up.wrist pin, bad bearing, scuffed pistons,.ect...in otherwords, something that ain't damaged that i caint, under current situations, ever get fixed. Thank You Brother!
 
Ironracer said:
Much Appreciated Rob! I'm hoping it's piston slap or something else, besides a tore up.wrist pin, bad bearing, scuffed pistons,.ect...
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If it sounds like all eight and it greatly lessens when it gets hot, it's piston slap. If that's what it ends up being, with forged pistons, I wouldn't give a hoot and holler about it. Let it rattle.
 
That's a sound you would have heard from day 1, it wouldn't just onset one day.

So pages later, if this it really all it is...
Remember...
Details details details!
 
My 340 has similar noise when its cold but not as loud as yours and it goes away when it's up to temperature. It has the Keith Black Hyper pistons in it and I let it get good and hot before I beat on it.
 
bobscuda67 said:
My 340 has similar noise when its cold but not as loud as yours and it goes away when it's up to temperature. It has the Keith Black Hyper pistons in it and I let it get good and hot before I beat on it.
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They must be around .004-.006
I like them on the street at .003-.0035
 
MOPAROFFICIAL said:
That's a sound you would have heard from day 1, it wouldn't just onset one day.

So pages later, if this it really all it is...
Remember...
Details details details!
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My sat had 2.5 " pipes, into thrush welded muffs, dumping before the axle... may have never heard it. But I have had this car for a year. Got it running last summer... my Bro says it wasn't there. I'm not sure anymore.. rained out today. Gonna pull fuel pump in a few
 
I had a Chevy 350 block given to me in my early 20s. Four bolt block already .060 over. Cylinders measured well within spec for taper.....but were an honest .065-.069 over. LOL I broke the glaze and assembled it with those old school TRW 12.5 domed pistons and open Chamber heads. Got like 10.7. It rattled like a 1st gen Cummins cold, but that was a runnin little small block. It toted my 69 Chevelle around with authority. lol
 
i had a "diesel" type noise in my LA Stroker. it didnt just show up one day. it was always there but it got loud enough to notice. could never figure out what it was . long story short i had to dismantle the engine . i found that the cam bearings were wiped out. this was originally a blueprint engine with low miles. cam bearings were bad enough that the chain was loose. when i replace d the cam bearings i never heard that noise again. ??????
 
golden boy said:
i had a "diesel" type noise in my LA Stroker. it didnt just show up one day. it was always there but it got loud enough to notice. could never figure out what it was . long story short i had to dismantle the engine . i found that the cam bearings were wiped out. this was originally a blueprint engine with low miles. cam bearings were bad enough that the chain was loose. when i replace d the cam bearings i never heard that noise again. ??????
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How did you end up finding out? I'll take the long story, if you have time!
 
i had Keith Black Hypereutectic pistons. (this is what Blueprint used in those days) recommended ring gap on a 4" bore was 26thou. apparently many engine builders have experienced the same problem i had in that the top ring would expand under heat and butt , causing the top of the piston to break off. most engine builders recommend 32thou now with those pistons! this is what caused me to dissasemble the engine. i still don't understand why the cam bearings were so worn out. but that diesel noise has not reappeared. and i race the car 12.5 sec at our local track.
 
pishta said:
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.
View attachment 1715810228
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What I did find that the pump arm freely moves 1/4" laterally, at the end of arm...
 
Ironracer said:
Says file too large... dammit
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if you are talking video you have to process it to a smaller file format. basically put it on youtube and post the link delete when done...oh and the engine? grinding under valve covers metal to metal no oil?
 
No Sir. Was a video of the car running. But the fuel pump.arm.is loose by 1/4"! I can grab that suckered and, with No Problem,.wiggle it back and forth.. Praying that's it
 
hold up. your fuel pump arm has 1/4 lateral movement..side to side? F that pump! it should have no side to side movement and of the cam cog is lobsided(loose) it will have possibly caused that movement. Try and start motor with no fuel pump. should idle for 20+ seconds on a full bowl, enough to listen for grinding noise without your fuel pump (maybe making it!)
 
can you shoot a video in the fuel pump hole while your holding a flashlight and bumping the starter relay with your 3rd arm? that would show you a possibly wiggling timing chain cog.
 
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