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Discussion Starter #1
Noisy Lifters...

69' Pontiac 400 rebuild - stroked - 462.
Bored 30' over (from stock)
Block zero decked
Eagle 4340 forged crank (clearanced)
Forged H beam rods
Ross dished pistons
9.5:1 compression
Melling 54ds oil pump
#62 255-265cfm 75cc's CNC ported heads set for Hyd. cam filled crossovers
Pontiac iron intake manifold ported
Hydraulic cam 230/236 dur @ .050" lift .590"/.592" lift with 1.52 ratio rockers 112 lobe sep
Comp cams 857-16 roller lifters
Smith bros. 8.850 pushrods
PRW 1.52 stainless steel roller rockers
Bop .500 dist. gear
Comp cams short poly locks
850CFM rebuilt Rochester carberator
Timing - 12-14 initial/ 36-38 total
TH400 automatic transmission
3.23 rear end
180' - 200'F running temp.
10/30 oil

Cold start is great with no noise, sounds like an American built sewing machine. When the engine temp. reaches 180' or so I get a very annoying lifter noise - more apperent at off throttle and traffic light idle in gear and nuetral. 850-950rpm.

I contacted my head rebuilder (great guy! SD performance) and he said to make sure preload on rockers is 3/4 past zero lash. So I performed the preload. The existing preload was 1/4 - 1/2, so I adjusted to 3/4 turn past zero lash as per recommendation.

Upon start up and drive around the neighborhood dropping a few hot suppers! Lol (PJ) it was awesome!! Quiet! ...Right on... she's good! Well not really..... The next few drives and now the lifter noise is back to where I started.

I now have 350 miles on rebuild.

My engine builder warned me about comp cams roller lifters being manufactured off shore, reputable company like many others but possibly this product suffers the off shore curse?

Oil galleries were cleaned and front lifter bore galleries were tapped with new bolts.

Have any of you experienced the same issue? Cause I can't stand this noise!!!
 

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Yes and my mistake was just readjusting the lifters and not backing them off to inspect the pushrods.
The lifters were eating the ends of the pushrods because the cam lift and spring pressure called for hardened chromemoly pushrods.
I had to pull the engine, flush the block and replace all the bearings and new rings.
I would pull the covers and inspect the pushrod ends.
If I would have done this I would have caught the deformation before they actually crumbled sending the pieces into the bearings I could have saved a lot of time and money.
 

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Discussion Starter #3
GR, I actually regret not pulling the rods to inspect during preload work.

My third oil change after rebuild (yes I'm crazy with a third oil change after 300 miles) revealed some brass/metallic contents amongst the oil. So I am willing to pull the motor if need be.

Thanks.
 

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I didn't know WTF I was doing and relied on "experts" that knew even less than I did.
I even called Comp Cams and the rep didn't tell me about the pushrods.
I did more research and called my second engine builder and told him I was going to order the proper springs for my cam but he confirmed the part number and had already ordered the proper springs.
I wasn't told about the rods and he had already installed the new set of stock rods which I promptly bent both of them in #3 .
I had to go to the Comp Cams website to look at the full kit to determine the proper rods I needed.
The first builder CVMS just used the cam and lifters, didn't do anything to the heads that I had paid for and the old springs the stiffest ones were 62 pounds when they should have been 117.
He didn't use the stock rods I had sent with the engine and just used a mismatched bunch of used crap he pulled from his used parts pile.
The only problems I had with my restore were related to the stuff I couldn't do and depended on "experts" who really just took my money and left me to do the research and redo the stuff they actually knew nothing about.
You will know for sure if there is damage when you see the loss of oil pressure.
Thankfully I pulled the engine before there was any damage to the crank journals and it only required polishing.
 

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Discussion Starter #6
Update:

Replaced my radiator core and running much cooler temperatures. Lifter noise is gone!

I suspect my running temps were much hotter than I thought. I was using a laser temp gun to measure temperature last summer.

Installed temperature and oil gauge over winter. My thought is the oil got way too hot and became thin - thus lack of oiling in those hard to get to lifter areas.
 
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