Whats the saying? Long story short. Motor started knocking. It sounded like it was coming from the top end and not the bottom. Checked the valve lash on the hydro roller cam and lifters. Was slightly loose, I reset everything at a half turn past zero lash.
Knock went away for maybe five minutes. I decited to pull the intake manifold,Lifter, and cam. Found this...
The Cam, Lifters, Rockers, and Push rods look great. Im thinking that the flakes are from the cam bearings, but im not to sure. Any advice on this matter would be great. Ive started pulling the motor and will tear it down soon enough. Just looking to see what yall think it might be.
Oil pressure was about 65 cold idle, 35 hot idle. and 55-65 at wot. I did notice that the morning the nocking became loud that there was only 15psi at hot idle.
Are you using a bronze dist gear? They're pretty tough, but doesn't hurt to take a look at it. Chance it sheared some particles that ate up that rod bearing. Just a thought.
I am not using a bronze gear. Noticed this afternoon that 3 of the pushrods had been rubbing against the guide plates. Made a fairly significant mark on them. I will have to upload pics this afternoon.
Are you using a bronze dist gear? They're pretty tough, but doesn't hurt to take a look at it. Chance it sheared some particles that ate up that rod bearing. Just a thought.
One big issue with finding flakes inside the engine. Once they've gotten worn enough to flake off, the metallic particles are pumped throughout the engine's oiling system. Every bearing, and oiled surface in your engine now has tiny metallic particles pumped to them, and they go from a little wear to worn out in a very short period of time once this happens.
There's no way I'd simply redo the bottom end after finding metallic particles or flakes in the lifter galley. Time to pull the whole engine down, clean it out, and replace all the bearings, and do whatever else needs attention too. I've been down this road before, and if left unattended you're only a few miles away from a spun rod bearing, or a rod out the side of the block.
That's the plan. Break everything down, rebearing and rebuild with most likely a eagle forged rotating assembly. Haven't decited if I want to punch it out to a 383 or leave it a 355.
Do you know if the cam has a button on the end to keep it from walking forward and back? If not, that might be the cause of the pushrods wearing on the guide plates.
Not sure what Spinn means by two piece guide plates on a SBC? Never seen any that weren't one piece for each pair of pushrods.
Button will do nothing to prevent pushrods rubbing on guideplates, as the lifter is held on location by the lifter bore, cam could move back and forth under the lifter and it won't change a thing for the pushrod.
Split guideplates are a relatively new thing, been on the market about 8 years now....good race engine builders used to have to sometimes split a solid guideplate and reorient them to get best rocker tip alignment with the valve, then weld back together..... but now you can buy the guideplates already split, with a tongue and groove in the middle to prevent rotation out of alignment.
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. The oil filter should have kept most of the metal out of the other bearings and oil passageways... but it got into the oil pump...
. Those copper colored chunks didn't come from the pushrods or guideplates... how many miles on those pushrods? Hopefully a 100,000 or more... If guideplates have sharp edges/burrs in the slots, they should be smoothed at least slightly...
. Those 'adjustable' guideplates been around 15 or 20 years or more... got popular when heads started coming with widened valve guide spacing to allow bigger than factory valves... but the head makers hadn't offered the proper guideplates, yet... I usually weld tack them in position once I get the final adjustment on them... to keep them from coming loose or the halves from rotating slightly... I've also broken guideplates in half and welded them back together to get the pushrod spacing I need... put a steel shim between the broken halves so that the weld doesn't pull them together as the weld cools/shrinks...
If by chance you have a brass thrust shim between your timing chain and block, there is a small chance you could get copper/brass flakes like you have shown but I doubt it.
Hate to say it but what your looking at is the remains of some of your bearings.
Best of success rebuilding your engine.
Bummer! Just went through the same earlier this summer. Lost the rod bearings on #8 (spun) and several others getting ready to go. Had to build a new engine, as my crank was toast.
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