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Clean in there. No wear marks on the valve stem tips. This is a fresh top end. Time to remove an intake retainer and spring to inspect the top of the seals. Careful not to drop in the intake valve.
this is where you feed in a foot or two of clothesline and mush it between valves and piston. And after removing springs slowly turn crank until the valves move enough to check their max travel. And cam lobe lift still needs checked.
Last edited by derekderek; 03-10-2019 at 06:17 PM.
Trying to get the retainers off the valves but I'm overcoming the 100psi I'm pressurizing the cylinder when I try to push down with the valve caps... The valve pops open an gas squirts out of the carb. I think the intake and exhaust valves are sealing good because I hear air and see gas come through the intake when it pops open and air when it pops the exhaust valve. The air shuts down when the valves pop closed
Cover the area with some rags so nothing can fall into the engine. Take a deep socket the size of the top of the valve spring ( spark plug socket should work) and give it a hit with a rubber mallet. It should loosen up or pop off the retainers. Just be sure the socket is big enough to clear the retainers. Once you hit the valve, the retainers should release easier....
The retainers may fall down or pop off when the socket comes up after the hit. The rags will catch the retainers.
Stock boat and truck cams are around .480. 454 HO cam is 510 intake .540 exhaust. This is a modern GM grind that is similar to their performance cams from the era our cars came from. Good power and doesn't beat up a valvetrain. (GM's first priority has always been getting the engine to last the duration of the warranty.) The Crane 741 cam was .632 intake and exhaust. Required 150 lbs spring pressure closed and 450 lbs pressure valve fully open. Guys running stuff like this in performance boats had to pull the heads every 300 hours run time. If your engine was built with correctly matched components and clearanced correctly, you wouldn't have more bent pushrods than straight ones.
Last edited by derekderek; 03-11-2019 at 06:37 AM.
Setting up a ZZ502 cam in a 454 I had to trim .050 off the top of the intake guides to provide enough valve travel. And that is with .527 intake lift. I got enough exhaust travel by leaving out the valve seals.
Focus one one Cylinder (I'd do number 1), install checker springs (Rope method, Air etc.), verify TDC and Timing mark, at TDC check Valve to Piston clearance (if it's less than 0.100" I'd be concerned, but it could still be the other things Spring bind etc.).
Check out the URL, it's got nice step by step process.
Got the springs off #1 cyl... Exhaust has a shim then a rotator then spring Intake has no rotator, has a shim then spring WTF Installed height Exhaust: 2.154 with no rotator or shim Intake: 1.916 no shim... Was no rotator
Nothing is absolute ... It's more likely than not that it is a solid lifter ... Nothing is absolute.
You can disassemble a lifter to confirm.
The main thing I was looking for is wire retainers ... because those are infamous for popping out when a Hydraulic motor has been overreved & lifters "pump up" & dump their guts and bends pushrods etc.
-edit- and on some Hydraulic lifters, it IS possible to delete their wire retainers and retrofit the stronger snap rings.
Nothing is absolute ... It's more likely than not that it is a solid lifter ... Nothing is absolute.
You can disassemble a lifter to confirm.
The main thing I was looking for is wire retainers ... because those are infamous for popping out when a Hydraulic motor has been overreved & lifters "pump up" & dump their guts and bends pushrods etc.
Intake needs to be taken off to get at the lifters.
03-10-2019, 06:16 PM
