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Tharf is my hero :read:
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Discussion Starter · #1 ·
The new 383 didnt have the rockers adjusted so I figured id just follow the book I have which outlines a very specific procedure of tightening the bolt just until the pushrod stops rotating by finger and then give it another 3/4 turn. This of course would be done to cylinder #1 when the engine is at TDC. When I adjust it this way, the valve is open. Am I missing something here. Does it have to do with the stroker cam I have in there perhaps? I thought the extra 3/4 turn was to preload the hydraulic things but its just pushing the valves open. I can verify this because if I shine a light in the spark plug hole its more than obvious through the exhaust port. If I adjust the nut just till the pushrod binds, the valve stays closed but the rockers have ridiculous play when I rotate the crank 360 for the next round of adjustment. I even tried rotating the crankshaft for the hell of it to see if the valve would close and to no avail.
 

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HOT AIR BALLOON OWNER
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Stud or pedestal mount?
 

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HOT AIR BALLOON OWNER
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Stock you just torque down and drive on. No valve lash to set.

If it's a stock motor, you have the pedestal mount. Torque is around 20-22ft-lbs usually.
 

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HOT AIR BALLOON OWNER
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This is for later motors I speak of, if you're building a '95 motor it has the ped mount rockers. The link you sent to me was for adjustable valvetrain.
 

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Am I missing something here. Does it have to do with the stroker cam I have in there perhaps?
Stock you just torque down and drive on. No valve lash to set.
both of you have no business under the hood with comments like that. :read:

as far as "missing something", while you've got the engine at TDC, you have it at TDC on the wrong stroke. rotate it 180* and check the position of the valves. both valves should be closed.
 

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Tharf is my hero :read:
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Discussion Starter · #7 ·
No, it is at the proper TDC on the compression stroke. The crate arrived at TDC with the cam dialed in already. The mark on the harmonic is in the proper location on the timing degree bracket. I also have the oil pan off so I have been able to rotate it by hand and verify what stroke its on.
 

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HOT AIR BALLOON OWNER
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both of you have no business under the hood with comments like that. :read:

as far as "missing something", while you've got the engine at TDC, you have it at TDC on the wrong stroke. rotate it 180* and check the position of the valves. both valves should be closed.


Not sure what you haven't been under, but I've been under more motors than you can think... the rockers are torqued down with no lift. It's not rocket science.
 

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Not sure what you haven't been under, but I've been under more motors than you can think... the rockers are torqued down with no lift. It's not rocket science.

son, i've been building engines since you were still playing with GI Joes. built my first small block at 11, and have at least 50 to my credit since then, with several season championships at the local tracks on my engines. apparently i'm doing something right. not to mention the college degree in high performance automotive. :read:

as for having the oil pan off, you cant tell what stroke its on by looking at the crank, you need to look at the cam/lifters/rockers to see that. in the 4 cycles of a 4 cycle engine, the piston will reack TDC at 2 points, first between the compression and power strokes where both valves will be closed, and then again between the exhaust and intake, where both valves will be open. you're on the wrong stroke, rotate the crankshaft 360*, put it back at TDC, and adjust your valves.
 

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HUNTING
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son, i've been building engines since you were still playing with GI Joes. built my first small block at 11, and have at least 50 to my credit since then, with several season championships at the local tracks on my engines. apparently i'm doing something right. not to mention the college degree in high performance automotive. :read:

as for having the oil pan off, you cant tell what stroke its on by looking at the crank, you need to look at the cam/lifters/rockers to see that. in the 4 cycles of a 4 cycle engine, the piston will reack TDC at 2 points, first between the compression and power strokes where both valves will be closed, and then again between the exhaust and intake, where both valves will be open. you're on the wrong stroke, rotate the crankshaft 360*, put it back at TDC, and adjust your valves.
HitmanX was referring to 3rd gen SBC engines. You do know what those are dont you? In the gen 3 and newer engines you dont need to set valve lash. You just torque down the rocker and go.

On the older engines you must set valve lash. And you did a great write up for green95hoe to follow. :shake:
 
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