Same block same cam same lifters- safe to reuse? Setting preload?

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cawcislo

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I’m looking to reuse the hydraulic flat tappet cam that came out of the engine that I just rebuilt 318 now stroke to 390. I marked and carefully stored everything so that every lifter goes back exactly where it came from. The lifters are still pumped up. The cam is a Crower 224/224 .465 lift. Car came with the 273 adjustable rockers which I was going to reuse. Iron heads which I am reusing as well. How would I bleed the lifters so I can set appropriate preload? Disassemble them? Thanks for the help.
 
As long as you know what lifter went on which lobe and as long as they still have a good surface, you're good to reuse. As far as draining them I don't have a definite answer. Maybe see if they will drain out in an empty pan by placing the oiling hole down, it might work or it may not.
 
Throw them in on the matching lobes and go. Not worried about the oil in them, just get a new one and use it to check your pushrod length requirement...then order the right ones and stick them in and fire it.
 
drop em in, torque em down and they will bleed down within 10 seconds. rotate crank 90 degrees and wait again. lather rinse repeat.....Hydro lifters are not designed to stay pumped forever, the clearances are just not there. IIRC Johnson white paper stated leakdown test were 2-10 seconds per hydraulic flat tappet lifter. Cant find it now but think of the time the lifters are under load, milliseconds in their cycles. They dont need long retention times.
 
Just like everyone else said, perfectly okay to reuse. But what is the rest of the build like and why no upgrade to a larger cam? These 4 inch stroke motors like to eat, so unless it's got nearly stock iron heads and is going to be used as a tow motor I can't see that small of a cam for it. I know of one of these engines in a 4500 pound extended cab truck with 11.4;1, Eddy heads, air gap, headers, and a Comp XE 274 H. It acts like it wouldn't have had any problems with the XE 274 HL that was intended for it. But that cam was used and the assembler didn't want to run it because it had seen some pretty severe valve float involving a 200 shot of N2O that wiped out the lifters that were run on it.
 
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Just like everyone else said, perfectly okay to reuse. But what is the rest of the build like and why no upgrade to a larger cam? These 4 inch stroke motors like to eat, so unless it's got nearly stock iron heads and is going to be used as a tow motor I can't see that small of a cam for it. I know of one of these engines in a 4500 pound extended cab truck with 11.4;1, Eddy heads, air gap, headers, and a Comp XE 274 H. It acts like it wouldn't have had any problems with the XE 274 HL that was intended for it. But that cam was used and the assembler didn't want to run it because it had seen some pretty severe valve float involving a 200 shot of N2O that wiped out the lifters that were run on it.

right now I’m reusing the whole top end from the 318, which is mild port 360 iron heads, small,port Weiand action plus intake manifold, and the 224/224 .465 Crower cam. This is stage one. I want to run it as is for now and then stage two next Year will include larger port Edelbrock air gap intake, Edelbrock heads, and larger cam possibly a 230/236 or maybe the next step up from that.
 
Stump Puller! That's really the engine that Chrysler needed to put in the full time four wheel drive power wagon with 2.94 gears and 31X10.50s. You're going to love it when you step up to stage two.
 
On hydraulic flat tappet I never bleed the lifters, I find it easier with them pumped up. What the other members have said is correct, yes you can reuse, a cam upgrade would be better but depends on intended use. Myself, I use the old school method to set the rockers on hydraulic flat tappet lifters, which is what I think you were asking, since you have adjustable rockers, Back them all the way out, install everything, Start at number one cylinder, cam lobe in the closed position, then simply take one hand place thumb and index finger on the pushrod, turn the pushrod ever so slightly back and forth, while at the same time slowly tightening the rocker adjuster. Soon as you feel the pushrod stop, stop right there and turn the adjuster another 3/4 of a turn, done. Do that to all.

Now if the lifters bleed down, or you keep turning after you have reached pushrod seat, you will force bleed down the lifter. Be careful with this because you can go to far, and valve might not seat or piston to valve contact could occur Once the lifter pumps up. This is why I like them pumped up, you get more of a solid stop when the pushrod seats. So if they bleed down or you feel you wend too far, no sweat, back off the adjuster, try again, but this time the lifter is not pumped up, so repeat the steps above, soon as you feel a drag, stop because bleed down lifters won’t stop the pushrod from turning like a pumped up lifter would. With your fingers try to move the pushrod up and down, jostle it around a bit with your fingers to check that it is seated and there is no play. If it doesn’t move up down or side to side your good, now turn it 3/4 turn on the adjuster. Done.

As always when done check where your rocker is touching the valve stem, you want it as close to the middle as possible, you can check this by sight at the side, or use chalk to find the wear pattern. If it’s touching on the top of the valve towards the intake the pushrod is too short, if it’s touching Towards the bottom of the valve stem towards exhaust manifold, the pushrod is too long. Middle is just right. Though should not be an issue unless something has changed, like shaved heads etc. If pushrod length is incorrect you will need to measure for correct pushrod length as Moparofficial said.
 
Long as you're 100% sure which lobes the lifters came off of, go for it.
 
I agree that it is OK to reuse. HOWEVER, why stroke an engine and use the same cam. With more cubic inches, I would think a slightly bigger cam would be in order. It would be like putting a smaller cam in the old 318.
 
It'll take about 1000 psi for a lifter to pump itself off a valve seat. The only time a lifter can take in oil is when the check ball is open and that is when there is no load on the 'flat' lifter, ie on any of the other 3 cycles of the cylinder during start up. Once its 'pumped' to zero lash the check ball closes and no amount of pressure will allow any more oil in, the lifter is hydro locked and acts like a solid lifter. No noise, perfect. The only time your going go get a lifter to accept any more oil is if you start flexing pushrods or start floating valves, allowing the lifter plunger to extend past the point of the valvetrains zero lash as there is no valve spring tension on plunger to keep the check ball closed.
 
On hydraulic flat tappet I never bleed the lifters, I find it easier with them pumped up. What the other members have said is correct, yes you can reuse, a cam upgrade would be better but depends on intended use. Myself, I use the old school method to set the rockers on hydraulic flat tappet lifters, which is what I think you were asking, since you have adjustable rockers, Back them all the way out, install everything, Start at number one cylinder, cam lobe in the closed position, then simply take one hand place thumb and index finger on the pushrod, turn the pushrod ever so slightly back and forth, while at the same time slowly tightening the rocker adjuster. Soon as you feel the pushrod stop, stop right there and turn the adjuster another 3/4 of a turn, done. Do that to all.

Now if the lifters bleed down, or you keep turning after you have reached pushrod seat, you will force bleed down the lifter. Be careful with this because you can go to far, and valve might not seat or piston to valve contact could occur Once the lifter pumps up. This is why I like them pumped up, you get more of a solid stop when the pushrod seats. So if they bleed down or you feel you wend too far, no sweat, back off the adjuster, try again, but this time the lifter is not pumped up, so repeat the steps above, soon as you feel a drag, stop because bleed down lifters won’t stop the pushrod from turning like a pumped up lifter would. With your fingers try to move the pushrod up and down, jostle it around a bit with your fingers to check that it is seated and there is no play. If it doesn’t move up down or side to side your good, now turn it 3/4 turn on the adjuster. Done.

As always when done check where your rocker is touching the valve stem, you want it as close to the middle as possible, you can check this by sight at the side, or use chalk to find the wear pattern. If it’s touching on the top of the valve towards the intake the pushrod is too short, if it’s touching Towards the bottom of the valve stem towards exhaust manifold, the pushrod is too long. Middle is just right. Though should not be an issue unless something has changed, like shaved heads etc. If pushrod length is incorrect you will need to measure for correct pushrod length as Moparofficial said.

Thanks very helpful. It’s installed and lashed. Time to drop it in the car and make some noise.
 
I agree that it is OK to reuse. HOWEVER, why stroke an engine and use the same cam. With more cubic inches, I would think a slightly bigger cam would be in order. It would be like putting a smaller cam in the old 318.

It'll just have more bottom end torque.....which might be a good thing.
 
It'll just have more bottom end torque.....which might be a good thing.
You are probably right. My thought is that is seems silly to go to the expense of building a stroker motor if you are not going to take advantage of the extra cubes. But then again, what do I know? That's why they make more than one flavor of ice cream.
 
You are probably right. My thought is that is seems silly to go to the expense of building a stroker motor if you are not going to take advantage of the extra cubes. But then again, what do I know? That's why they make more than one flavor of ice cream.

Hopefully like most builds, it was over-cammed to begin with.
 
You are probably right. My thought is that is seems silly to go to the expense of building a stroker motor if you are not going to take advantage of the extra cubes. But then again, what do I know? That's why they make more than one flavor of ice cream.

Post #6 Tells us his plan.
 
run it easy to change later duration changes rpm ram]]nge- do not just think of feeding mor cubes- see where you are at, get a baswline and talk with shaun @ crower
on the lifters use rev lube but turn thr=e notor over twice stoping every 90 degrees to let the lifters bleed down otherwise you can bend things or tag a [iston and bend valves then remeasure for pushrods
 
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