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Need some engine advice

hunt2elk

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Messing around with the 400-493 stroker in my Super Bee. For those that remember, this is the second go around with this engine for me.
Built by a prominent shop in CA. The first one had a detonation issue. Pulled the motor and sent it back to get a milder cam, and dish pistons with a quench. I lost 20 hp and 4 ft lbs if I remember correctly.
Anyway, got the new motor in last winter and have put 1800 miles on it so far. Have been noticing a progressively worsening valve train noise. Everyone says that hydraulic flat tappet never need service, so I just kept driving it. Today I pulled off the valve covers and was shocked to find the adjusting nuts for #3 intake and #4 exhaust laying in the bottom of the head. #1 and #4 intake nuts were loose. #3, #5, #6 exhaust nuts were loose. The remaining 9 are tight.
What could possibly cause this to happen?
PRW rockers, Trick Flow 240 heads.

20210813_184900.jpg 20210813_184838.jpg
 
Whoever adjusted them didn't tighten the locknut down tight enough.
 
Messing around with the 400-493 stroker in my Super Bee. For those that remember, this is the second go around with this engine for me.
Built by a prominent shop in CA. The first one had a detonation issue. Pulled the motor and sent it back to get a milder cam, and dish pistons with a quench. I lost 20 hp and 4 ft lbs if I remember correctly.
Anyway, got the new motor in last winter and have put 1800 miles on it so far. Have been noticing a progressively worsening valve train noise. Everyone says that hydraulic flat tappet never need service, so I just kept driving it. Today I pulled off the valve covers and was shocked to find the adjusting nuts for #3 intake and #4 exhaust laying in the bottom of the head. #1 and #4 intake nuts were loose. #3, #5, #6 exhaust nuts were loose. The remaining 9 are tight.
What could possibly cause this to happen?
PRW rockers, Trick Flow 240 heads.

View attachment 1151850 View attachment 1151851

mid be very, very pissed. That should not happen.
 
glad they were still in the head, 2nd engine they built for you and I dont think I would go back.
 
mid be very, very pissed. That should not happen.
Especially after paying 15K to a top notch builder. Then having to pull the motor out of a fresh rotisserie rebuild, build a crate and send it back to CA, lose a summer of driving, reinstall, and have this surface. I'm hoping like hell nothing else was overlooked or any damage has been done driving it like this.
 
Good catch. Now take the time and adjust them your self.
Yes, that is the plan. Now does anybody have an adjusting pre load for dummies explanation. Many years ago I did a couple of lash adjustments on a solid flat tappet motors I owned. With feeler gauges it went smoothly. But on this how does a guy determine exactly what a zero lash is? And is the sequence of operation the same as adjusting solids? I can't even remember how I did that....
 
Wiggle the pushrod when you creep up to snug,, and the turn the adjuster how ever far they recommend. on the base circle of the cam. .010= 1/4 turn. .030= 3/4 turn.
Same sequence as a solid.
 
Yes, that is the plan. Now does anybody have an adjusting pre load for dummies explanation. Many years ago I did a couple of lash adjustments on a solid flat tappet motors I owned. With feeler gauges it went smoothly. But on this how does a guy determine exactly what a zero lash is? And is the sequence of operation the same as adjusting solids? I can't even remember how I did that....
Pretty easy. Lifters can vary on how the the preload feels. Take your time. When you get the rocker where you want it loosen the nut while holding the screw. Slowly back it off as you feel the push rod by spinning it between your fingers. I back it off enough that the push rod is loose. Then you can slowly turn the screw until you feel the push rod not wanting to easily spin. Then go down one full turn and lock the nut. Move on to the next rocker. I used my remote start button. Here is a copy from Comp Cams.
First turn the engine in the normal
direction of rotation. Start with cylinder number one (1). When the exhaust valve begins to
move, adjust the intake valve to zero lash plus an additional ½ turn more. Rotate the engine
over again until the intake valve reaches maximum lift and is almost all the way back down.
Then set the exhaust valve to zero lash plus ½ turn. Adjust the valves on each cylinder in this manner until all valves are adjusted. If the engine has nonadjustable rocker arms, a lifter
preload of .020” to .040” must be maintained. See “Non-Adjustable Rocker Arms” section for
 
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What cam and lifters? Reason I said 1 turn is that on a 3/8 fine screw one turn is about .040 preload. On my Hemi that was what was recommended. If you were closer I would swing by and help you.
 
What cam and lifters? Reason I said 1 turn is that on a 3/8 fine screw one turn is about .040 preload. On my Hemi that was what was recommended. If you were closer I would swing by and help you.
I believe he said the lifters are Pro Top Line, which I have never heard of. He told me to go 3/4 turn past zero. I just need to find my notes as to where to have the motor sitting when adjusting which rocker.

20210813_203354[1].jpg
 
I wonder if he meant comp pro magnums.. those are quite a different adjustment
 
So did he actually spec or recommend the PRW rocker arms?
 
Especially after paying 15K to a top notch builder. Then having to pull the motor out of a fresh rotisserie rebuild, build a crate and send it back to CA, lose a summer of driving, reinstall, and have this surface. I'm hoping like hell nothing else was overlooked or any damage has been done driving it like this.

Man , you’re due for good times….I’m sending positive waves all the way….
 
Glad it didn't turn into a major **** show for ya, hope all goes well from here.
 
Bummer! But, rocker adjustment really should be (in my somewhat paranoid opinion) checked every few/five hundred miles during the first couple thousand on a new build, just because things are still getting acquainted and wearing in. They sure *shouldn't* back off like that so soon, but it can happen. When folks say "hydraulics don't need service" they're meaning with a non-adjustable (stock) valvetrain.
If all the parts and pieces are accounted for, I'd say you dodged a bullet there by listening and being quick to respond to the strange noises...you might check the pushrods for bent-ness but if they're okay I'd bolt it back together tighty-tighty and run it.
 
Sorry to hear that a supposedly reputable builder made such a serious....oversight.
I'd be just as interested, (as you might be), to hear how much the PRW rockers were given for side clearance. I have a set on my heads, and thankfully I figured out early that the side clearances called for by PRW are WRONG. They ask for .0015-.0020. Should be .015-.020. Might want to look at that too. Good luck, and keep us posted.
 
So did he actually spec or recommend the PRW rocker arms?
Actually no. At the very start of this rodeo I told him and paid for Harland Sharpe rockers, and this is all in our original conversations and the quote. Was quite surprised last year when I pulled the covers off while we were trying to figure out the detonation issue and saw these PRW's.
 
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