Hey guys, I just picked up a formula 357 with brand new, fresh rebult carbed 1996 hp 500's in it. Motors have under 5 hours each on them. Splashed it today for the 1st time before I winterize it. Ran them for about an hour never over 4000 rpm's to let them break in. Everything was going awesome until we where just putiing it back on the trailer and I noticed the the starboard motor had a little tick coming from it. So I opened the engine hatch which made it easier to hear and made it a little louder. The tick flucuates with rpm, and from what I can tell it coming from the top end maybe? These motors where built by a very reputable engine builder, and I have build sheets and dyno sheets also. There where very high dollar parts put back in these motors. Anyways feeling a little sick to my stomach at this point. I am no engine guru, but my gut feeling it lifter, valve train related? Yes the motors had all brand new lifters, cams, springs, valves, and keepers. Is there any adjustment in these that could be causing the problem? Does anyone have any ideas or thoughts on this situation. Thanks in advance!!!

Make sure it is not just the exhaust flappers rattling, frakin' ya out.

Could be several things. However, IF you have a flat tappet cam, there is a chance you lost a cam lobe, since the motor is new, and thats usually when a cam goes flat. I would pop the valve covers off, and take a look at the rockers, springs, etc. Check for loose rockers. A little side to side play is normal, but not excessive and no up/down play.

It could be something like a broken rocker arm nut too. I have seen poly locks crack and fail.

Ticking is usually valve train. Dull thud sounding knocking is usually bottom end.

Ya, that too! The ones i heard usually sound like a knocking/thumping kinda rattle. Jamming a broomstick handle up the tailpipe to hold them open while testing works.

also a exhaust manifold gasket leak will make about the same sound,,,, check the bolts

Check the pulleys to make sure they are tight. My brand new motor sounded like it broke a valve spring or rocker arm stud. Checked it out and the crank pulley had come loose. Jeff Wurl

Thanks so far guys I am going to look into the above items and see what we can come up with. Another question, the other motor has a faint marbley noise coming from under the valve covers. Do roller rockers make any noise?

yup,,,,rollers are noisy

Okay got the valve covers pulled, and it seems to me that all the rockers are loose, with a couple being very loose. I can pick up on the roller end, and probably have a 16th of an inch between roller and top of valve. The are crane roller rockers 1.7 lift. Could this be giving be both the marbley noise, and the tick/light knock? Also how do I go about adjusting these properly?

Bring the number one cylinder to TDC. Loosen the rocker arm stud on both valves and then tighten one up while slowly turning the pushrod with your fingertips. When the pushrod can't be turned then stop and adjust the nut down 1/2 to 3/4 turn more. Then do the other one on number one cylinder. Here's the sequence...you can adjust the exhaust valves on cylinders 1,3,4, and 8. Then you can adjust the intake valves on 1,2,5, and 7. All done the same way by turning the pushrod...etc etc. Rotate the engine one full turn or 180 degrees coming back to the zero timing mark. Now number 6 cylinder is up in firing position. Adjusting the rest of the valves in this order....exhaust on 2,5,6, and 7...then the intake on 3,4,6,and 8.