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Inconsistent strange noises from upper engine

1204 Views 9 Replies 4 Participants Last post by  rgerdes
Hello 5.0 engine experts. I have a clicking, clattering, ticking noise that I can hear thru my Systemax intake manifold but it does not make noise consistently. Let me start from the beginning to know the whole story on this vehicle I purchased a few months back.

I purchased a 1990 5.0 Mustang LX with EFI and is the roller cam motor. The engine has a Holley Systemax intake and Holley aluminum headswith 2.02 valves, aluminum roller rockers with studs and guide plates. It also has a hydralic roller Lunati cam with a .512 lift and 224 duration. The engine had a clattering noise. Upon checking the rocker arms I found 2-3 that were worn and had to much clearance in the trunion. I installed 1.6 Comp cam stainless steel roller rockers. Started the engine and still had some clicking and had a couple of loose rockers so I thought the lifter were bleeding down and replaced the roller lifters with Ford Motorsports replacements. This motor has the stock Ford spider legged rev bracket with the u shapped lifter holders. I started the engine and still had some clattering and clicking so I torn it down again and rechecked the old aluminum rockers to the new Comp's. I could see that the position off the roller was not correctly positioned on the tip of the valve and opted for new correct length pushrods. Installed them and still had the same sounds. Upon tear down this time i noticed that some of the push rods were out of the lifter cups and after looking closer noticed the top edge of the roller lifter had broken off 15 of the16 lifters. Now very frustrated called Comp cams and spokto a rep whom advised I check to see if the guide plate slot was deep enough. Finnaly determined to deepen the slot and that gave me the correct geometry.
Now I have pieces of the lifter in my engine so I decided to tear it down and rebuild while its apart. Opted for a 331 stroker with all forged steel and Mahle pistons. Had machine shop assemble the short block and recon the aluminum heads. Assembled motor with a new set of FOMOCO roller lifters and the existing cam and rocker arms. Adjusted the valves by turning the lock nut to zero lash and then 1/2 turn more and everything looked fine. Cranked the motor over a few times and all is well on the adjustment. Re-installed the motor and fired it up. Sounded good and then I installed the cat back exhaust. Well guess what the clicking clattering noise is back. Noise occurs every couple of seconds and does not have consistent sound
I and my mechanic friend are baffled. Anyone experience a problem like that. Do I need to invest in some of the rollerlifters with the link that attaches the pair of lifters together and eliminate the factory rev kit? Any help would be appreciated. Frustrated in Phoenix.........
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Are you still running the stock valve covers? Its quits possible the noise your hearing is the rockers hitting the bottom of the valve covers or at the very least, the rocker on the oil fill side hitting the oil baffle. Try cranking it up and lightly touch a long screwdriver onto the baffle in the filler tube, you should beable to feel the rocker hitting the baffle if thats whats happening. Or, just ake off the valve covers and look for scuffs on your rockers and under the covers.
welcome to the site,enjoy!!!!
128 Chris

The valve covers have all the protruding areas ground down. Thanks for the tip
The noise... you say clattering... is it dull, loud, more of a rattle, sharp ring to it?

It's like a tap-tap then a second later a ping and then a second or two later another tap-tap and ping and then a click. It's just not constistant like with a bad rocker.

thanks for replying
no way its as simple as a header leak, bad gasket, cracked header either eh?

If only I could be so lucky. New headers and new gaskets. My ear to the screw driver test indicates mostly driver side. Guess I better pull down the intake and take off the valve covers and inspect.

thanks again
Man oh man, im running out of guesses. When my rockers where hitting my oil baffle, the noise radiated through the whole upper intake so it was a simple, but troublesome time figuring it out. Only thing else i could think of would be detonation. But even if its that, theres so many things that could cause it. If you had nitrious or a blower, inadequate fuel can cause detonation as well as too much timing. Too hot of a plug and not high enough octane gas or bad gas also can cause detonation. And opposite, bad gas with too much timing. Keep us informed on what you find when you break it down, im interested on what it could be.
Help...more suggestions

Has anyone experienced the factory rev kit not retaining the lifters and retainers in place? It almost sounds like occasionaly one will stick and then snap back in place. Do I need to go to an aftermarket lifter with the link arm attaching?

Going to tear down this week end.
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