Question : Ticking/tapping

[NFSINSANE]

I can hear moderate ticking, almost tapping but i suppose there's barely a line there. I just replaced the lifters yesterday, changed the oil. It sounds different, I know most of the lifters were bad, but now it just seems less intense. It runs and starts amazing. It does not stop but it only does it at idle and it's most pronounced at the rear of the motor. I was thinking maybe header leak but I'm open too suggestions. I just rebuilt this motor from the ground up so I'm gonna be rip shit if it's valve guides or something...

[60dgrzbelow0]

Sounds like this can indicate oil starvation in a re-built, partial re-build or even a brand new engine...

Did you "Pre-Oil" the engine before starting it up with something like this?

http://s557.photobucket.com/albums/ss19/60dgrzbelow0/ANEWV6OILPUMPRIMINGTOOL/

Did you use any "Engine Oil Supplement" additive to your crankcase prior to start up? Did you use any Molybdenum Di-Sulphide Grease or special part lube when assembling your engine? Did you run the engine at 1,500 to 2,000 RPMS for about 20-25 minutes when you first started your re-built engine to "work harden" the lobes of the new camshaft and properly break in the lobes and lifters? If so...did you change your oil and oil filter immediately afterward because the Moly-D will clog the Oil Filter within the first half-hour of start-up? If your answers are "No..." anywhere along this line of questioning, then do this:

*Drain your oil and change your oil filter before you start the engine again.
*Get your hands on some GM "Engine Oil Supplement" and put that in the engine, too.
*Get a plastic bucket and use a pair of tin snips to cut off the end of your Oil Filter and look inside for evidence of any metal. Flush it all out with light kerosene.
*Use a Neodymium Magnet to detect any ferrous metal...and anything else you find that is shiny and metallic is either Babbitt bearing material or...aluminum from some other source.
* Run the engine for only 250-500 Miles ...and then change your Oil and Oil Filter AGAIN.

Don't be tempted to use Cheap Oil and Cheap Oil Filters...Use a High Quality Engine Break In Oil...like Royal Purple...Or Valvoline Racing Oil...DON"T USE A SYNTHETIC OIL...The Idea here is to have the parts break in and get comfortable enough to seal your rings and improve compression... Synthetics can be used AFTER 1,500 Miles of Break In Time. Stop using the Valvoline Racing Oil after that...or the special Zinc and other additives will completely coat and defeat your O2 Sensors and the Platinum Screen in your Catalytic Converter.

[NFSINSANE]

I used an engine assembly lube on everything. I did what the haynes manual told me to do to prime it being disable the ignition and fuel pump and crank the engine until oil pressure registers. I did run it at 2000 until it was at normal operating temp. I didn't change the oil right after that though. All the cam lobes look normal, the cam was not replaced upon the rebuild it was in good shape. If worst come to worst I will rip the heads off and see if it is serious.

I just ripped off the top end and checked all I could without removing the heads. Intake valves aren't bent. Should the lifter seats move up and down freely btw, I ask because most of them did but a few were stiff so I took them out and dissembled and cleaned them they now do move freely. Unfortunately I can't start and test any of what I did because I found my lower intake manifold was cracked on the 3 and badly on the 2 ports when I was putting it back together. That explains a lean bank 1 code. I appreciate the help. I'll do what I can to fix MY mistake.

[60dgrzbelow0]

If you wisely insist on doing the dis-assembly, inspection and re-assembly... then you afford yourself the chance of getting a closer look at those lifters... mindful of making certain they go back in the same holes they came out off... for there is always the chance that by not actually "Pre-Oiling" the engine... the engine is naked to instantaneous metal to metal friction...heat... and sadly...very rapid wear.

The Haynes Manual recommendation bypasses the reality that the whole point of "Pre-Oiling" is to fill the oil galleries to the brim and create a fluid environment that is pressurized to an optimal 65 PSI BEFORE the engine can make any substantial internal motions that allow one piece of metal to make contact with another...and heat up ...and create wear. Turning the motor over while waiting for the Oil Pressure to rise to a level sufficiently high enough to defeat all this friction leaves room for doubt about whether or not this process leads to any kind of damage.

As for the re-installation of Hydraulic Flat Tappets... The best method for ensuring that they are not 'air bound' for even a moment ...is to submerge them in a can or container of fresh, Engine Break-In Oil ...like Royal Purple...and using a Push Rod, work the inner hydraulic plungers by hand until the air is purged and they sort of "plump" up. Then...after wiping them off...apply some more substantial Engine Assembly Lubricant like Melling Engine Assembly Lube to all contact surfaces before slipping them into the engine block and allowing them to come to gently rest on the lobes of the camshaft. All of this activity is designed to absolutely eliminate any chance whatsoever of having any "dry" metal to metal contact during those important first few minutes when starting up and running the motor with new...un-lubricated parts.

If you changed the engine oil after your first foray at 2,000 RPM and did not change the oil filter as well... you run the risk of losing a lot of oil pressure or causing the oil by-pass valve to invoke because the heavy viscosity of Engine Assembly Lube that contains Molybdenum Di-Sulfide will clog the paper fibers enough to create a blockage of passing oil. So if it remains to be done... Please change the Oil Filter as well when you change the Oil after you tear things down to square things away...and well before you start the engine again. Before you screw the Oil Filter into the Engine Block ... fill it to the brim with fresh oil...and wait.... the paper filter material will absorb the oil slowly and allow you to add more oil...this takes about two minutes of well spent time to complete and will eliminate any 'dead air spots' when the Oil Pump starts pumping fresh oil through the motor.