hi , got a 2008 road glide and the engine has 28,000 miles , once the engine gets hot and the oil pressure drops down to about 15psi at idle ,a metalic rattle starts in the cam cavity , i disassembled it and the chain tensioners are in good shape , so i replaced the oil pump and plate with a screaming eagle unit and i replaced the tensioners as well, and new harley lifters i also replaced the cams with andrews tork cams and the inner bearings , well after the engine gets hot and oil pressure drops down to 20psi at idle , the metallic sound starts , and when it starts making noise its like turning a switch on and the it wont go away unless if i rev the engine to get the oil pressure up to around 30psi .,i am at a stand point , and i need help , any suggestions ? thanks robert

 

That's a tough one considering everything that has been replaced with new. The HD lifters were a bad choice but that's not the source of the rattle. Everything but the chain has been replaced so maybe take a look at the chain? Both are roller chains; are all the rollers working? Could one of the chains have been stretched to the point that at operating temp one gets loose and caused the rattle? I am spitballling now but since the chain is the only thing that was not replaced, kind of points to the chain(s).
Also considering all the parts that were replaced, are you certain the noise is coming from the cam chest? Noises can be tricky.

 

You could try heavier oil as a test to see if noise lessens which could point you to the rocker area

 

once i got the engine hot i could hear the noise with my stethoscope and it is most pronounced on the cam cover and on the top of the cam chest,

 

how are you checking oil pressure

 

i am just going by the oil pressure gauge on the dash and not by the red oil light , once the engine gets hot the oil pressure stays around 20psi at idle

 

i would put a mechanical gauge on it just to verify the pressure. sounds like you are having the same issue even after replacing the items in the cam chest.

 

The clue here is not necessary the bump in oil pressure but rpm that is stopping it. Not a lot of miles on it but can't tell from here how it has been driven.


Get you a Harbour Freight two ear stethoscope. About $8.00. Probe it everywhere. Especially at base of cylinders.

Could be piston slap. Bumping the rpm as long as it's not to bad makes it go away. You can hear .0025 wear at idle.

Doesnt hurt anything at the wear level. When the piston hits the bottom of the stroke and starts up, the angle of the connective rod changes and rocks piston to other skirt.

Sounds just like a bad lifter peck.

If it's that, and your using synthetic oil, try the 20W-50 conventional oil.

 

i did initially check the noise with my stethoscope and i cant hear anything on either side of the cylinders or on the rocker boxes or push rod covers , the noise is very pronounced on the cam cover and some on top of the cavity chest, if i am correct ,if it is a piston noise it would make a noise cold and not hot as the piston expands when hot . the engine starts making noise when hot and it doesnt gradually start making noise , it acually starts like turning a switch on , and then it wont go away unless if i rev the engine

 

did you change pushrods? I would investigate there