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Discussion Starter · #1 ·
Could someone please recommend a non-additive, conventional SAE 30 oil for breaking in mismatched cams to non-original rocker arms? I recently installed a pair of used OE cams with OE rockers that were also not originals and were out of order. (My engine is a high-port.)
I have looked at Shell's Rotella T1 SAE 30 and Lucas SAE 30 Break-In oil.

There is ticking and clattering (only when the engine is accelerating under load) that I am trying to eliminate.
I did a "break-in" after installing the cams, but I believe I made a mistake in selecting the oil.
I mistakenly used Valvoline 10W-30 Synthetic Blend (thinking it was conventional oil) and added a zinc additive and ran it for 100 miles (front end was elevated).
I was later advised that a "No-additive", straight-weight SAE 30 conventional oil would be better, as synthetic oil actually protects better against friction better than conventional oil and, as a result, would inhibit the metal cams and rocker arms to wear-in together as they need to.
(At this point in my effort, I am thinking the ticking/ clattering on acceleration under load could be due to the uneven wear between cams and rocker arms.)

I am a little confused after reading Shell's description of their Rotella T1 SAE 30 oil: "Shell Rotella® T1 oils use well-proven performance additives to fight engine wear and prevent deposits, providing reliable lubrication and consistent performance."
Would these performance additives inhibit the cams and rockers from wearing-in together? (I plan on running the break-in oil for 500-750 miles.)
Would a designated "Break-in" oil such as Lucas SAE 30 Break-In oil be more appropriate for this?
 

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As long as the parts are in good shape you shouldn't have a problem. The only time I have have had noise when swapping cams or rockers is because I didn't prime the lifters. If your lifters have air in them they can make all sorts of noise. Also if they have air they won't pump up correctly and give correct lift.

Another thing I have to ask. Are all of your shims original? If you have moved any around you may have to go around and clearance check everything.
 

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Discussion Starter · #3 · (Edited)
Hey Y2K.
Yeah, the cams and the rocker arms (not a cam/rocker set that had been worn in together) appeared smooth and in great shape. Those shims are the original ones. I think I knocked one loose, but I put it back in its spot without mixing it up with another one. I made a real effort not to move the shims while I was in there.
 

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Discussion Starter · #4 · (Edited)
As far as the lifters go, I submerged them in oil, and bled the air out of them using a thin allen wrench to depress the check valve inside them. I kept them upright and submerged in oil until I put them in the head. Once they were installed, I then went about installing the rocker arms and cams. I did wait a couple of nights before returning to add the oil, put the valve cover back on and crank it up.
The little galleys that the lifters sit in had some oil in them, and after installing the four on the exhaust side, I "topped off" the four lifter galleys on the intake side before installing those lifters. Maybe waiting the the two nights allowed the oil to run out of a lifter and let air in?? That just doesn't sound right. Otherwise, lifters would be ticking anytime the car sat for two days without starting, given the oil would have run down to the oil pan. Right?
I think I am just going to have to take the VC off and check the lifters for movement and potentially replace one. NortonMechanic suggested doing an engine flush first. The original reason for replacing the cams was excessive wear on cam lobes and notable wear on the rocker arms, ~~> oiler tubes gummed up not lubricating cam/rocker area. I removed the tubes and cleaned them out by taping the little holes closed and filling the tube with carb cleaner, soaking them for a couple nights, and then blowing through the tubes to verify the holes were no longer blocked. So, I trust the tubes are no longer blocked. Norton Mechanic was suggesting the tubes and the oil passageways between the pump and the head could be gunked up.
Are you saying in this engine it isn't necessary to "break-in" the odd cams to the odd rocker arms? The reason I ask is because someone told me this, yet others have told me that the break-in is necessary for the first 100 miles.
When you installed used cams, did you do a "break-in" period, too?

As a side note, The ticking/clattering noise I get only occurs when the accelerating but only when the wheels are actually on the road, propelling the car forward (2-4th gears, up to ~3.3k rpms). Yesterday, I elevated the front end and engaged the transmission, accelerating through all 5 gears, and got ZERO tick/clattering. So, it's like only when the torque actually transferred from the engine to the wheels on the ground does it make the noise. Elevated wheels, no noise.
Check out this thread.
 

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I've swapped cams from other engines, replaced rockers from other engines and even used new parts without any noise problems. The parts are very close tolerance and as long as they have good oil flow they won't wear at all. so they really don't wear in or mate to each other, if they did you would have metal in your oil all the time. The only thing you have to worry about with used parts is if they are in good shape and in stock tolerance.

I wonder if your noise is from something else.

When I put a engine together I measure all the parts to make sure they are within FSM tolerance. If certain things like cams or rocker arms are not in tolerance they probably had bad oiling or contaminates in the oil wearing the surfaces down. A well maintained SR20 engine can last for over 300k miles before wearing stuff out. If you had a worn cam and rockers I would also worry what else is worn in the engine. If it were me I would just pull the motor and do a freshen up on it.
 

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Discussion Starter · #6 · (Edited)
Ok, wow. This is interesting. By "a freshen up" do you mean steam-cleaned at a machine shop? Any idea what it would cost to have the motor pulled for a freshen-up?
Maybe it's like you suggest, and an oil passageway leading to an oiler tube is partially blocked? What is your opinion on using an ENGINE FLUSH product?

When replacing the just the cams/rockers/ lifters, is a shim clearance check always necessary? (potentially for new shims/ rocker arm guides), or is it normal to leave the original shims/ guides in and not need to measure for new shims/guides?

The strange thing is that I did not notice the tick/clatter when the worn cams/rockers and semi-gummed up oiler tubes were in there.
I was really just going in there to replace the timing chain guides and tensioner because there was slack in the chain, and it was slapping the upper guide. I happened to notice the pitting on the cams while I had the VC off and went about switching them out, too.
Several years back, the oil pan was dented up and obstructing the oil pick-up's mouth. The oil pump was cavitating, just not completely starving the engine of oil. The gumming up of the oiler tubes and wear to the cams may have happened during that time. I bent the dent out of the oil pan, and the pump was fine.

Regarding the lifters, if air was in one or there was a bad one, wouldn't a lifter ALWAYS make noise (tick/clatter) whenever the engine was running or being revved and not just when accelerating (wheels on the ground)?

I cleaned out the gum that was blocking up the tiny holes on the oiler tubes, yet it's only now, after doing that, that the ticking/clattering is happening. But it only occurs when accelerating with wheels on the ground up to ~3.3k rpm.
I read about tick/clattering happening due to exhaust leaks at the manifold gasket or at the EGR tube, but I would expect there to be tick/clatter happening WHENEVER exhaust was being created (i.e. revving in neutral). But it's only there when accelerating when the wheels are on the ground.

I also replaced the oil pick-up and put in one from a p11, which requires a flat, embossed gasket instead of the o-ring (p10). I faced the raised, circular ridge towards the oil pump, not downwards toward the oil pan. The gasket gets compressed when the two little bolts to that leg of the pick-up are tightened. Could there be low oil delivery to the lifters due to the direction I installed that embossed gasket?
 
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