BAD-HABIT

My NEW SBC has a Comp Cams roller cam. I am running new O.E.M. Chevrolet roller lifters. I have noticeable lifter noise (tapping). Motor has less than 2 hours on it. My engine builder says this is normal for a roller... I have never had a roller but have never heard that a roller makes noise like a solid lifter cam does....Is he nuts or am I mistaken.... Kinda hard to push the issue with a strong headed builder when he has your warranty (6 mo. parts) and you don't know if he is correct or not.....Thoughts anyone???

"Bad-Habit"

Ted G

iTrader: (1)

Roller cams do NOT make noise like a solid tappet cam. In fact they are usually quieter. Something is wrong.

BAD-HABIT

And in your opinion that "something" might be what? My first thought was the rockers were loose......

"Bad-Habit" ....In a BAD mood to boot!

Thanks

Vinny P

I agree. That motor should be silent.

Vinny P

Thats is where I would look first. Try to adjust the rockers, it may be just that simple. But, take a look at the amount of stud threads that is sticking out of the top of the adjuster nuts after you did the adjustments. They should all be sticking out about the same. If 1 is much higher than the others, you could have a problem with that valve, lifter, push rod, etc. Also make sure that oil is coming up to all the rockers through the push rods.

Ted G

iTrader: (1)

I agree, check all the rockers for adjustment and even height. Look for any that aren't pushing oil. I don't want to scare you but the last roller motor I saw making noise had twisted a lifter and trashed the cam and the lifter bore.

BAD-HABIT

Let's say I check the rockers and they are o.k. and are pushing oil then what? And if any were not pushing oil what would that do to the lifters? The motor seemed to tick alot for the first 5 minutes or so but oil pressure was good (On the gauge at least) and the ticking slowly went away. After 45 minutes or so I decided on a easy run at 75 percent throttle to about 75 percent of my Max R.P.M's this put me at about 4000 and I was there for about 30 or so seconds when I felt the motor bog just a tad and before I could even look at my gauges I heard a Tapping return just as before but VERY LOUD.... A quick look at my oil pressure showed 60 pounds before I shut it off. All this took maybe 10 seconds. I started it up again and nursed it back to the dock. Well today I started it up again and still the noise. I checked the oil and it was clear. But the rockers were pretty dry hardly any oil flowing at all. I changed the filter and the oil flowed great. The tapping went ALMOST all away and the engine "felt" like before the noise started. It was running great. RPM's don't increase or decrease the loudness of the noise. BUT my oil pressure went up 15 pounds at idle to 80 pounds!!!! Due to outher concerns (weather and carb issues) I couldn't get a nice run in today. I really don't want to pull the intake off. Im hoping to re load the pushrods and rockers and get a run in before I go tearing into this....Am I going to damage any thing by trying this?

"Bad-Habit"

Ted G

iTrader: (1)

If the noise stays away and the oil pressure stays up you should be o.k. But watch the oil pressure real close-the lifter noise may be a symptom of a bigger problem. Recently it seems a lot of people are having oil filters shutting down due to moisture content in the oil and you may have had that happen. Since the oil to the lifters is restricted that is the first place a loss of oil pressure or volume will show up.

Vinny P

I would definetly cut the filter open to look for anything that may be trapped in the paper. This is an excellant way of checking for any internal engine parts that are failing. 80 p.s.i. sounds kinda high to me. Are you sure that the builder used a high volume and not a high pressure pump? Also ask your builder if he used any type of oil restrictors in the block.

CheckmateF1

You said the noise went away after you changed the oil filter. What filter are you using? I would try a "racing" type oil filter that has less resriction to flow. Like a Fram HP-4 or WIX racing.

Eric