OhioTed

We recently built up a 289 with an Eagle-brand 347 stroker kit and Edelbrock Power Package flat-tappet cam/aluminum heads/intake kit. Roller rockers are utilized as well.

Engine runs great, but after a couple of hundred miles the valve train now becomes noisy after the engine is up to temperature.

Went back and check all component specs, including pushrod length. Also checked oil pressure - 35 psi @ 1000 rpm. Have adjusted preload on lifters several times now. Summit, Edelbrock, and local shop's recommendation are vary slightly, but have tried anywhere from 1/4 turn to 1 full turn most recently. Still noisy when hot.

Any suggestions? One shop suggested I'm getting a lot of expansion from the aluminum head and need to go with even more preload, but that does not match any manufacturer's specs. Another shop said the lifters may be bad. Any information would be greatly appreciated, as I am out of ideas.

Gun Jam

Does it do it when it first starts up?
or only when hot?

which brand of lifter are you using?

are all the valves doing it?

After its hot remove a valve cover and find a valve that is in the fully seated position so there is little to no pressure on the push rod. Use your thumb and attempt to push the rod into the lifter by pressing on the top of the rocker arm just above the pushrod. It should feel rock hard if you feel any squish its probably a bad lifter. If you dont feel any squish is there any noticeable up and down movement in the pushrod it too should not move up and down at all

-Gun

67mustang302

Did you break the cam in properly? Flat tappets are pissy with oils these days.

As far as preload, minimum is best, 1/4 turn, but anywhere from 1/4-1 full turn is fine.

A lot of valvetrain noise is from rockers and cam. Which rockers are you using? Chances are the Edelbrock cam is just noisier than some, customs tend to be the quietest.

MonsterBilly

I have a set of scorpion roller rockers on my engine and I have a set of aluminum heads. they are noisy as well. In fact, you can here them at idle when you stand bhind, and beside the car. I also have a loud exhuast. I have just gotten used to it.

dawson1112

yea I have 1.7 rrs on x302 aluminum heads and it sounds like a sewing machine under the valve covers. Some rrs are just noisy

Op if you can get a video of the noise up maybe someone can tell you if its an abnormal sound.

67mustang302

Scorpions are actually some of the quieter rockers out there. Noise is more likely from the cam setting the valve down hard or throwing the rockers around brutally.

Another reason I go with custom cams, the custom grinders for the most part are really big on picking up and setting the valve down gently with the cam profile, and being gentle with the valvetrain; so the valvetrain lasts longer and makes way less noise.

kenash

Hi,
I realize, this is 5 days later but,.......
Have you taken a peek at the wear pattern on the valve tip, if there is one yet? This will give you an indication of your P/R setup.
Good Luck!

OhioTed

Thank you for all the input, gentlemen. Here's the latest. Pulled the valve covers back off last week and started from scratch, at 1/4 turn. Fired it up, noisy as heck. Went back in, applied a full turn, fired it up, sounded great. Let it come up to temperature, still sounding great. Headed down the road and I was riding high - until the engine got good and hot. Then it started getting louder and louder. By the time I was back home we were right back where we started from.

Got on the phone with Edelbrock, because they built the motor (seriously - no kidding - long story). Anyway, they asked for all specs, what oil we're using (conventional, NAPA, 10w30), what break-in lube (CompCam additive). They asked if ends of pushrods are distorted (no). Asked if there is any metal in the bottom of the oil filter. Cut it apart with snips. There is metal there - trace amount of very tiny particles.

I reported all to Edelbrock, but no response yet. Communication with them is intermittent at best. I did not yet check the lifters per Gun Jam's advice. I figure Edelbrock will next have me pull the lifters, at which time we will hopefully be able to evaluate them. Did not closely eyeball the valve tips for wear pattern. Will do so.

That's it for now. Sure is frustrating. Note, reason Edelbrock got involved in rebuilding motor is because first time around the cam tore up all the pushrods. There's something weird going on here . . .

67mustang302

Metal in the filter....tiny metal bits, or is it like a paste or peach fuzz? A little bit of metal is normal, especially on a new engine breaking in, but it should be like peach fuzz or a paste (often collects on the magnet on the drain plug). But it should be a small amount and there should not be any particles that are large enough to see as being a piece of metal.

Did you break the cam in with break in springs, or the springs for operation? Flat tappet cams these days have all sorts of problems because most of the oil these days is ****ty. And with the more aggressive cam profiles these days even when everything is right, flat tappets can still have issues.

OhioTed

The particles are not like the "fuzz" which shows up on magnetic drain plugs, but more like what is created when you file metal (bad).

When the cam and lifters got torn up first time around I asked Edelbrock about the need for break-in springs. They said "no".

Sure wish we would have rebuilt the second time around with a roller cam, but Edelbrock performed the work, so . . .