djhoth

Less than 400 miles on an entirely rebuilt 72 olds 350. Things have been great so far but the engine developed a knocking noise the other day. Thought it would have been a rocker, Iam using comp roller rockers. I pulled covers with engine off and tightened rockers. Didnt really feel any that were very loose at all. Started engine back up and of course the noise was still there. So my question is. Is there a better way to check rockers? And if I did have to remove the oil pan to inspect the bottom end can this be done without removing engine?

cutlassefi

How's the oil pressure?
Pull 1 plug wire off at a time, if the noise stops or gets noticeably quieter then it's in the rotating assembly/bearing, otherwise it's probably somewhere else.

coppercutlass

check the oil., drain the oil filter into a very clean can or even soup bowl inspect it . the bad part is its a new motor., new motors still shed material for alittle while after break in time could be wrist pin or rod if it goes away after some time it could be wrist pin if it doesn't possibly rod you wont know untill you take it apart also try to thicken up the oil with an additive if it goes away it could be bearing tolerances

djhoth

Thanks for the tips guys, Iam going to take a look this weekend. To answer the question in regards to oil pressure. Pressure has been consistent, about 30lbs idling and going as high as 60 at higher rpms.

nofiveo

Take a listen to the fuel pump... I've heard a few that "knock" when runing. A cracked flexplate will also make you think you got a rod dangling

dster69442

Pull your valve cover off and see if the rocker arm bolts have loosened. This happened to me on my new rebuilt 455 this year. I re-tightened using blue locktite on the rocker arm bolt threads. Knocking went away,and 6 months,2,000 miles later, still no knocking. Good Luck

djhoth

I went through the entire valve lash process over the weekend. That fixed it! #7's exhaust rocker was loose. Now I need to wrap my headers, they are so close to my starter. After running a while than trying to restart, the starter acts. Usually within 5-7 mins it will restart. I guess I know what am doing next weekend now!

defiant1

Just for my personal reference: Once you had the valve lash figured, how many turns did you tighten the rockers? Do you have polylocks?

d1

djhoth

I followed my haynes manual, not sure if that was the best idea but it said to tighten 1 full turn after you feel drag on the pushrod. I have the locknuts that came with my comp magnum rollers kit.

panos

I had a knocking noise on my fresh built engine also after about 500 miles,had good oilpressure but it show up that there were 2 rod bearings gone bad so try to see if anything is on the oilpan! mine sounded like that

http://www.youtube.com/watch?v=NdSc1WIXFUc

defiant1

I turned mine a 1/2 turn, then I turned both the polylock and set screw another 1/8 of a turn to prevent them from loosening.

My valve train is a little noisy, that is why I ask. I might readjust again in the future.

Thanks
d1