Thread: Valve Train Noise

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Ok, so after building hundreds of turbine engines for aircraft, I thought I give a rebuild to 350 sitting in a 57 chevy pu a shot. All went well, however, I have louder than expected valve train noise, especially from #1 exhaust where I put a stethoscope on the head and can very obviously hear a distinct tick at that location and not so much in others. First thought is bad lifter. I have read that a hydraulic roller setup is more noisy than a hydraulic flat with higher profiles on the roller setup. Did do the 1/2 turn after 0 lash and also tried to adjust running, with a notched out old valve cover of course. No joy on changing the audio on that #1 exhaust. Decided to investigate the #1 exhaust area anyway since why one and not others? Found what I thought were some unusual heat marks on one side of the rocker roller. (Photo's attached). Did not see this discoloration on others except for one other on #7 exhaust which is the second loudest under the stethoscope. Valve geometry appears to be on. Has anyone else have this issue with these indications and noise? Engine is strong and runs great, just the valve noise and heat marks that concern me.

Here is the engine setup:
Chevy 355
AFR-0916 heads w\ 1.209 OD springs at 135#, 65cc
Comp 280HR Cam
Comp 853-16 Retro Lifters
Comp 19002-19 Rockers 1.6
Hypereutectic pistons @ -6cc
Compression Ratio= 9.66:1

I have talked to Comp Cams on the issue and they do not have an answer as of yet. In reviewing this froum, I looks like a lot of smart folks out there so thought I will give it a shot.

looks like your at the bottom of that rocker stud . bottom out ? you try swaping that rocker to another cylinder. sure you not eating up a push rod or cup in rocker . make sure you do not have a header leak. roller rockers can make more noise on any cam grind. make srue your poly locks are not hitting in the roller rocker body

May be an optical illusion, but it looks like your rocker is not setting parallel with your valve train. Notice how the roller is being shoved to one side. The side that is touching the hardest is where the heat mark is. It is not centered on the valve stem either. Might have a bent rocker stud.

it ok to point to be off cc long as your not off the roller tip or stem with bigger runners i use the isk adjustable push rod guldes to move push rods away from intake port and when thats done your track will be off some what.looking at the rocker studs and that head bolt look s like there very close .did you check mid lift for push rods .push rods look to short

Thanks for the replies. Little more info: I have swapped out rockers into another position and still have the noise relative to same valve. Photo is more a optical illusion it that it appears that it angled parallel to the head, however it is at an angle from top view as compared to intake, so if fact, they are not parallel to each other. Is this not correct? Also, find attached photo of witness marking when putting engine together for what appears to be correct pushrod length. Not sure what is meant by mid lift for push rods. Push rods do have clearance between the guide and rod itself. Removed pushrod and found no evidence of contact with guide. Rolled rod and did not appear bent. No signs of damage or other unusual markings on rocker like if it was contacting polylock. Have not tried moving pushrod to another cylinder. Worth a shot?

Comp Cam did indicate that it appears that the valve is not rotating. Did not think they did since I have seen no discussions on this subject. They indicate this because of the heat mark on top of valve as a stationary mark.

Any other checks I can do?

well the valve to valve guide sounds to be to tight ??? if your saying that the lifter is not bad its a hyd roller lifter lifter not hitting the block . the push rods are not bent or tips not burnt up . your rockers are not hitting any where out side or in or inside of valve cover bafflles . you moved that rocker still getting sound off the cylinder ? with deferent rocker . then its a bad valving in that lifter . or sticky valve .or hitting the piston . burnt header gasket sound just like a rocker . mild lift is how i check my push rod geomerty so at 1/2 the lift of the cam you should be on center of valve stem face

Not saying that lifter is not bad. Just want to see if there are any other checks or if there is something else at play before I change out the lifter, not as easy as those ls engines. Would bad lifter cause the discoloration on rocker?

Checked valve to piston clearance at build with the silly puddy trick and it checked ok at build. Also checked with a feather around the exhaust header to see if there are any leaks.

Is there a way to check for sticking valve while installed?

well that part of the roller tip looks like it not in track so its not seeing any wear . the only thing i see as a very corse finsh on the valve stem . lack of oil .the push rod plug with heavy lube or junk . or the pisser plug in the cup of rocker. this is the first to things i look at when building up the upper end of a engine . that and i clean the inside of the push rod newor used with a push rod brush

grab that rocker at O lash see how far you can move it side to side looking at the roller tip and valve stem see how far it can track side to side on the rocker and check to see if it can hit any thing when you move it .i do this and if way off some times you can move the guide plates a bit or go with adjustable .still even running off track still should not make more noise less the body is hitting some where.as for checking for a sticky valve you have to get the valve spring off .there ways to go about this take plug out put air in the cylinder get a spring tool .and set up a test spring move it up and down by hand see if it sticky .for getting the lifter out it is not a big deal a 289 with a roller cam you have to pull the heads to get the longer body lifters out

Why is the roller being pushed to one side? Look at the side to side gap in the 3RD and 4TH pictures. It doesn't look like they built like this (see 1ST picture) or do they just have that much slop under pressure?

Still looks to me like the rocker stud is bent or the stud hole in the head is not straight.

Thanks for the help guys. I will open it up tomorrow and check side movement at 0 lash to see if anything offending. I will check the clearance and movement of the rocker roller. Think when I took the shot I was moving the rocker side to side so it might have ended up against one side of roller.

I was also going to check bleed down of the lifter. I assume if it is at rest in the heel of the cam, the lifter should bleed off. If at mid point I should not be able to turn the polylock without the valve moving downward, hence hydraulic lock. Would that work to determine lifter is bad and bleeding out while running? Has anyone tried this?

Let you know what I find. Thanks again for the suggestions.
Jeff

To test and see if the valve is rotating mark the side of the valve stem above the valve retainer with a sharpie or magic marker. Then run the engine. You should see results straight away.

well your EX has no rotators and on all race stuff we loose them most OEM stuff now the heads on longer use them some bbc had rotators on IN and EX. as for the ex if it should be turning i would say no or lets say not much .i have built hi lbs engine with 270 to350at seat and 700 past 1000. open you see some lines on stem like this + but not shinny like they are spinning alot ,so if the spring was moving alot i wound worry that you have have low lbs on the valve that would be going in valve float were the spring start s to jump then it will dance a round . if you can check your leak down thats hard to say i would say at O lash after it been ran . check another cylinder and check the one that will not take lash it should not be loose it should more like the lifter try some carb cleanner spray it down the push rod and let it set they said that would un stick a hyd lifter old hot rod trick ? hard to say if it will work . there is two other thing s you may have going on with this lifter the valving got hang up start the engine up and work the lifter up and down threw lash go to 3/4 of a turn then to O and do that 3 or 4 times then at O go to a 1/2 see if that helps .if you are run comps there are new hyd rollers lifters that take less then a 1/2 turn there for HI rpms short valving.so they do not have not much valving in them.did some one get it mix up going down the line ? i hear that this lifter may make more noise?? and some one makes a roads leaky roller lifter mixed up valving ? i not sure who makes comp roller lifters many cams companys do not . try less then 1/2 first before cranking it down to 3/4 like i said . all my street rollers i go better then 1/2 turn now.on the hi RPM HYD roller lifters i still set at 1/2 but i do not use any comp stuff .has for the side to side play it can be alot the push rod guides are the only thing that keep the roller tip and valve stem tracking so i grab then and push them side to side with my hand i first back the studs off a less then a turn so i can tap them side to side some guide plates have some slot to them or bigger holes so they can be moved some to get your best tracking on the roller tip and tq the studs down. if that will not work then i go with adjustable ones like i posted . or you can slot yours with a stone on a die grinder .this and mid lift is a very big deal that many over look with the more after market stuff the more you have to check this stuff just cuz its new may not make it bolt on like they tell you or right very few times you will get both i spent days getting shaft rockers and push rods right on race engines with the help of a mill and a lathe

Followup:

Sorry I have not gotten back sooner on my findings. Grabbed some calipers, did some measuring and did find track was slightly off between the two valves on #1. Had enough movement in the guide plate to get track dead center. Did the past 3/4 then back to 0 then 1/2 guidance. Reassembled and still have the tick. Well, can not say we did not try. Going to pull apart to get to lifters and RMA them back to Comp.

More concerning now is when I popped of the cover this time, found another serious heat discoloration in the roller on rocker on intake now on problem area and found distress that is appearing on a couple of others in that bank. Going to RMA those to I suppose

I attached a few photos of the distress of the roller and additional photos of geometry just to make sure it looks OK to everyone.

Jeff

Sorry it took so long to get back but, finally had some time to take another look and adjust per all your recommendations. Did adjust the guide plate and was able to move it dead center over tip. Did the 3/4 to 0 to 1/2 several times. Checked stud for for being bent. Put it all back together and still have the tick on a couple of lifters. Guess it is a RMA back to Comp on those retro roller lifters and rockers since now I am seeing more heat distress on at least 3 rocker tips.

I have attached photos some more geometry to make sure I do not have another issue going on from anyone's point of view. Also, photo of another rocker found with odd heat distress.

Thanks
Jeff