Hi all

I have a serious valve train noise so decided to run engine without valve covers, all rockers move perfectly but one of them is just shooting a stream of oil as you would pressure it out of a injection needle, all others in a controlled manner release oil from rockers, is this normal behavior from a lifter i suspect that one do not get up pressure.
New valve springs Z06, new comp cam lifters, new camgear Torret bearing, original cam and pushrods, have ruled out exhaust leaks, bad injectors, car runs strong and no misfire also no codes.
I suspect lifters not getting pumped up properly but i have good oil pressure 35-50 psi depending on rpm, also new oil pump Melling Oring is good no problem there, i am just out of ideas.....

 

wow never heard of that. Over 30yrs working on cars. Well the lifters are mechanical so my bet it's a bad lifter but let's see what others said before you start tearing into it.

 

Video?

 

This is strange yesterday nbr 5 intake just sprayed like crazy, now its same as the others but as you hear it sounds horrible.
Both sides have same flow of oil, will try a Wynn hydraulic cleaner additive to see if it gets better otherwise i suppose i will have to remove heads to see whats going.

 

I'll get right down to the point. What lifters are you going to replace them with?

 

I guess i have to remove the heads and check those new comp cams lifters for issues and lifter gallery, what makes me oncerned is that i begun all this by installing a Texas speed low lift cam with the stock lifters and stock pushrods, at start up it sounded like this.
I replaced lifters and measured pushrod length to be correct zero lash and so on, started
it up and still the same sound.
Next step re installed the original cam and took Texas cam out it looked good no special marks but offcourse it had not run more than 10 - 15 minutes, so now in this video i have all stock setup with 7.40 pushrod except OEM Comp cams replacement lifters and blue valvesprings, i have 7.425 pushrods anbit longer that i can put in but i am afraid i may cause more trouble, heard a bit longer push rods would make valve train more quiet.
Before cam change no issues with motor it was perfect, this sound direct after startup with the Texas cam, so very confusing, could be a bad cam bearing but i did not have any issues with changing cam regarding to hurting the bearings also i have good oil pressure.
Next set of lifters if these are bad will be LS7 but something tells me i have some other issue just dont now what i am out of ideas, i have not built LS motors before only several old SBC and BBC so little bit hurt since i feel the LS family is easy to work on also.
Aside from this really bad valve train sound engine runs really strong and no misfire.

 

Didnt see any info about the rockers. Original?

 

Yes completely stock, checked them when installing cams and they all seem to be in good order but i have not done a trunion upgrade, after running engine all rockers tight and lifters pumped up on driver side will check passenger side.
Also have new Dexos 2 oil Castrol synthetic 5-40w in engine, did cut oil filter and not a single metal particle in filter.

 

Cams add noise. Did you change lifter buckets? Are you POSITIVE on your pushrod length? You need to update the rockers trunnions at minimum, no sense in adding all that and not doing the rockers too. The new valve springs could be an issue along with those did you add new valve seals/seats/retainers etc??

 

Yes new buckets, new springs with correct OEM seals did reuse old retainers, sorry to say i discarded the old original springs.
But could blue springs Z06 GM be a problem maybe causing the sound, i have considered this possibility but discarded it as they are GM original parts for LS6.
Trunion upgrade not done could this cause this trouble, on visual and feel inspection they feel good, will do this upgrade.

 

Just throwing out ideas and thoughts. After hearing your video I doubt its the springs unless they are broken. All your rocker arms are currently tight and functional? Just hoping none of the lifters have turned and are eating the cam.

 

Yes that is defenitely a possibility, i am thinking of isolating one cylinder lifter pair in firing order sequence by remove pushrods and let engine run on seven cylinders to see if i can find and isolate the troublesome lifters, is this possible or do i disrupt oilflow to all other lifters also, idiotic idea could probably risk oil pressure in motor.
Yes all lifters pumped up and all rockers moving ok as far as i can see and hear, it fels more like sound is coming from lifter cam region also i can ” feel ” a slight tap when holding hand on intake.

 

There was a year (98-99?) when the OEM rockers had the needle rollers failing. The rockers would "rotate" on the trunion due to several lost needles that hopefully made it down to the oil pan.

 

Just a thought and it's an old school engine builder trick my old man used to use a bunch when diagnosing valve train stuff, but if you get a mechanics stethoscope from harbor freight or Amazon you can put it right where the head and intake manifold meet above each cylinder and maybe pinpoint where the sound is or isn't coming from.

​​​​​​Another thought is maybe the stock pushrods are too short and you need a 7.4-ish to make the new litters happy. It would definitely be worth taking the 15 minutes to measure to eliminate that as a possibility.
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I have a 02 M6, have changed oil and could not find any metal parts but yes the rockers are also in there but i have checked each one of them and they seem to be in order, will do a trunion upgrade this winter.

 

Yes i have used such a device and it just seemed to be even sound all around but bad noice in the top end of machine, yes i will drop in 7.425 pushrods have a set from BTR, will keep you all posted about outcome.