leadfoot4

iTrader: (1)

Checkmate, while I completely understand your method of setting valve lash, I don't necessarily agree with your lash setting. In my '96 Z-28, I'm running GMPP S/A roller rockers, stock length, Manley hardened push rods, and CompCams 875r lifters. This set up has been in the car for the last 8-10,000 miles.

After some initial fiddling with the lash setting, set with the engine running and at full operating temp, I have the pre-load set at 1/8 turn, per the direct recommendation of the two different CompCams people I spoke with. I would think, hopefully, that the Comp tech people should know what's best for their products. In my particular application, "So far, so good"...

moehorsepower

iTrader: (3)

Here is one to check, We had a car on the Dyno and it sounded just like a lifter tick, everyone was checking everything like you and guess what, it was an intake leak, sounds crazy and I did not even believe it, but we pulled the intake right then resealed and the tick was gone!!

Slowmaro95Z28

When you're looking for zero lash are you twisting or moving the pushrods and tightening until you feel drag? If so I made the same mistake. With poly lock style nuts you just hand tighten them until they stop for zero lash then go half turn past that for stock lifters. I had the same sound and it was my fault for not doing it right the first time. I hope this helps.

Fixxer99TA

iTrader: (5)

How did it go ripping out the exhaust and checking for rust/holes/leaks Stealth?

95hawk467

iTrader: (3)

I had the same issue when I put everything together after getting my heads/cam back from Lloyd. I have the samw setup as far as rockers guideplates etc. I went over everything more than I care to count. Finally I sprung for LS7 lifters, put them in check everything out and have been quiet for about a month. The lifters that were in there originally on had about 2000 miles on them, and they were just stock replacement. Not sure if it helps, just thought I would throw it out there.

StealthFormula

iTrader: (35)

Just fired it up and the ticking is still there! I even made sure the 02 sensors were perfectly tight.

I can't really understand what the issue is...The rockers aren't ticking because I know how they sound when they do since I adjusted the valves with the motor running. They are squirting oil like they should so the lifters are working properly it seems. Good thought on the manifold, but I know that thing isn't leaking because I dropped it straight onto a thick bead of RTV and torqued it in sequence. Pretty puzzled still, I may just tear it back down stick new lifters in and go from there. I leave in 2 weeks so it wont be until xmas that this POS gets done! I am so mad right now I have already punched a hole in the wall and broken a drawer within the last week

RickyMartinZ28

iTrader: (5)

well... its pretty

-Rick

leadfoot4

iTrader: (1)

I went back to the original vid and gave it another listen....boy that tappin' is NASTY! Almost sounded way too loud for just loose lifters, more metal to metal....Given that you checked all the really obvious stuff at least 2-3 times, and the lifters SHOULD be OK, since they weren't noisy right up to the time you re-fired the engine for the first time.....

Is there a chance that A) you have a valve spring coil bind issue; B) a mechanical clearence issue, such as the underside of the retainers colliding with the oil seals; or C) your new valve springs are too stiff for the hydraulic lifters, so they're not really pumping up correctly?

Just something to ponder for the next few weeks..... Too bad you have to put this project on the back burner for so long.

StealthFormula

iTrader: (35)

I don't think theres a coil bind issue, my PAC 1518's are a .650" lift and I'm in the .570's with my cam. Lloyd set them all up so I think they should be alright but your third point does seem very possible. Im kinda leaning towards it being the lifters now. I figure I might just tear it down and replace the lifters and see if thats the fix. If not then do some more hunting but the lifters do seem like a possibility. Something that makes sense now....With 1/4" turn preload all the rockers would squirt oil but with say a 1/2" turn or more like recommended for stock lifters, some of the rockers would not squirt oil which may make sense of your third point.

I will probaly grab some LS7's or I may just get the Comp R's assuming Comp has fixed whatever issues they had with them. You seemed to be fine with them so I may give them a shot since they practically have a set place to set preload at.

StealthFormula

iTrader: (35)

That actually helps alot because it just may be my exact issue. What preload did you put on those LS7's?

leadfoot4

iTrader: (1)

Good luck with that idea. Just as a point of reference, I'm using the LT-4 valve springs. I've had them in there a little over three years, but I store my car for the winter, so it doesn't see a lot of miles (or road salt, eiter!).

In fact, that was part of my reasoning for putting new springs in the motor....It sits quite a bit with the valve/springs/lifters in one position for extended periods. I don't know what the long term effects of that are. I do start the car every couple of weeks during the winter to warm it up, and circulate the oil, but still, it sits for a time.

95hawk467

iTrader: (3)

I did my adjustments with the motor running when I put them in, but I believe I set them about an 1/8th of a turn after they stopped clattering. I have been running for about 2 months now and the issue hasn't come back. Before I put them them in, I would adjust them and as soon as I took it out and got on it a little the noise would be there. I hope this helps and good luck.

StealthFormula

iTrader: (35)

Thanks alot leadfoot4 and everyone else for all your help! I guess I got a plan so I'll see how that goes.

BTW 95Hawk467: Where exactly do you live? I live in south eastern PA right below Quakertown but have family up in the Montrose area which I assume is up your way?

leadfoot4

iTrader: (1)

"hawk", just for informational purposes...The point at which the lifters stop "clicking" is called "zero lash". At that point, MOST lifters will require a little "pre-load". That is the 1/8, 1/2, or 1 turn, that people then talk about.

95hawk467

iTrader: (3)

Stealth, I live near wilkes barre in mountaintop. Actually I know exactly where Telford is, I used to live in Kintnersville(right above Ottsville).

transam5.7lt1

iTrader: (18)

Sounds like a loose rocker arm.

leadfoot4

iTrader: (1)

It's a small world.... Some of my ancestors are from Wilkes Barre.

StealthFormula

iTrader: (35)

Ok well I put in the LS7 lifters this past weekend and fired it up yesterday and the noise is still there. The rockers are squirting oil perfectly and the car drives fine.

I talked to Bret Bauer the other day and he said that its simply how loud those particular rockers are and swapping to LT4 valve covers or some billet ones would quiet it down. He reasoning is that the stock LT1 covers were designed for use with stamped steel rockers where as say the LT4's were designed for use with roller rockers and they are known to keep the noise inside. Makes sense to me so that looks like the next resort.

fergymoto

iTrader: (129)

Have you put the car up in the air and put your ear to the oil pan yet?

Fixxer99TA

iTrader: (5)

The LT4s do help quite a bit, but your tick is a little on the loud side. I would be under there like fergymoto listening to the oil pan (but I am sure you have already dont this).

I could be wrong though, some rockers are louder than others.... Be sure to post back with an update when you get those LT4s on there, I'm interested to see how it turns out.