MyFirst90coupe

Ok, 1990 L98 had the heads off new seals, LT4 springs and access. Stock cam, put in new hardened p-rods at stock length, Crane ultra gold 1.6 RR's. Did the preload by the TDC adjust this intake valve and that exhaust, rotate 360 adjust remaining valves. Did them to 1/2 past zero. Horrible clatter from valvetrain. Popped the VC's and added 1/4 turn. Still sounded terrible. I'm doing the EIOE method ( I think that's what it's called) where you watch the rockers and adjust exhaust when intake is almost closed and so on.
I am on the odd numbered side (it's easier to get VC off) Got to #5 and when I set the exhaust I noticed that the polylock was still really loose. I can push the p-rod end of the rocker down with my thumb almost 1/8". On the others that I have set they do not budge. I'm thinking that's a bad thing and probably the cause of my noise.
Am I looking at taking the intake off again and doing lifters? I do not really want to change the cam right now...well, I can't afford to change it so if I have to change lifters can I put the LS7's in there with the old cam without issue?

Thanks in advance for reading my long winded post.

Jeff

C4Betts

Do you have a roller cam? I believe it is OK to swap out roller lifters on roller cams as they are steel and do not take a 'set' through break in as the flat tappet cams/lifters do.

You should be fine swapping out roller lifters if you indeed have a roller cam setup.

A bad lifter however IMO shouldn't cause a polley lock to come loose. And by polley lock you are talking about running down the main rocker stud nut to the desired lash then running down the inside set screw to lock it on the rocker stud, correct?

MyFirst90coupe

Here's a quick vid of what's going on.

http://youtu.be/X8YRI8BGYn0

The polylock isn't coming loose. The valve is chattering like crazy.

oldalaskaman

shouldnt those rr's be using longer pushrods? the other thing you could try , is with the engine running (messy), back them off till they clatter , then tighten them 1/2 turn after they stop clattering.

cv67

You dont need new lifters at this point sounds like the adjustment is off. Never had luck doing it like you are maybe others have..
Do the rockers one at a time, takes longer but foolproof.

Get it on the heel of the cam make sure theres no up/down slop on pushrod and add your half turn.

87 vette 81 big girl

Go back a reset all 16 valves on your vette.

I don't like setting valves like you did.
Just like Ron don't either.

Set one cylinder at a time.........Intake and exhaust.

Then move onto the next cylinder.

Using a starter bump switch, I can set all 16 valves on a hydraulic lifter cam SBC V8 in 5 minutes or so with the valve covers off.

A solid flat tappet solid or solid roller takes me about 10 minutes to set all 16 valves with a feeler(s) gauge using a starter bump switch.

Make sure the cam is on the base circle or opposite of the cam lobe nose when setting each valve.

BR

oldalaskaman

really sorry for suggesting this, but did you do your adjustment 180 degrees off? and I also agree with the perv. poster

MyFirst90coupe

Here's how I did that side last night.

Here are step by step instructions:

Remove the valve cover.
Identify the number one cylinder.Turn the engine over until you see the number one cylinder exhaust valve rocker arm JUST START to move from the closed position to open. You may need to turn the motor over a couple of times to reach this point, but do not turn any further.
Locate the intake valve.
Loosen the rocker arm adjustment nut until you feel some obvious lash or clearance in the adjustment.
Using the thumb and index finger of one hand, grasp the intake push rod below the rocker arm, and rotate it back and forth (clock-wise and counter clock-wise successively to be sure there is no remaining pressure on the push rod from the rocker arm as you loosen the rocker arm adjusting nut.
Using the other hand, while continuously performing step 6, with a 5/8 socket and ratchet, tighten the rocker arm adjustment nut slowly until you feel a resistance of motion on the push rod.
This will be the zero lash adjustment point. For hydraulic lifters, tighten the rocker arm adjustment nut 3/4 of a turn. For solid lifters, back off the rocker arm adjustment nut until your feeler gauge just fits under the contact point between the valve stem and the rocker arm. Fine tune the adjustment by checking it with a feeler gauge just slightly thicker than the preferred clearance to be sure the clearance is not greater than it should be. If the larger feeler gauge will fit, it needs to be re-adjusted. A lash tolerance of 1-2 thousandths of an inch in the valve adjustment for solid lifters would be acceptable since it may be difficult for someone who is in-experienced to be more precise than that.
Turn the engine over until the intake valve opens and then is almost closed.
On the exhaust valve, repeat steps 5 through 8 for the exhaust valve adjustment.
Repeat this procedure for each cylinder. Be sure to do each cylinder sequentially, either following the firing order, following the cylinders numerically, or in the case of a V8 doing one side of the engine at a time. I prefer to do one side of the engine at a time

mseven

Scorpion posted those exact directions some time back..Comp also has similar directions.
If zero lash and pre-load is a given, all you need to remember is:
spin motor in operating direction (make it easy on yourself by removing spark plugs)
when the exhaust valve starts to open, adjust the intake
when the intake valve opens and starts to close (LESS THAN HALF WAY, too far and you're into the overlap cycle) adjust exhaust...
go to next cylinder.

C4Betts

Looking at the video, it appears that you are able to push the hydraulic piston inside the lifter down and the spring inside the lifter bore under the hydraulic piston is pushing it back up. So there is no lash when at rest but you are able to push it down with some pressure by hand - basically you are operating the motion range of the piston inside the lifter.

This is very typical of new lifters for example that have not been run or gone through any oil pressure 'pump up' cycles.

If these are new lifters it may still be needing to pump up (although you've indicated starting the engine so...) or could indeed be a bad lifter (something wrong with its internal valving that is not holding pressure under load). Maybe some 'dirt' got in there that is preventing oil pressure to that lifter?, etc.

MyFirst90coupe

That is exactly what seems to be happening. I had the car running approximately 30 minutes before doing the preload while I attempted to do the adjustment while running (didn't like that method). These are the stock lifters w/ 130K on them.

MyFirst90coupe

That might be part of the key right there. No where did anyone say that. Most of them say to look for the intake valve to be almost closed. Even still, should there be that much slack in the lifter?

j-wireman

Wow. I have been thinking of changing mine to 1.6 Roller Rockers. Much more to this than I thought. But, I should still be able to learn something here. Thank you, gentlemen.

MyFirst90coupe

Don't be scared young Jedi. I had a tick that I assumed was related to the PO crossthreading #8 plug so I took the heads off and had them gone through. The Rollers were a "while I'm in there deal" If you go with the more expensive Self-Aligning then you really don't have to go through all that much i.e., pushrods and guide plates since you can reuse the stock items. It now seems glaringly obvious to me that this lifter was my tic. I even debated about changing them while the heads were off (regret that decision now). The tic seems to be intensified by the roller rockers and the aftermarket valve covers.

eaglevision993

I also did it the Scorpion-way, as I have their rockers and it was in their manual.
Worked for me on the first try. It takes some time but is worth the extra time. If you have to do it again you will loose that saved time anyway....

mseven

well I tend to believe comp a little more than most "authorities" and this can also be witnessed when a motor is apart a you put a degree wheel on it.
Comp discusses looking at the pushrod...but really becomes the same thing as I described earlier. (read specifically regarding overlap cycle)

Comp Cams Valve Adjustment Linky:
http://www.cpgnation.com/forum/comp-...ment-2076.html
it sounds as though the lifter is bleeding down too fast. If you have good lifters (stock ones are kind of mushy) and they have been pumped up/running already, at first it should be rather stiff to have the push rod sink the plunger that quickly.

MyFirst90coupe

I fired it up last night with the VC off. The lifter did not pump up. Going to pick up a new set today.

Thanks for the link Mick!

Midnight 85

I didn't see this mentioned anywhere above so if it was I apologize. Using 87 vette 81 big girl's method, try moving the pushrod up & down instead of spinning it. IMO this is a much more accurate way to do the job. Try this with the new lifters, I always put new lifters in a can of clean oil for a couple hours, then work the plunger up & down while holding them under the oil.

87 vette 81 big girl

Hi Jeff,

You have some of the basic SBC and similar V8 engine overhead valve setting techniques down but have some errors present too from what I read tonight.
Had more time to read through your entire thread tonight.
Spotted the errors you made.

It is best to start with an engine warmed up to at least 140 degrees block/ water temp when final setting valves.
Allows for normal thermal expansion between the engine block and cylinder head and entire valvetrain components in place or in use.

1) When the exhaust valve just starts to open, set the intake valve lifter preload or flat tappet/ solid roller lifter valve lash setting.

2) When the intake valve opens fully continue crankshaft rotation till the intake valve closes 1/2 to 2/3 closed.
Stop before the intake closes... 1/2 to 2/3 closing point is ideal.
Now set your exhaust valve hydraulic lifter preload or flat tappet/solid roller cam valve lash setting.

If you follow these Two steps you will always be on the base circle of camshaft, opposite 180 degrees of the camshaft lobe nose.

3) You have to make sure you are turning your SBC Vette engine in the correct normal engine rotation direction when setting the valves.
From the harmonic balancer or front of the car, turn the crankshaft clockwise rotation when placing intake or exhaust valves where needed.

4) Used hydraulic lifters with 100,000 + miles of use seldom set correctly with 1/8, 1/4, or 1/2 turn lifter preload.
The internal parts of the hydraulic lifter assembly have excessive wear present and sort of take a set where they will take up valve lash automatically.
On used hydraulic lifters that are flat tappet style or hydraulic roller,
I set the lifter preload 3/4 of a turn down from where the pushrod quits spinning easily with my thumb and index finger.

You do not have a race engine that will spin up to 7,000RPM's or 8K RPM's.
Do not worry about obtaining another 100 RPM's peak operating range on the street with a high mileage TPI L98 engine turning the lifter preload only 1/8 turn down or so.
Be lucky if you ever see 5,500RPM's stock driving down the road before the engine runs out air with very long intake runners present and very mild camshaft GM supplied.

5) You are setting the Poly Locks wrong, why some are coming loose on you.
You turn the Poly lock and center allen set screw together to lock the poly lock down.
If you turn or tighten the center allen set screw by itself holding the poly lock body with a wrench, it will come loose from a running engine's valvetrain in motion.

Turning the poly lock and allen set screw together.........locks or forces the poly lock to bite much harder on top of the rocker arm stud and against the upper threads of the studs & internal poly lock female threads.

I use a starter bump switch to set valves always.
I can turn the engine over in 1/16 turns at a time or less degree increments if I desire that way.

Makes the task much easier and saves me at least 1/2 hour time vs. using a socket and breaker bar on the 5/8" inch balancer bolt.
Saves my knuckles and skin on my arms too.

If on an engine stand set valves rotating the engine over manually.
That is no big deal,
It is easy to turn the engine over by with a 1/2 inch drive Snap On ratchet and matching socket needed.

Be sure to remove all 8 spark plugs in your Vette before setting valves.
You will not be fighting against engine compression.
You will remember this tip if you ever set valves on a race V8 engine with 17:1 or 18:1 static compression ratio.

Brian

MyFirst90coupe

Brian,
Thank you for taking the time to write that up. I will use yor very clear and concise instructions tomorrow when I put the new lifters in.

As a side note. I did not have a problem with the polylocks coming loose. I'm not sure where that came from. I did as everyone suggested. I did the 3/4 turn then back 1.8 of a turn tightened the set screw then turn the nut 1/8 turn more