87 2.8.I need to check the lash before the valve covers go back on. Here is what ive done. Tightened the rocker nut until there is no up and down play while the lifters were at TDC. I then slowly tightened the rocker nut until the pushrod got hard to spin. I did that to all of them. Do i need to check the space between the top of the valve and rocker with a feeler gauge? If so whats the specs???

The point where the pushrod no longer wiggles up and down (i.e. is snug) is zero lash. From there, you turn the nut another 1.5 turns. And you're done.

If you're going to use the "spinning the pushrod" method, then you would tighten until you *just* start to feel a little drag as you spin the pushrod. Then tighten another 1.5 turns.

No feeler gauge necessary.

quote Originally posted by 87antuzzi: Tightened the rocker nut until there is no up and down play while the lifters were at TDC.

That part is correct. Zero lash is the very first moment that you cannot move the pushrod up and down between the lifter and pushrod as you are tightening down.

quote I then slowly tightened the rocker nut until the pushrod got hard to spin.

Incorrect. Tighten 1.5 turns after zero lash. Depending on your grip, you could have bottomed out all the lifters, please double check.

Edit,,,, I found my post explaining valve lash here,,,,

https://www.fiero.nl/forum/A...21-2-095970.html#p18

[This message has been edited by jetman (edited 05-07-2010).]

The way they are now is too tight.
Back them off to zero lash and follow directions.

The 1.5 turns is for a new engine. Try 3/4 turns. If you get it too tight, your performance will suck.

Too loose and you'll hear rattle but it will run fine.

Arn

quote Originally posted by 87antuzzi: I ... tightened the rocker nut until the pushrod got hard to spin.

That is far too tight! You have gone way past the zero-lash point. Burned valves are the most likely result if you leave it that way. Others have already posted the right way to do it, so I won't repeat what they said.

quote Originally posted by Arns85GT: The 1.5 turns is for a new engine.

No!!! If the zero-lash point is determined accurately, 1.5 turns is correct for any stock Fiero V6. The whole purpose of the exercise is to set the static position of the valve gear to the center of the range of adjustment provided by the hydraulic lifter. That ideal center point (inside the lifter) does not change as the engine ages.

[This message has been edited by Marvin McInnis (edited 05-08-2010).]

You turn 1.5 turns from the "zero lash" point. Any valvetrain wear on an older engine would be compensated for when initially finding the "zero lash" point.

Don't worry about the feeler gauge, that's only relevant for engines without hydraulic lash adjusters.

With hydraulic lifters, you're not actually setting a certain amount of lash - see Marvin's explanation above.

[This message has been edited by pmbrunelle (edited 05-08-2010).]

Ok. now this is confusing. I have the rods at zero lash. No play up and down and they spin freely. I do a 360 tightened turned and the push rods then become hard to spin again.....So wtf!

Forget the hard to spin stuff.
Your zero lash is when you get no more up and down movement of the push rod by hand.
You can still spin a push rod in a lubricated engine a lot of times when proper lash is set, sometimes easy, other times hard.
Besides using the spin method, how are you making the determination on which valves to adjust and when to adjust them?

I just adjusted the valves on my 2.8 (120K miles) and found that 1.5 turns after zero lash was too tight. When I would run a compression test after 1.5 turns, compression would be low in that cylinder. I found 3/4 turns to works just fine.
Jim

quote Originally posted by 87antuzzi: Ok. now this is confusing. I have the rods at zero lash. No play up and down and they spin freely. I do a 360 tightened turned and the push rods then become hard to spin again.....So wtf!

They're only supposed to be easy to spin at zero lash.

Once you start tightening 1.5 turns, they will become hard to spin again. It's supposed to do that - you're now compressing the lifter's internal spring.

[This message has been edited by pmbrunelle (edited 05-08-2010).]

You need to start AGAIN ! put the engine at TDC firing #1, you can then tighten ONLY 6 valves, Exhaust 1,2,3. Intake-1,5,6. THEN turn the enine 360 degrees to tdc #6 . Adjust Exhaust 4,5,6, , Intake-2,3,4,. you can do the adjust by spinning the pushrod while tightening the adjuster NUT untill there is No "Up & Down" movement while tightening the nut (NOT untill it stops spinning), Then 1 1/2 turns. You can ONLY do 6 valves at a time!, then turn 360 degrees & do the other 6.

Not to be rude, but there are many threads regarding setting valve lash. Here's an example: https://www.fiero.nl/forum/Forum2/HTML/107679.html

quote Originally posted by Blacktree: Not to be rude, but there are many threads regarding setting valve lash. Here's an example: https://www.fiero.nl/forum/Forum2/HTML/107679.html

I searched and found a couple threads. I just wanted to clarify all the info in the said thread.

I don't use the spin method. I use the back and forth method. I go up and down until the slop disappears and then back and forth until it just starts to catch a bit. That is closer to 0 lash as far as logic would dictate. As for the 1.5 turns, it was definitely too tight on my engine.

You have wear on the hydraulic lifter surfaces and cam surface. If the lifter is naturally compressing very slightly at rest compared to new, you don't want to flex it further. That is the reason for the 3/4 turn.

I currently have ARP conversion studs and they have SBC type threads. That uses 1/4 turn past 0 lash if you go to ARP

Arn

On the original Service Manual, you do have lash specification for exhaust and intake valve (I don't have it with me here).
The reason for different value (for any car in the world) is because due to the exhaust gas temperature, valve dilatation is bigger than intake. So you need a bigger lash.
You do it a thikness gauge to tune them perfectly

------------------
Bernard
Fiero V6 GT 1987 (Manual)

quote Originally posted by BL3200: On the original Service Manual, you do have lash specification for exhaust and intake valve (I don't have it with me here). The reason for different value (for any car in the world) is because due to the exhaust gas temperature, valve dilatation is bigger than intake. So you need a bigger lash. You do it a thikness gauge to tune them perfectly

That's true but for solid lifter engines, not hydraulic lifter Fieros