well i had my motor runnin for 20 mins for the first time. i hear a bunch of noise. i pull 1 valve cover of to tightin all the loose rockers that made noise. then i turn it off. take the other valve cover of and notice 1 missin pushrod!. i pushed the car back in my garage, take of the intake. then i c a pushrod layin on the block all bent up!.so i get another pushrod from my other motor. put it back together. tighten the rockers till they are very litle bit loose. but after 2-5 mins goes by every other rocker arm gets loose. y is that? its starting to **** me of to a point im bout to give up and blow the car up. so if any 1 knows why my rockers keep coming loose please post back
thanx

 

Tell us a little about this motor...

Has the motor ever run before with this valve train?

What heads? Valve springs? Rockers? Cam?

Sounds to me like there's a major interference issue somewhere.

 

Doesnt sound like you are following the correct procedure for adjusting your rockers. I recommend getting yourself a Chilton manual for your car and follow the instructions on rocker arm adjustment.

 

if there aftermarket are you tighting the locker nut on top of them? other than that it really does not sound like you are even installing them right like Desert86Roc said

 

well many things come to mind:

coil bind causing the studs to pull out.
old wore out stock rocker crimp nuts. (if using stock)
not tightening the inner nut on posi locks ( if using them)

 

ok here are the specs

350 with 3k miles
pulled motor out and put in
new S\R torqer heads. 2.02\1.60 vavles. .560 max lift springs
515\515 lift with 300\300 dur. hydrolic lunati braket master ll cam
matched lifters.
1.6 roller tip rockers (from crane)
victor jr intake. and 650 DP carb.
all top end has 20 mins of run time (cam,heads,lifters,rockers,intake,carb)
the way i tightened up the rockers was with the motor onthe stand, which didnt work i guess. but i got em tight to a point we theres very little play and u can turn the pushrod a lil. so now after i turn the motor over *note its not starting yet*1 or 2 rockers get a lil loose ,sometimes 1 rocker gets loose. the bolts are brand spankin new that came with the rockers ,same with the specail washers that come with em, im thinkin if i have to use my old nuts and washers or what. im geting to a point to blow the whole car up. i have another timing problem possibly. i give it gas to start and grey smoke poofs out the carb, lol its pretty funny,but pisses me of. could my dis. be in backwards? what could be rong?it sounds like it wants to start but sounds like its backfiring or missing, the wires are in correct order.it ran fine before i took the top end of to change the pushrod.after i put it backtogether it started up once but sounded like somethin wasnt rite. and now it completely dont want to start. i dont have a clue no more. i apreiciate the help.

 

Nice head/cam/intake combination. Too bad the carb is so small. An 850 would go real good with that combination. How much compression is the engine?

Torquer heads I'm assuming have screw-in studs. If not the those springs could be pulling the pressed in studs out.

When adjusting hydraulic lifters you only need to adjust them once and the lifters must have oil in them before being adjusted.

Move the piston to TDC so that both valves are closed. Adjust the rocker so that the free play is gone from the pushrod then tighten the rocker nut 1/2 turn more. That sets very close to a .030" preload on the hydraulic lifter. Go around and do each cylinder seperately if you have to.

I don't like the "spin the pushrod" method of finding zero lash. Since the hydraulic lifter has some torerance either way I just tighten the rocker until the pushrod isn't sloppy any more. That's as close to zero lash as you're going to get. Then set the .030" preload which is very close to 1/2 turn on the rocker nut. If you're real picky, you can use a dial gauge.

If your rockers still become loose after that then you probably have a lifter problem or a valve clearance problem. Check all your pushrods to make sure none are bent. That .515 lift is for 1.5 rockers and using 1.6 rockers now makes .549 lift. Maybe the valves are hitting the pistons, bending the pushrods and making the rockers loose.

From the sound of how you're described it running, that would be my guess as to what's wrong.

You're also going to need good hardened pushrods for those valve springs. Stock pushrods won't last long under those spring pressures.

 

My Cymer 82-84 manual says:

Turn crank to compression stroke for #1 cyl and align timing mark to "0" degs.
Adj 1,3,4,and 8 exh and 1,2,5,and 7 intake valves.

Rotate crank exactly 1 turn.
Adj 2,5,6,and 7 exh and 3,4,6,and 8 intake valves.

To adj:
Loosen till lash is felt in pushrod.
Tighten till lash is removed and pushrod cannot be turned.
Continue tightening 1 full turn.

This info may not be completely accurate for your application, but does show that hydraulic lifters need to have their plungers centered
(i.e. preloaded) with eng cam and crank at specific positions.

The guy who rebuilt my top end a few years ago said after running a few hours, remove valve covers, idle eng (what a mess!) loosen rocker till tapping can be heard, tighten till tapping sound stops, then continue turning 5/8 of a turn.
When tightening with eng running; tighten VERY VERY slowly. Give the lifter a chance to bled off some oil. If you turn it fast, your piston may kiss that valve!
As you can see, there's some disagreement on how much to continue turning after slop has been taken out.
Probably should check with your lifter manufactor on that spec.

A manual for your car/eng certianly wouldn't hurt either.