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Hello all!! The question of the day well actually 2 questions. #1 does anyone know the torque specs and pattern on the head gasket for a 98 lumina 3.1 motor. also when putting the push rods and valves back in is there a pattern or order i need to follow? do they need to be torqued?
thank you in advance
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Head gasket
1st step 44ft/lbs
2nd step +95 degreespush rod and rocker
The correct torque for the rocker arm bolt is 14 N.m (124 lb in) plus 30 degrees.
Install the intake valve pushrods measure 144.18 mm (5.68 inch) long.
Install the exhaust valve pushrods measure 152.51 mm (6.0 inch) long.I set them all in place first starting from the center and work my way the extremities.
The order doesn’t really matter as long as you are not going from front to back as you put lot of stress on one hand and nothing on the other.
As long as you don’t mix the pushrod position. You want to screw the rocker arm nut all the way and use the torque I wrote down previously and you are done.
Usually when you install a cam in a hot rod… you want to make sure you are on the base circle of the cam… then you remove the slack until there is no play and add 1/2 turn and such…
It’s not the case on that one. But take in consideration that GM did the math to bring have the proper preload on the lifter.
No valve adjustment needed but be sure you get the intake and exhaust pushrods in the correct location. Very Important.
thanks you everyone your your info and advice. i have a new question. while i was at work my buddy (which is much older than me) put the push rods and rocker arms on and also the exhaust manifold. when he did this he snapped 3 bolds in the head for the exhaust manifold (which got me very mad). I wanted to take back apart and go to the machine shop but he said since the heads were put on and torqued down i would have to buy new ones again. so we finished putting it together. now it taps bad when its running and stalls everytime you stop. Im guessing he mixed up the rocker arms or the push rods or maybe both. thats the problem when people touch things when your not there. sorry if i seem angry but i thought by bring him to help it would go faster and better even more so because of his age. boy did i learn a lesson. Ill stick with the books and eric the car guy forum. (you guys never steer me wrong) But any advice would be most appreciated. Thank you in advance. John
Being angry/upset is understandable…many of us have been there either because of friends or ourselves (or in auto shop owners case people getting in over their head). If you were to properly fix your heads, then yes you’d need to replace your gaskets.
Mixing up the rocker arms and pushrods shouldn’t really cause it to stall. It could cause it to run rough. Mostly, it will just wear out your camshaft much faster than it should. Also, if some debris fell into the lifters, this could cause tapping. There’s a lot of reasons an engine could be “tapping.” To determine which, you should use your stethoscope and try to diagnose where and be specific on the sound. Also, does the rate of tapping fluctuate with your RPMs.
For the stalling and running bad, first check for vacuum hoses that are not connected or cracked. Diagnose where/what your sounds are and let us know so we can better help.
This might help for the pattern. Looks like someone already gave you the specs.
That said, I agree that mixing up the rockers and push rods would likely not cause the problems you’re having. For that I would look for vacuum leaks. I’d also go over your work to make sure everything was plugged in correctly. Lastly, make sure you bleed the cooling system. If not, problems can result. More info here.
http://www.ericthecarguy.com/faq/solving-automotive-performance-issues
http://www.ericthecarguy.com/faq/what-to-do-when-your-engine-overheats
Good luck and keep us posted.
i will keep you guys posted i took a break from that car sometimes thats the best thing. i will be back at it tomorrow let you guys kmow what i find.
ok guys i got some time to get back to my project lol, i started it up and took the oil cap off and looked inside and seen one rocker arm was moving while the other was not. could it be they are too tight or they are in the wrong order. the hard part for me is not being the one that did it so i dont know if the torque is right. i was wondering if i took the valve cover off and and seen nothing wrong would it be wrong to start the engine with the valve cover off and loosen the rocker arm til they move? or is that a no no. i was told by a older friend that helped with this project that is how they used to do it years ago but i am begaining to doubt his judgement lol guess thats why im here. thank you for all your help!!
You should be able to run the engine for a few minutes with the valve cover removed. Oil may spray out however but don’t be alarmed. If a rocker arm is not moving either the exhaust pushrod is installed on an intake valve or has jumped out of the lifter or the camshaft is worn out.
ok i pulled the valve cover off today. all the rocker arms were moving but one and only 3 of the 6 are shooting oil. any ideas?
only 3 were getting oil. so your saying its normal for the one not to move. i would think that it not moving would mean the valve is not opening and closing. am i wrong?
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