i have roller prw 1.6 rockers with studs and hardened pushrods, its an olds 350 1970, the way he adjusted the rockers was while the motor was running he backed off the bolt on the stud till the rocker chattered then turned it till it stopped and did a qtr turn more and set the the set screw in the middle, ok so all was well from what i thought, i have a flat tapped cam and hydrolic lifters, mind you, so i assumed after break in u would have to adjust them one last time and be done with it, i looked on youtube and found someont explaneing how to do it so i figured id try, the first thing i noticed was when checked some of the pushrods there was some extremely loose before i released the set screw and the rocker screw, so i went thru the valvetrain doing them one by one and i noticed that on some when i would try to set the lash i was bottoming out on the stud?! i dont understand why, i ordered them from the guy who did the engine work, ( boring, port and polish), so i made another assumption and just went thru them all some was bottomed out and some werent, well when i dried to start the engine it turned over but wouldnt run, i didnt crank for more then 3 sec, i then took it apart and released all the pressure from the rockers and started to make sure i didnt bend a valve so it ran so i think im good on that part, but what could be my problem? lifters not holding psi?wrong studs, please help someone
need help BADD!!! adjusting roller rockers
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okay reason the pushrod felt loose is because the lifter bleed down. when they have oil pressure the get tighter. so thats why they feel loose. this is why some people adjust them while the motor is running. me i adjust them with the engine off. i use the twist of the pushrod method. and when u tightened them all down all the way u opened up the valves so that is why the engine wouldnt start. i made this mistake when i was first learning and bent a few pushrods. i would remove the rr and pull the pushrods just to make sure they are all nice and straight. one i know they are good install everything again. but just tighten the rr by hand. here use these instructions to adjust them. this is how i learned after messing up new set of comp cam pushrods. http://www.compcams.com/v002/Instructions/Files/151.pdf
When you adjust them, remember to have it as hot as you can. When the engine heats up (especially if aluminum heads) the rocker clearance will tighten even more and more. So if you adjust everything cold, it will be too tight after it warms up.
Another thing I always remembered was looser is better than tighter. Looser is more power, tighter is just less noise. Sometimes you end up going way too tight on a few of them just to get that last little bit of ticking noise to go away, that's not good. The lifter is always trying to pump up and hold as much oil as possible and automatically bleeds down supposedly the right amount. Knowing that, I still try to set them as loose as possible to lessen the wear and rotating drag on the cam. I normally adjusted each till the noise was mostly gone, then move on to the rest of them. I'd run through the whole valve train a few times until I was sure none were too tight, and none were too loud.
Another thing I always remembered was looser is better than tighter. Looser is more power, tighter is just less noise. Sometimes you end up going way too tight on a few of them just to get that last little bit of ticking noise to go away, that's not good. The lifter is always trying to pump up and hold as much oil as possible and automatically bleeds down supposedly the right amount. Knowing that, I still try to set them as loose as possible to lessen the wear and rotating drag on the cam. I normally adjusted each till the noise was mostly gone, then move on to the rest of them. I'd run through the whole valve train a few times until I was sure none were too tight, and none were too loud.
I always spin the pushrod with 2 fingers, and tighten the nut until I start feeling drag on the rod. I loosen the nut very slowly until I can spin the rod freely, but don't have any play, then I do ¼ turn. I'm not sure if the nuts for the rockers are too long for the studs or not, you mentioned them bottoming out. About 1/3 down this page you'll find the order to set them.
http://www.centuryperformance.com/adjus ... g-149.html
He said this is a hydraulic cam, not solid.
http://www.centuryperformance.com/adjus ... g-149.html
He said this is a hydraulic cam, not solid.
Just curious. Aren't Oldsmobile rocker arms adjusted differently than a Chevy small block? Perhaps with the roller rockers it's adjusted like a SBC. I've always heard that Olds rockers do not have a definitive adjustment. That the rockers are torqued down to a given ft. lb increment.
Please enlighten me.
Please enlighten me.
Crap.... I totally missed the Olds part :lol: I do know at least some of them are somewhat of a net-lash type setup, but if they're aftermarket they very well could be adjustable.
http://www.summitracing.com/parts/CSP-S5003/
http://www.summitracing.com/parts/CSP-S5003/
i called mondello racing and they told me i should have used an 8.5 -8.6 legnth pushrod, i had 8.2/5! just with knowing this should i assume my cam is gone?
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