I was just checking out the '60 Pontiac 389 my fiance gave me, it was rebuilt when she bought it. When i pulled the VCs to check out the valve train, i noticed some of the rocker arms were loose. when i tried to tighten one the nut will go all the way down past the threaded area and never snug the arm down and it still just flops there. as far as i know the motor was rebuilt stock, and the rockers and studs should be correct. i will post pics soon
well it was rebuilt and never fired by my understanding.. not to say thats not out of the realm of possibility. motor is set to top dead center, no oil in it, no trans, clean as a whistle, and fresh paint.. i will pull the valley pan and have a look.
yea, im thinkin ajmopar might be right, but not sure, pulled the valley pan and found one area of the cam thats lost its smooth curve opposite of the lobe.
Wind it up a little, maybe. Often the rocker studs will pull up out of the head. Loosen the rocker and give the stud a wack. See if that tightens things up some. If it does you need (1) oversize studs. Hard to find and not that great. (2) threaded screw in studs. Great stuff but expensive and labor intensive or (3) pinned studs. Drill the boss and into the stud with a 1/16 drill bit after seating the stud and drive a pin into it to lock it in place. this was Pontiacs repair. It can be done with the heads on. But it's a pain and you may want to buy a bunch if 1/16 drill bits.
If the engine appears to be stock it should then have a hydraulic camshaft. Chances are the lifters were not soaked prior to installation and the engine was also not "primed" . If this is the case your lifters need to be pumped up. Then, you can properly adjust your valves .
sounds like its an issue over my head and i should let someone who knows what they're dealing with to do it. since it seems like the cam needs to be reground, whats a good grind or a good kit to replace it with? (stay with the hydrolic or go with a roller or solid) i saw isky has some awesome kits for the early pontiacs. i think Engle still does to but i haven't been able to get their page to open for quite some time.
"No oil in it" I bet you Axle's suggestion is right on the money. Follow up on that before you go off on a tangent looking for a cam and all the ***ociated expenses. Priming the engine with oil and a 1/2-inch drill just might be the exact fix.
Ya let someone who knows vintage Pontiacs have a peek first... Hydraulic lifters need pressure to pump up- that's probably all it is anyway. (Time to buy a book and do some homework son!)
If you prime the oil pump from the distributor remember. Counter clockwise distributor rotation is just one of the many improvements Pontiac made when designing their version of the pushrod V-8 engine. Moving the distributor to the other side of the cam gear not only gave a Pontiac distributor a counter clockwise rotation but it also has the added benefit of the thrust trying to pull the dist back into the motor as opposed to the thrust trying to push the dist out of the motor like a chevy. __________________
Yep.....I love the old Pontiacs, here's what you need to check.....first of all pull both valvecovers, the valley pan. 1.get a machinists scale.....measure from the tip of the stud to the boss or guideplate....measure 4 or 5....if they're all the same or really close....move on.... 2.Look at your base circle and lobe on all your cylinders....make note of the ones that are wore. 3. the ones that are wore, pull those lifters and marl them so they'll go back into the same holes. 4. Check your rocker arms....look to make sure the ball sockets aren't sunk into the rocker arms.....and also that the ball has no undue wear on it. 5. Where the pushror fits into the rockers....make sure that the pushrod isn't about to poke thru the rocker arm.... If everything shows good. prime the engine to build up oil pressure, and let the pressure run for about 2 or 3 minutes to prime all your lifters....look where the missing lifters were removed....you should have oil there......soak them in clean oil and pump them up and install them.....replace any worn parts....adjust everything and start runnin' her.........
If you do not know Pontiac rockers are not adjusted like a Chevy. They have a shoulder or a bottle neck if you want 7/16 shaft 3/8 thread to where the nut bottoms out and is torqued to 19 ft lbs if I remember correctly.
when doing a search to figure out how to pump the lifters up i found this on the crane cams web site.. "Many people mistakenly believe that hydraulic lifters must be soaked in oil overnight and be hand pumped up with a pushrod before installing into a new engine, however this is not necessary. In fact, this could cause the lifter to act as a solid and prevent obtaining proper preload. What is very necessary is the priming of the entire engine's oil system before starting up a new engine for the first time. This is done by turning the oil pump with a drill motor to force oil throughout the entire engine." this must be correct right?
'60 is a ***** to change cams in because the valvetrain is two-year-only and changing the cam can screw up the rest of the geometry. Or so I was told; either way never got mine finished because of that issue. I was going to suggest a stud had worked loose, but you could swap lifters temporarily and see if that makes a difference too.
i dont think its the stud. i believe its that the lifters were never set up and the engine not being primed like Axle and other have stated, the motor was ***embled then never had oil added or anything. i think the only time it was ever turned over is when i turned it over to make sure it wasnt seized. unfortunately it does not have a dizzy or starter at this time so some of what i think you guys are suggesting may not be able for me to do yet.
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